PREP 2019 Flashcards
When does ALCAPA typically present?
Between 1-4 months of age
Why are ALCAPA patients asymptomatic in early infancy?
Persistent elevation of the PA pressures promotes antegrade flow through the anomalous coronary artery
*Even though it is desaturated, this is usually enough to give O2 to LV
What causes symptoms to develop in ALCAPA?
- PVR falls, so the CPP also decreases
- This causes flow reversal in the coronary and leads to myocardial ischemia to the LV
- Ischemia leads to decreased LV function, papillary muscle dysfunction, MR and MI
How do infants with ALCAPA present?
Non-specific signs: Dyspnea, feeding intolerance, weight loss, irritability (especially with feeding… caused by angina due to increased O2 demand with feeds)
What is seen on CXR for ALCAPA?
Cardiomegaly from dilated LV
What is seen on the ECG in ALCAPA?
- Deep Q waves in I and aVL
- Repolarization abnormalities in precordial leads (V4-V6)
*Abnormalities in the ST segments aren’t consistently seen with this defect
Why is the diagnosis of ALCAPA from echo challenging?
- 2D images, LCA can appear to arise from aorta
- Need color Doppler to document origin of LCA from PA as well as flow reversal during diastole in the left coronary system
Besides the abnormal coronary origin, what else is often seen on echo in ALCAPA patients?
- Mod-severe MR with “chalk-stick” appearance to the papillary muscles
- Dilated LV with poor function
What causes MR in ALCAPA?
Ischemic injury to the LV papillary muscles
If ALCAPA can’t be diagnosed via echo, what are other options?
- CTA (cardiac gating to synchronize images to HR)
- Aortic root angiography in cath lab (gold standard for evaluating coronary origins)
*MRI can be used, but CTA is better in this age group
What is the differential diagnosis for ALCAPA?
DCM and viral myocarditis
What is the management for ALCAPA?
Surgery
*Supportive measures (inotropes, ventilation, etc) while awaiting definitive surgical repair
What medications are often required after ALCAPA repair?
PO heart failure therapy (to treat ongoing heart failure from ventricular dysfunction)
How long does the ventricular function take to normalize in patients after surgical repair of ALCAPA?
Several months
A loud crescendo-decrescendo systolic murmur that radiates to the carotid arteries, single S2 and delayed/diminished peripheral pulses suggest what?
Severe AS
In an asymptomatic patient, a cath peak to peak gradient above what results in the recommendation for aortic valvuloplasty?
50mmHg
In a symptomatic patient (angina, syncope, ischemic ECG changes at res or exercise), a cath peak to peak gradient above what results in the recommendation for aortic valvuloplasty?
40mmHg
What echo gradient better approximates a cath peak to peak gradient?
Mean Dopper-derived gradients (or peak gradients corrected for pressure recovery)
*vs. Peak instantaneous gradient
The 2014 AHA/ACC guidelines define severe AS as a Doppler velocity > what?
4M/sec
The 2014 AHA/ACC guidelines define severe AS a mean gradient > what?
40mmHg
What is the recommended management for severe congenital AS in infants, children and adolescents?
Balloon valvuloplasty
When might surgical valvotomy/repair be recommended for AS?
If there is significant AI with the severe AS
Why does medical management not help valvar AS?
It is a fixed obstruction
True or False: B-blockers are beneficial in valvar AS?
False- They are helpful with alleviated dynamic obstruction in HOCM, but not valvar AS
What is recommended to help with chronotropy in patients with moderate AS who want to participate in recreational activity?
Improved hydration
True or False: Exercise testing in asymptomatic AS is relative safe
True
True or False: Patients with symptoms provoked only by exercise testing are considered asymptomatic
False- Symptomatic even if the clinical history is equivocal
Why is exercise testing not recommended in symptomatic patients with severe AS?
Can precipitate syncope, v-tach and sudden death
What is one of the primary causes of hemoptysis in Fontan patients?
Persistant or new AP collaterals
What is considered a significant risk factor for AP collaterals in a Fontan patient?
Cyanosis
*The APCs can then lead to hemoptysis
True or False: Fontan completion if relatively protective against the formation of AP collaterals?
True- Patients left at Glenn are more cyanotic which leads to more APCs v. those with Fontan completion
Why do APCs tend to improve following Fontan completion?
Improved saturations
What causes persistent AP collaterals in Fontan patients?
- Mild Hypoxemia
- Abnormal/non-pulsatile flow to the PAs
True or False: Physical activity and exertion are risk factors for hemoptysis?
False- Hemoptysis tends to occur sporadically
What is the first line treatment for hemoptysis due to AP collaterals?
Cath with selective APC embolization
What is an option for recurrent hemoptysis due to AP collaterals?
Pulmonary lovectomy
What would be a reason to avoid an ACEi for an adolescent with HTN?
If they are sexually active and not using protection
True or False: B-blockers aren’t recommended as initial treatment for hypertension in children?
True- Due to potential adverse effect profile and lack of data to support long-term benefits in children
What would be the choice of anti-hypertensive agent for an adolescent who is sexually active?
CCB like amlodipine (avoid ACEi due to teratogenicity)
What are the 2 major classes of CCB?
- Dihydropyridine (smooth muscle selective)
- Nondihydropyridine (relative myocardium selective)
How do dihydropyridine CCB work?
-Block L-type Ca channels on vascular smooth muscle causing reduction in vascular resistance and arterial pressure
What type of drugs are amlodipine, felodipine, isradipine, nicardipine, nifedipine, nimodipine and nitrendipine?
Dihydropyridine CCB
What type of drugs are verapamil and diltiazem?
Nondihydropyridine CCB
What are the nondihydropyridine CCB (verapamil and diltiazem) typically used for?
Anti-arrhythmics
What are some side effects associated with CCB?
Flushing Headache Hypotension Edema Reflex hypertension
What are some side effects specific to the cardiac-specific nondihydropyridine CCB?
Negative effects on the SA node and AV node
Shouldn’t be used in patients with bradycardia or conduction abnormalities
What drug class should be considered as treatment for HTN in patients with contraindications to ACEi?
Dihydropyridine CCB
What are the 2 main types of CCB and what is their use?
- Dihyrdopyridine: HTN
2. Non-dihydropyridine: Anti-arrhythmic
Kartagener syndrome is a subgroup of what?
Primary ciliary dyskinesia (PCD)
Situs inversus totalis
Chronic sinusitis
Bronchiectasis
Kartagener
Primary ciliary dyskinesia is caused by a defect in what?
Proteins in cilia
True or False: There is considerable variation in the clinical presentation of primary ciliary dyskinesa?
True
When do most patients with primary ciliary dyskinesia present?
Childhood (but some don’t present until adulthood)
How is primary ciliary dyskinesia inerited?
AR
*Multiple genetic variants have been indentified
What feature must be present for the diagnosis of Kartagener?
Situs inversus
Situs inversus if found in what % of patients with primary ciliary dyskinesia?
50%
What syndrome can be seen in association with primary ciliary dyskinesia?
Heterotaxy
True or False: It is common for patients with situs inversus totalis and primary ciliary dyskinesia to have CHD?
False
True or False: It is common patients with heterotaxy and primary ciliary dyskinesia to have CHD?
True
True or False: No single test has been established as the definitive standard for the diagnosis of primary ciliary dyskinesia?
True
What are options in the workup of primary ciliary dyskinesia?
- Respiratory epithelial biopsy with electron microscopy
- Measurement of nasal NO
- High-speed videomicroscopy analysis of cilia
- Cell culture of ciliated cells
- Genetic testing
*Current recommendations don’t rely on 1 test, panel is required to confirm diagnosis
What is the most common cause of acquired CAD in children?
Kawaksaki
What is included in the recommendations for routine surveillance in Kawasaki patients?
- Echo in those with persistent coronary artery abnormalities
- Exercise or pharmacologic stress imaging with persistent coronary artery aneurysms
What are options for exercise or pharmacologic stress imaing in kids?
- Stress echo
- Stress with MR perfusion imaging
- Stress with nuclear medicine perfusion imaging
How is conventional stress testing in children performed?
Graded exercise on a treadmill or cycle ergometer (often combined with metabolic measurements of CO)
What is done to assess cardiac structural and/or functional response to exercise?
- Exercise echo
- CMR
What is done for exercise stress imaging in a young patient or someone who can’t exercise?
Pharmacologic stress test
How does a pharmacologic nuclear stress test work?
- IV injection of nuclear isotope and pharmacologic agent (adenosine, dipyridamole, dobutamine) to stress the heart in lieu of exercise
- Then obtain nuclear images (high radiation dose)
*Can use echo or CMR pharmacologic stress imaging as alternative to nuclear
What is a disadvantage of a pharmacologic nuclear stress test?
High radiation dose
List some potential indications for nuclear stress perfusion imaging in pediatrics
- History of Kawasaki disease
- Identification of transplant coronary artery vasculopathy
- Assessment of coronary artery insufficiency in d-TGA s/p ASO
- Assessment of coronary artery insufficiency following surgical coronary reimplantation for congenital anomalous origin of the coronary artery
What is indicated for children with persistent coronary artery aneurysms s/p Kawasaki?
- Exercise stress imaging or
- Pharmacologic stress imaging (if can’t exercise)
Why is nuclear medicine stress testing limited in pediatric?
Significant radiation exposure
Tachycardia with RBBB pattern, LAD and relatively narrow QRS (120-140msec)?
Fascicular ventricular tachycardia
True or False: You can have VA dissociation in fascicular ventricular tachycardia?
True
True or False: Patients with fascicular ventricular tachycardia can develop subacute onset of heart failure?
True
What medication is most likely to terminate fascicular ventricular tachycardia?
Verapamil
What are some other names for fascicular ventricular tachycardia?
Idiopathic left ventricular tachycardia
Verapamil sensitive ventricular tachycardia
Verapamil-sensitive left ventricular septal ventricular tachycardia
Belhassen tachycardia
*Also RBBB ventricular tachycardia or Purkinje-related ventricular tachycardia (less specific)
What is a reentrant tachycardia that involves the fascicles of the LBB?
Fascicular ventricular tachycardia
What age and what gender is fascicular ventricular tachycardia most common in?
Teenagers and young adults
Male
True or False: Fascicular ventricular tachycardia is monomorphic and generally well tolerated?
True
*Can be paroxysmal or incessant, can present with tachycardia induced cardiomyopathy
Describe the circuit in fascicular ventricular tachycardia
- Orthodromic limb of slowly conducting myocardium with verapamil sensitivity
- Retrograde limb involving the Purkinje network
Describe the appearance of left posterior fascicular ventricular tachycardia
RBBB pattern
LAD
(90% cases)
Describe the appearance of left anterior fascicular ventricular tachycardia
RBBB
RAD
(10% cases)
Describe the appearance of high fascicular ventricular tachycardia
Narrow QRS
Normal axis
(<1% cases)
V-tach with RBBB and LAD pattern?
Left posterior fascicular ventricular tachycardia
True or False: In general, fascicular ventricular tachycardia doesn’t cause acute hemodynamic compromise unless cardiomyopathy is present
True
What is the short term management of fascicular ventricular tachycardia?
IV verapamil- Slows and terminates rhythm
What do you need to be cautious about before giving IV verapamil in fascicular ventricular tachycardia?
That there isn’t significant myocardial dysfunction
Besides verapamil, will any other medications terminate fascicular ventricular tachycardia?
- Adenosine and B-blockers, but less likely to work
- Digoxin, No
- Class I (procainamide) or class III (amiodarone) medications may work, but aren’t usually needed
What should be done for fascicular ventricular tachycardia associated with hemodynamic compromise or is refractory to other treatment?
DC Cardioversion
What is the long-term management of fascicular ventricular tachycardia?
-PO verapamil or -Class I or III agents (Flecainide, sotalol, amiodarone) or -RF ablation (typically curative)
Ventricular tachycardia with a RBBB pattern, LAD and relatively narrow QRS (120-140msec) should raise suspicion for what?
Fascicular ventricular tachycardia (especially in a structurally normal heart)
Short term termination and long-term suppression of fascicular ventricular tachycardia are achieved with what?
Verapamil (IV for termination, PO for long-term)
What is the most common cause of sudden cardiac arrest in children in the US?
HCM
*Accounts for over 1/3 of cases
What is the second most common cause of sudden cardiac arrest in children in the US?
Anomalous coronaries
Which is more concerning, an anomalous RCA from the left sinus or anomalous LCA from the right sinus?
Anomalous left
What is a concern when there is a severely dilated sinus of Valsalva and ascending aorta (>5cm in adults)?
Dissection leading to aortic rupture
How would an aortic dissection present?
Chest pain, collapse, hemopericardium, hemothorax
True or False: Although DCM can cause ventricular arrhythmias, it is an uncommon cause of SCA?
True
What is on the differential diagnosis for sudden cardiac arrest?
HCM
Coronary anomalies
*Others: Other cardiomyopathies (DCM), myocarditis, ARVC, CAD, AS, commotio cordis, ion channelopathies (LQTS)
What is the most common gene mutation in patients with primary pulmonary HTN?
BMPR2 (bone morphogenetic protein receptor II)
- Mutations in 10-40% of cases of idiopathic pulmonary HTN
- Familial pulmonary HTN, frequency increases to 70%
How is idiopathic pulmonary hypertension diagnosed?
When the results of a diagnostic evaluation for known causes of pulmonary hypertension are negative
Childhood presentation of pulmonary HTN is commonly associated with what?
CHD
Lung disease
*Need to rule out rare causes like connective tissue disease, liver disease or thromboembolic disease
Mutations in ALK1 (activin-like kinase type 1) are associated with what?
Hereditary hemorrhagic telangiectasia: Telangiectasias, epistaxis, cyanosis
Mutations in GBA (B-glucocerebrosidase) are associated with what?
Gaucher disease: Lysosomal storage disease with AR inheritance
*May get pulmonary HTN if ILD is present
Variations in HLA-DRB1 have been associated with increased risk for developing what?
Autoimmune disorders: Addison disease, MS, RA, T1DM, Sarcoidosis
What is the primary pulmonary HTN gene?
BMPR2 (bone morphogenetic protein receptor II)
The hemodynamic effects of an ASD are determined by what?
- Size of defect
- Compliance of LV and RV
L-R shunting across an ASD cause dilation of what?
Right heart
High Qp:Qs and resultant right heart dilation due to ASD are typically seen in what patients?
Those with moderate-large defects that occur in patients with low PVR (results in highly compliant RV that favors L-R shunting)
What would you see clinically in someone with an ASD, pulmonary vascular disease, stiff RV or elevated RVSP?
Desaturation due to R-L shunting
Why would a patient with a non-compliant LV or LVOTO be more likely to have a hemodynamically significant shunt across an ASD?
Elevated LA pressure
*Similar in situations with LA volume overload, like a VSD or nonrestrictive ductal shunt
Why do ASDs allow smaller volume shunts than VSDs of the same size?
Because atria are low-pressure chambers
True or False: In patients with normal hemodynamics, there is only a small pressure gradient between the LA and RA?
True
- Compliances assumed to be fairly equivalent
- Why atrial compliance doesn’t influence hemodynamic effects of an ASD (as much as size of defect or ventricular compliance)
Isolated congenital MR is most often due to what?
Dysplastic MV
Perinatal cardiomyopathy
In children >1 year, what are some causes of mitral regurgitation?
- Acute rheumatic fever
- Myocarditis
- Endocarditis
- Cardiomyopathy
- Kawasaki disease
- Coronary artery anomalies
- Collagen vascular disease
- Trauma to valve or chordae
What are some hemodynamic sequelae of severe MR?
- LV dilation
- LA enlargement
- Elevated pulmonary venous pressures
- Pulmonary edema
- Pulmonary HTN
How do infants with severe MR present?
CHF- Increased work of breathing, poor weight gain, FTT
What causes the CHF symptoms in an infant with severe MR?
Pulmonary edema due to LA HTN and decreased CO
True or False: Ventricular function is usually preserved in the short/intermediate term in severe MR?
True
*Although patients may eventually develop ventricular dysfunction and pulmonary HTN
What is the initial treatment of congenital MR?
Medical management:
- Diuretics (Lasix): Treat pulmonary edema and decrease WOB
- Maximize calories
- ACEi: Not recommended in adults, but can be used in small children
When is surgery considered for congenital MR?
When maximal medical therapy has failed
Why is MV repair in congenital MR challenging?
- Often unsuccessful or creates MS
- Replacement is hard because smallest mechanical valve is 15mm and larger than average annulus in infants… often has to be placed in the supra-annular position in the LA
Patients with progressive CHD or end-stage cardiomyopathy secondary to congenital MR may require what?
Heart transplant
Mechanical circulatory support with VAD
What is often seen on CXR in a neonate with ToF absent PV?
Cardiomegaly
Air trapping
Dilated proximal branch PAs
What is seen on CT in a neonate with ToF absent PV?
- Markedly dilated proximal branch PAs distal to a “waist” representing the plane of the rudimentary PV leaflets
- Tracheal narrowing
- Compression of mainstem bronchi on side of arch (between dilated PA and descending Ao)
- Differential air trapping (due to bronchial compression)
ToF absent PV occurs in what % of ToF patients?
3-6%
The rudimentary PV tissue in ToF absent valve is associated with the prenatal development of what?
- Severe PI
- Marked dilation of the proximal branch PAs
- Mild-mod PS/obstruction
What form of CHD should you consider with absence of the ductus arteriosus?
ToF Absent PV
*Absence of ductus may contribute to the pathogenesis of the condition
ToF absent PV is association with what genetic condition in 20-25% of cases?
Chromosome 22 microdeletion
*Others as well… genetic testing should be done as part of perinatal testing in these patients
What is seen on fetal echo in ToF absent PV?
- Severe PI
- Marked PA dilation
- Typical overriding aorta/VSD
What can result in utero from the severe PI in ToF absent PV?
- Fetal CHF
- Hydrops fetalis
- Fetal demise
Besides a fetal echo, what other testing can be done to help risk stratify in ToF absent PV?
Fetal MRI
- Assess lung volumes
- Assess potential for perinatal pulmonary obstruction
What causes the severe respiratory distress that can be seen in ToF absent PV?
- Bronchial compression (from dilated/pulsatile branch PAs and right arch if present)
- R-L shunting through VSD due to presence of elevated pulmonary resistance
What can be done for a neonate with severe respiratory distress due to ToF absent PV?
- Ventilator with PPV
- Prone (decreases severity of bronchial compression/air trapping)
*Some may need ECMO or early surgery
True or False: Neonates with ToF absent PV may have hypoplasia of distal branch PAs beyond the regions of marked dilation?
True- Persistent desaturation due to inadequate PBF
True or False: Some neonates with ToF absent PV can have surgery at a time similar to classic ToF?
True- some have mild symptoms and don’t need significant cardiorespiratory support
What is the characteristic murmur in ToF absent PV?
Harsh to-fro murmur of PS/PI
True or False: PGE is indicated in ToF absent PV?
False- Typically no ductus, so PGE won’t work
What are important ventilator management strategies in ToF absent PV?
- Increased PPV
- Prone position (improves airway compression for dilated/pulsatile branch PAs)
When should children be started on medications for HTN?
- Remain hypertensive despite trial of lifestyle modifications
- Symptomatic HTN
- Stage 2 HTN w/o clearly modifiable factor (obesity)
- Any stage HTN with CKD or DM
What are the cutoffs for treatment of LDL after 6 months of lifestyle modifications are attempted?
- LDL >190
- LDL >160 + 1 (FHx stroke, MI, SCD, 1 high risk factor or 2 moderate risk factors)
- LDL >130 + 1 (2 high risk factors or 1 high risk factor +2 moderate risk factors)
What constitutes a + FHx in terms of dyslipidemia risk?
MI, angina, coronary artery bypass graft/stent/angioplasty, SCD in parent, grandparent, aunt or uncle (< 55 men and <65 in women)
What are the high-level risk factors in terms of dyslipidemia risk?
- HTN requiring drug therapy (BP >99th% + 5mmHg)
- Current cigarette smoker
- BMI at or >97%
- High risk conditions: DM1, DM2, chronic renal disease, ESRD, post-renal transplant, post orthotopic heart transplant, Kawasaki with current aneurysms
What are the moderate-level risk factors in terms of dyslipidemia risk?
- HTN not requiring drug therapy
- BMI at or >95%, but <97%
- HDL <40
- Moderate risk conditions: Kawasaki disease with regressed coronary aneurysms, chronic inflammatory disease (SLE, juvenile RA)
- HIV
- Nephrotic syndrome
True or False: History of cancer and chemotherapy may impact the assessment of lipids in children
True- Certain chemotherapeutic agents may be a secondary cause of elevated lipid levels
True or False: History of cancer and chemotherapy are considered independent risk factors which influence therapeutic decisions regarding HLD?
False
List potential side effects of ACEi
- Bradykinin-induced cough (10% of adults, less common in kids)
- Elevated K (especially when given with other drugs that raise K or with decreased GFR)
- Hypotension
- Neutropenia
- Angioedema
- Skin reactions
What would be a concern for use of an ACEi in someone with severe asthma?
Potential for bradykinin-induced cough to exacerbate bronchospasm and asthma symptoms
What are some specific side effects/problems with captorpil?
- Adverse effects to the immune system (subacute cutaneous lupus erythematosus, drug induced lupus)
- Captopril-associated neutropenia may not be reversible in patients with collagen vascular disorders
How does carvedilol work?
Non-selective B-blocker with a-blocking properties
True or False: Carvedilol use can affect pulmonary function tests
True
True or False: B-blockers like atenolol or propranolol have been associated with a 5-10% reduction in FEV1?
True, but patients with mild asthma may still tolerate a B-blocker
How do ARBs work?
Block formation of angiotensin II
True or False: ARBs can still cause cough and angioedema, just not as often as ACEi?
False- The bradykinin adverse effects of ACEi (cough, angioedema) don’t occur with ARBs
Lorsartan is often used in patients with HTN and what other issue?
LVH (LIFE, Losartan Intervention for Endpoint Reduction) study showed atenolol to be inferior to losartan in the treatment of HTN and LVH
ACEi and ARBs are contraindicated in what circumstances?
- Pregnancy
- Severe renal failure
- Hyperkalemia
- Renal artery stenosis
- Severe aortic stenosis
- Obstructive cardiomyopathy
Besides ARBs, what other drug category are often used with good results in adults with HTN and asthma?
CCB
What produces an ejection click?
Sudden augmented distension of the great vessel wall when a normal volume of blood is ejected under high velocity and pressure
What happens to the timing of a systolic ejection click with more severe stenosis?
It moves earlier in systole until it merges with S1
What 3 things can help to differentiate the degree of PS by auscultation?
Timing of the click
Description of S2
Duration of systolic murmur
What does inspiration do to P2 normally?
Delays it
What causes the normal delay in P2 with inspiration?
Increase in RV ejection time
Reduced impedance of pulmonary arterial vascular ved
Describe the timing of the murmur in mild PS
Short
Peaks at or before mid-systole
Ends well before the aortic closure sound
Describe the timing of the murmur in severe PS
Extends beyond the aortic closure sound (which may become inaudible)
Split S2 may not be appreciable
What degree of PS will have a prominent RV precordial impulse and thrill at the LUSB?
Severe
Why might a critical PS baby have a soft systolic murmur across the PV?
Low cardiac output
What would cause a holosystolic murmur at the LLSB in critical PS in a neonate?
TR
What causes cyanosis in critical PS?
R-L atrial shunting
What is a classic exam findings in a large secundum ASD or sinus venosus ASD?
Widely split S2 that doesn’t vary with respiration and has normal intensity of both aortic and pulmonary components
What causes a fixed split of S2 in ASD?
During expiration, the decrease in systemic venous return is matched by an increase in pulmonary venous return and L-R shunting across the ASD
What is different about S2 in a large ASD versus PS?
ASD: Wide and fixed splitting of S2
PS: Widely split S2 that maintains normal respiratory variation
What causes a low-frequency ejection murmur in an ASD at the LUSB?
Increased flow across the pulmonary valve
What is the vascular junction that bridges the umbilical venous circulation to the floor of the RA?
Ductus venosus
How do you find the ductus venosus on fetal echo?
Search for the region of color aliasing within the body of the liver
Describe normal flow in the ductus venosus
Entirely antegrade
Relative reduction in flow velocity during atrial contraction
What does the normal antegrade flow pattern with relative reduction in flow during atrial contraction in the ductus venosus reflect?
The pressure gradient between the ductus venosus and RA
Reduced flow velocity during atrial contraction in the ductus venosus reflects what?
Blunting of forward flow because of elevated RA pressure (absent A-wave)
*Reversal of flow with atrial contraction reflects more advanced disease
In a fetus with a structurally normal heart, what does an abnormal ductus venosus Doppler mean?
Elevated RA pressure and/or poor RV compliance… sign of fetal compromise
When would reversal of flow in the ductus venosus with atrial contraction be expected?
Fetuses with right-sided obstructive CHD
*If the RA pressure is elevated due to right heart inlet and/or outlet obstruction (tricuspid atresia, PA/IVS), flow reversal with atrial contraction is anticipated and “normal” for the underlying physiology
Would you expect flow reversal in the ductus venosus in PA-VSD?
No- Even though there is right-sided outlet obstruction, there is decompression of flow/pressure through the interventricular communication which minimizes the potential for flow reversal
What does flow reversal in the pulmonary veins suggest?
Left atrial hypertension
Fetuses with what type of CHD can have flow reversal in the pulmonary veins?
HLHS and restrictive atrial septum (due to LA hypertension)
*Degree of flow reversal varies based on the severity of the LA outlet obstruction
True or False: Isolated TAPVR is one of the most difficult lesions to detect prenatally
True
What are findings on fetal echo with isolated TAPVR?
- Lack of visible pulmonary venous connections back to LA
- Presence of descending venous channel in abdominal views (can get anomalous venous connection to ductus venosus, spectral Doppler would show significant turbulence)
What is DORV with subpulmonary VSD and CoA called?
Taussig-Bing anomaly
Transposition-type DORV
*20% of cases of DORV
What forms the base of the interventricular communication in DORV?
The limbs of the septomarginal trabeculation (or septal band)
What is the inner curvature of the heart (ventriculo-infundibular fold) between?
The AV and semilunar valves
The portion of the ventriculu-infundibular fold between the mitral and aortic valves exists as what in the normal heart v. DORV?
- Normal heart: Fibrous remnant
- DORV: Muscularized (suboartic conus)
What does the ventriculo-infundibular fold between the mitral and aortic valve form in DORV?
Part of the roof of the interventricular communication (often described as the subaortic conus
What is the outlet septum?
Muscular or fibrous portion of the ventricular septum that is between the 2 semi-lunar valves
What determines the relationship of the interventricular communication relative to the great vessels?
Rotation of the conus and thus great vessels determines the position of the outlet septum relative to the limbs of the septal band and thus relationship of interventricular communication relative to great vessels
In transposition type DORV, what is the position of the great arteries?
d-malposed
In transposition type DORV, the caudal or posterior-inferior limb of the septal band is attached to what?
Outlet septum
What can cause subaortic obstruction in transposition type DORV?
Malalignment of the outlet septum
Subaortic obstruction due to malalignment of the outlet septum in DORV is also associated with what?
Aortic arch obstruction
Which is more common, DORV with a subpulmonary VSD or DORV with a subaortic VSD (+/- PS)?
DORV with subaortic VSD
In DORV with a subaortic VSD, the outlet septum is attached to what?
Cranial limb of the septal band
In what type of DORV is the outlet septum not attached to either limb and usually a fibrous remnant rather than a muscularized portion of the septum?
DORV with doubly committed VSD
True or False: DORV with a uncommitted/remote VSD is uncommon?
True- The interventricular communication closes
What finding occurs in the setting of transposition physiology and aortic arch obstruction?
Reverse differential cyanosis
*Upper body has a lower SpO2 than lower body
Describe what causes reverse differential cyanosis as seen in DORV with subpulmonary VSD and CoA?
- Upper body gets deoxygenated blood that streams preferentially from RV to aorta
- Lower body receives oxygenated blood that streams preferentially from LV, through VSD to PA, then across PDA to desc AO
True or False: Reverse differential cyanosis confirms the presence of a PDA?
True- Close of the PDA in this physiology leads to decreased flow to the lower body and similar low SpO2 in the upper/lower body
Anterior deviation of the conal septum in DORV leads to what?
Subpulmonary stenosis
True or False: DORV with subpulmonary stenosis (anterior deviation of the conal septum) + aortic arch obstruction is unusual?
True
Patients with DORV and a subaortic VSD have physiology similar to what?
ToF- Often have pulmonary or subpulmonary stenosis
What type of patients can anomalies in pulmonary venous drainage be seen in association with DORV?
Heterotaxy
Reverse differential cyanosis with low SpO2 in the upper body and higher SpO2 in the lower body is seen in what physiology?
Transposition + Arch obstruction
DORV with a subpulmonary VSD is associated with what 2 things?
Transposition physiology + CoA
What is the incubation period for Lyme diease?
7-14 days
Describe Stage 1 of Lyme Disease?
Localized with classic bull’s-eye rash at site of tick attachment (painless and non-pruritic)
-Also have fever, malaise and regional lymphadenopathy
What is Stage 2 of Lyme disease?
Early disseminated disease- May manifest itself in any body system
What is a notable skin lesion seem in disseminated Lyme Disease?
Erythema migrans
What are some of the persistent symptoms seen in stage 3 Lyme disease?
Localized scleroderma Prolonged arthritis Gait ataxia Chronic encephalomyelitis Keratitis Fatigue
Do long-term antibiotics help with Stage 3 of Lyme disease?
No- these symptoms persist despite clearance of the infection and may last weeks-months
What are the cardiac manifestations of Lyme disease?
AV nodal block
Myopericarditis
Pancarditis
What % of patients with Lyme disease get cardiac manifestations?
4-10%
What is the most common type of heart block in Lyme disease?
1st degree (higher grades like 2nd/3rd degree only occur in 1% of patients)
How is early localized Lyme disease (without neurologic involvement or advanced AV nodal block) treated?
PO doxycycline, amoxicillin or cefuroxime for 10-21 days
What is the preferred parenteral antibiotic in Lyme disease?
Ceftriaxone
How is 1st degree AV block with a PR interval <300msec treated in Lyme disease?
Outpatient with PO antibiotics
What heart findings seen in Lyme disease should be monitored in the hospital and treated with parenteral antibiotics?
- 1st degree AV block with a PR interval of >300msec
- 2nd degree AV block
- 3rd degree AV block
True or False: Central or peripheral nervous system involvement with Lyme disease (except for cranial nerve palsy) should be treated with parenteral antibiotics?
True
What type of medication is tadalafil?
Phosphodiesterase-5 inhibitor
What are symptoms of idiopathic pulmonary HTN?
Dyspnea with exertion Intermittent cyanosis Syncope Chest pain Sudden death
What is the gold standard for the evaluation of pulmonary HTN?
Cath
What are the first-line treatments for an acute pulmonary hypertensive crisis?
O2
iNO
How does iNO work?
- Activates guanylyl cyclase
- Leads to production of itnracellular cGMP
- cGMP causes smooth muscle relaxation of pulmonary vasculature
If an acute pulmonary hypertensive crisis isn’t responding to O2 or iNO, what can be used next?
IV prostacyclins (epoprostenol or treprostinil)
How do the prostacyclins work (epoprostenol or treprostinil)?
- Prostaglandin analogs that cause direct vasodilation in all vascular beds (including pulmonary vasculature) via adenylate cyclase and cAMP
- Also potent endogenous inhibitors of platelet aggregation
What is the half life of epoprostenol?
6 minutes
What is the half life of treprostinil?
4 hours
What forms does treprostinil come in?
IV, subcutaneous, inhaled
What are the 4 classes of medications used in the management of chronic pulmonary HTN?
- Phosphodiesterase 5 inhibitors
- Endothelin receptor antagonists
- CCB
- Prostacyclin analogs
What are examples of phosphodiesterase-5 inhibitors?
Tadalafil and sildenafil
How do phosphodiesterase-5 inhibitors work (sildenafil and tadalafil?
- Inhibit phosphodiesterase-5
- cGMP levels increased in smooth muscle cells (prompts relaxation and vasodilation)
What is a common side effect of the phosphodiesterase-5 inhibitors?
Hypotension (effects not limited to just pulmonary vasculature)
What forms does sildenafil come in?
IV and PO
What forms does tadalafil come in?
PO only
What drugs are considered 1st line chronic treatments for idiopathic pulmonary HTN in children?
Phosphodiesterase-5 inhibitors
What are examples of endothelin receptor antagonists ?
Bosentan and ambrisentan
How do endothelin receptor antagonists work?
-Competitive antagonists of the endothelin receptors in the lung (ETa and Etb, slightly higher affinity for ETa)
- Stimulation of endothelin receptors increases levels of itnracellular inositol triphosphate (IP3) via Gq protein coupling
- Increased intracellular IP3 levels cause increased Ca release from sarcoplasmic reticulum and smooth muscle contraction or vasoconstriction
- Inhibiting the endothelin receptor prevents increased intracellular IP3 levels and promotes pulmonary vasodilation
When using a CCB for pulmonary hypertension, you should choose one from which family?
Benzothiazepine
Why should you pick a CCB from the benzothiazepine family when treating pulmonary HTN?
Relatively selective for vascular calcium channels
How do CCB work in pulmonary HTN?
-Prevent egress of Ca from SR and prevent vasoconstriction/promote vasodilation
True or False: Patients should be tested for vasoreactivity to CCB in the cath lab prior to initiation?
True
True or false: Coronary artery fistulas have equal distribution between male and female patients?
True
What are symptoms from a coronary artery fistula determined by?
Fistula location and size
What are possible problems associated with a coronary artery fistula?
- CHF due to L-R shunting (poor growth, tachypnea, tachycardia)
- Coronary steal and myocardial ischemia (irritability, fussiness, poor color with feeds)
- Endocarditis (SBE prophylaxis not indicated)
What is the most likely presenting symptoms for an infant with a large coronary artery fistula?
CHF
What is the most severe form of PAH?
Eisenmenger syndrome
What causes Eisenmenger syndrome?
- Intra or extracardiac shunt lesions with large/chronic L-R shunting that leads to progressive pulmonary vasculopathy
- High flow/pressure from shunts can induce pulmonary vascular endothelial damage which causes release of growth factors that induce smooth muscle hypertrophy and proliferation with neointima formation
How does endothelial dysfunction contribute to pulmonary HTN?
-Causes increased vascular ton from imbalance between vasoconstrictors and vadosilators
Endothelin-1 and thromboxane do what?
Vasoconstrict
NO and prostacyclin do what?
Vasodilate
The activation of the endothelin system contributes to what?
Pulmonary vasoconstriction and remodeling
True or False: Pulmonary arteriolar remodeling caused by medial hypertrophy can be reversible in the early stages?
True- becomes irreversible with disease progression
When what proportion of the pulmonary vascular bed is compromised does pulmonary hypertension ensue leading to R-L shunting and Eisenmenger syndrome?
2/3
True or False: Children with CHD who undergo early surgical repair typically do not develop advanced pulmonary vasculopathy?
True
Determining the feasibility of surgical repair of an adult patients with CHD with PAH requires what?
Cath: Need PVR, PVR:SVR and acute response to vasodilators
PVR > what is considered prohibitive for surgical repair of CHD?
> 8-10 WU/m2
A PVR:SVR > what is considered prohibitive for surgical repair of CHD?
> 0.5
What medication is considered a class IA therapy for symptomatic adults with Eisenmenger syndrome?
Bostenan
*Sildenafil and IV prostacyclin are being studied with encouraging results, but bosentan is recommended first line
What is often used as a 2nd line disease targeting therapy for symptomatic adults with Eisenmenger syndrome after bosentan?
Phosphodiesterase 5 inhibitors
Besides vasodilator therapy, what are 2 other important aspects of management for adults with Eisenmenger syndrome?
- Treatment of “relative anemia” (to hypoxia)
- Endocarditis prophylaxis
Which is preferred in patients with pulmonary hypertension secondary to CHD, PO or IV vasodilators?
PO- IV associated with frequent complications
PO CCB are used for what types of PAH?
Idiopathic or familial
Why are CCB not routinely used in Eisenmenger syndrome?
Negative inotropic effects
Systemic vasodilation
ToF accounts for what % of CHD cases?
10%
Complete AVC defects account for what % of CHD cases?
2-9%
What % of AVC defect patients have concurrent ToF physiology?
6-10%
The presence of coronary abnormalities in ToF is what?
5-7%
What coronary anomaly is seen in up to 4% of ToF patients?
LAD or and accessory LAD from RCA
How does a coronary branch crossing the RVOT alter the surgical approach in ToF?
With a crossing coronary, would pursue an RV-PA conduit instead of a transannular patch
What are the 2 surgical approaches to ToF?
- Valve sparing technique (surgically remove the infundibular stenosis and spare the valve)
- Transannular patch repair
What are key components to image for ToF surgery planning?
- Coronary artery anatomy
- Common AV valve morphology
- Number/location of VSDs
- RVOT anatomy
What are the 2 causes of supravalvar AS?
- Discrete narrowing at STJ
- Long segment narrowing in ascending aorta
Patients with supravalvar aortic stenosis generally have what gene defects?
Elastin arteriopathy (defect in the elastin gene)
7q11.23 microdeletion?
Williams
The 7q11.23 microdeletion seen in Williams syndrome includes what gene that results in some of the cardiac manifestations?
Elastin gene
Slow growth, feeding difficulties, periorbital edema, developmental delay, hypercalcemia, supravalvar aortic stenosis?
Williams syndrome
True or False: The abnormalities in elastin that lead to the arteriopathy which causes supravalvar aortic stenosis in Williams syndrome can cause narrowing in other large arteries throughout the body?
True
What are some other arteries which can have narrowing besides supravalvar aortic stenosis in patients with defects in the elastin gene (Williams syndrome)?
- Pulmonary arteries (40%)
- Coronary arteries (Ectasia, ostial obstruction from webs or fibrous ridges)
- Thoracic aorta (middle aortic syndrome)
- Abdominal aorta
- Head an neck vessels
- Mesenteric arteries
- Intracranial arteries
What is stenosis of the thoracic aorta called?
Middle aortic syndrome
What is middle aortic synddrome?
Narrowing in the aorta distal to the head vessels
What patients can get middle aortic syndrome?
Williams
How does middle aortic syndrome present?
HTN in the upper extremities with normal or low BP in lower extremities
What causes a widened pulse pressure and increased systolic BP in Williams patients?
Abnormal aortic distensibility
What often results from streaming of the high-velocity jet in supravalvar aortic stenosis?
Coanda effect
What is the Coanda effect?
Asymmetric jet in the aorta that adheres to the wall and preferentially streams into one of the head an neck vessels (usually innominate and right subclavian artery)
How does the Coanda effect present?
Blood pressure difference between the upper extremities (Right > Left)
What cause of HTN should you consider in patients with William’s syndrome?
Renal artery stenosis
True or False: Renal artery stenosis is often seen in association with middle aortic syndrome?
True
What BPs are elevated in bilateral renal artery stenosis?
All 4
What vital signs should be routinely measured in patients with Williams syndrome and other types of elastin arteriopathies?
4-extremity BP
True or False: Sinus node dysfunction occurs frequently in the post-operative period after Fontan palliation?
True
When you have a junctional rate that is faster than an atrial rate, does this imply AV block?
Not necessarily
What is the preferred mode of pacing to start with sinus node dysfunction following surgery?
AAI
Why is AAI pacing the preferred mode to start with for sinus node dysfunction following surgery?
- Provides AV synchrony
- Provides HR support
- Uses patients own conduction system
- Avoids uncoordinated ventricular contraction seen with ventricular pacing
What are indications for temporary pacing following surgery?
- Sinus node dysfunction (HR support)
- Slow junctional rhythm (HR support and AV synchrony)
- JET (AV synchrony)
- AV block
- Reentrant atrial tachycardia or AVRT (pace termination via rapid atrial pacing)
What is rapid atrial pacing used for in the post-operative period?
Terminate reentrant atrial or AV reciprocating tachycardias
What are the 2 pacing modes that can be used for post-operative heart block?
- VVI (adequate ventricular escape)
- DDD (adequate HR and AV synchrony)
*DDD usually preferred, but VVI can be used if AV synchrony isn’t needed for adequate hemodynamics and/or to monitor for return of intrinsic AV conduction
What pacing is preferred for sinus node dysfunction, junctional rhythm, or junctional tachycardia if the patient’s intrinsic AV conduction is intact?
AAI
What is preferred pacing mode for post-op AV block?
DDD
*VVI can be used in certain circumstances
80-90% of double chambered RV’s are associated with what?
VSDs (usually perimembranous)
What % of patients with VSDs have associated cardiac lesions?
50-60%
Acquired defects associated with VSD seen at late follow-up often relate towhat?
Outflow tracts (development of RVOTO or LVOTO)
What is the cause of a double chambered RV?
Anomalous muscle bands that separate the RV into a proximal high-pressure chamber and distal low-pressure chamber (resultant muscular obstruction to RV outflow)
When associated with a perimembranous VSD, how does double chambered RV develop?
Turbulent flow in ventricular outlet causes hypertrophy of endogenous trabecular tissue within the subinfundibular right ventricle
In double chambered RV, when the VSD shunts into the higher pressure portion of the RV, what is the physiology similar to?
ToF
Describe murmur/exam findings seen in double chambered RV?
- Subvalvular PS: Long, crescendo-decrescendo, over LUSB but lower than in isolated valvar stenosis
- No lock
- Palpable thrill common
True or False: Double chambered RV is a progressive condition with consequent RV hypertension and hypertrophy
True
How is double chambered RV managed?
Surgical resection and repair of associated defects
*Sometimes can be missed pre-operatively and found by persistent RV obstruction following VSD closure
How can a VSD result in aortic insufficiency?
Aortic valve leaflets prolapses to partially close VSD and gets distorted
Aortic arch obstruction is commonly associated with VSDs, especially if the VSD is caused by what?
Posterior malalignment of the outlet septum
Fixed splitting of S2 with diastolic rumble over tricuspid valve region?
Moderate-large ASD
Describe how NIRS monitoring works
- Similar to plethysmography of arterial pulse oximetry
- Infrared light emitted by diode within NIRS probe
- Sensor within probe measures amount of light absorbed the the area of interest
- Uses strong, nonpulsatile component to determine saturation in the tissue circulation
*Pulse ox uses weak pulsatile component to determine arterial saturation- often fails with poor tissue perfusion as pulsatile signal diminishes or disappears
What are some things that can make NIRS monitoring inaccuate?
- Poor perfusion (not as much impacts as in pulse ox)
- Motion artifact
- Ambient light noise like pulse ox
What are 2 common places to do NIRS monitoring?
Cerebral
Flank
What does the measurement of cerebral NIRS correspond to?
The level of oxyhemoglobin in the cerebral venous circulation
-Cerebral NIRS absorbs the majority of its light from the venous system based upon the wavelength used by the probe
With normal CO and oxygen delivery, cerebral NIRS should vary from the arterial oxygen saturation by what amount?
20-30%
A larger than normal difference between cerebral NIRS and arteria oxygen saturations can be indicative of what?
Oxygen delivery issues
NIRS can be used as a surrogate marker for what?
Mixed venous oxygen saturation
*Correlates well with SVC saturations in young infants
What is the most common cause of an elevated cerebral NIRS?
Hypercarbia
How does the pulmonary circulation respond to hypercarbia?
Vasoconstriction
How does the cerebral circulation respond to hypercarbia?
Vasodilation and increased blood flow
What happens to cerebral blood flow when the arterial CO2 level is decreased?
Cerebral blood flow decreases (can potentially acutely decrease intracranial pressure)
In post-op patients with cerebral NIRS monitoring, an elevation of NIRS without changes in other hemodynamic parameters should prompt investigation for what?
Hypercarbia
How does cerebral vasodilation and increased cerebral blood flow impact the NIRS?
Increased NIRS
-Increased cerebral blood flow results in elevated venous saturation
What may be helpful in children after Glenn to increase pulmonary blood flow?
Hypercarbia leading to cerebral vasodilation
What does hypocarbia do to pulmonary blood flow in Glenn patients?
Reduces it (by reducing cerebral blood flow)
What are 2 things that can cause an elevated NIRS?
- Hypercarbia
- Decreased O2 extraction in the brain due to significant brain injury (usually more subacute, but can happen acutely)
How does hypercarbia impact blood flow to the brain?
-Increases it by causing cerebral vasodilation
What is the classic carbonic anhydrase inhibitor?
Acetazolamide
How do carbonic anhydrase inhibitors work?
- Reversible inhibition of carbonic anhydrase in the proximal tubules of the kidneys
- Results in reduced hydrogen ion secretion and increased renal excretion of Na, K, Bicarb, and water
What do carbonic anhydrase inhibitors do to the serum bicarbonate level?
Lower it
What are carbonic anhydrase inhibitors used for?
- Metabolic alkalosis (lowers serum bicarbonate level, especially for ventilator weaning)
- Altitude sickness
What should be checked before giving acetazolamide?
pH
- Can have acidosis even in setting of alkalemia
- If serum pH <7.35-7.4, acetazolamide can worsen the acidosis
What can cause a primary metabolic alkalosis?
Chronic diuretic dependence
How do loop and thiazide diuretics cause a metabolic alkalosis?
Increase the renal excretion of Cl (negative anion)
How does the body compensate for metabolic alkalosis?
Respiratory acidosis- elevated PCO2
Why can a significant metabolic alkalosis be a barrier to weaning the ventilator?
It can suppress respiratory drive (body is trying to compensate with a respiratory acidosis by increasing PCO2)
What are options for treating metabolic alkalsis?
- Cl supplementation if Cl low
- Carbonic anhydrase inhibitor (increase bicarb secretion)
The initial dosing of acetazolamide should be over what time-frame?
24-72 hours (make sure that metabolic acidosis doesn’t develop with prolonged use)
When should acetazolamide be discontinued?
- pH <7.35
- Serum bicarbonate has decreased enough (to allow ventilator weaning, etc)
How do loop and thiazide diuretics impact a metabolic alkalosis?
Exacerbate it (by increased renal excretion of Cl)
What lab needs to be monitored in the setting of an ECG concerning for myopericarditis?
Troponin
What needs to be ruled out for adolescents with findings of myocardial ischemia?
Stimulant-induced coronary artery vasospasm
True or False: Exercise stress testing is contraindicated in the setting of acute myocarditis or pericarditis
True
What is the differential diagnosis for acute onset chest pain in an adolescent with elevated troponin levels?
- Myopericarditis
- Coronary artery abnormality (congenital or acquired like Kawasaki)
- Cardiomyopathy
- Drug toxicity
What testing may be needed to assess for a coronary artery abnormality in a teenager besides echo?
CTA or coronary aniography
True or False: Troponin is highly sensitive and specific for myocardial injury/necrosis and is superior to other cardiac enzymes like creatine kinase-MB or lactate dehydrogenase
True
What is the most common etiology for troponin elevation in adolescents who have acute chest pain and ECG changes?
Myopericarditis
What happens when you give someone with sinus tachycardia adenosine?
They may develop transient sinus slowing and AV block
What should you do for an infant with lethargy, tachycardia and decreased perfusion who has an ECG with normal sinus rhythm at a rate of 220?
Try a normal saline bolus, control any fevers, etc
True or False: Rates of sinus tachycardia in newborns frequently reach 220bpm and can go as high as 235bpm
True
What are typical AVRT rates for an infant?
250-300bpm range
*P-waves will be retrograde and hard to detect
What is the first line treatment for AVRT?
Adenosine
What should be done if adenosine doesn’t work in AVRT?
Try a higher dose (0.2mg/kg) and ensure good IV access and that it is given as a bolus followed by an IV flush
List forms of SVT seen in neonates/infants
AVRT
AVNRT
Flutter
EAT
How can adenosine be helpful in flutter?
It can block AV conduction long enough to see flutter waves
What is the management for a neonate in flutter?
Cardioversion
*Can use esmollol for rate control until further management possible
What is a clue to EAT?
P-wave axis is abnormal and not consistent with origin from the SA node
*Rates may vary
How can older patients (presentation after the neonatal period) present with tricuspid valve dysplasia?
- Abdominal pain and/or distension
- Peripheral edema
- Exertional dyspnea
- Palpitations (from new-onset arrhythmias)
What are physical exam findings consistent with tricuspid valve dysplasia?
- Murmur (valve regurgitation)
- Low-pitched rumble from severe stenosis or relative stenosis with severely regurgitant valve
- Hepatomegaly
- Peripheral edema (from increased CVP)
- JVD with a prominent V wave can sometimes be seen with severe TR and no interatrial shunt
- Possible cyanosis (if interatrial shunt, but usually subtle)
What is the surgical approach to tricuspid valve dysplasia?
Repair over replacement when feasible
True or False: A tricuspid valve cleft in isolation is usually repairable
True
How does a tricuspid valve Z-score of -2 impact tricuspid valve repair?
May limit options for replacement
True or False: A flail chord of the anterior leaflet of the tricuspid valve in isolation is usually repairable?
True
Describe Ebstein’s anomaly of the tricuspid valve
Large, sail-like anterior tricuspid valve leaflet with tethered septal leaflet and atrialized RV
What causes Ebstein’s anomaly?
Inadequate delamination of the TV from the RV during development
*Characterized by displacement of the annular attachments (hinge points) of the septal and inferior leaflets
True or False: The anterior leaflet of the tricuspid valve has its hingepoint in normal position at the AV groove in Ebstein’s anomaly?
True- the anterior leaflet forms at a different stage of development
*Normal insertion at hinge point, but is usually redundant, large and “sail-like” in appearance
How do older patients with Ebstein anomaly present?
Dyspnea, fatigue, palpitations, exercise intolerance or cyanosis with exercise
Murmur and arrhythmias frequent
True or False: A V wave is not common in Ebstein anomaly
True- large RA and atrialized RV usually dissipate the V wave
Why is Ebstein anomaly not associated with the same degree of hepatomegaly as a dysplastic tricuspid valve?
Because the V wave isn’t common…. Large RA and atrialized RV dissipate the V wave
What is the preferred surgical treatment of Ebstein anomaly?
Repair (replacement reserved for only most severe cases or cases that fail primary repair)
What should you consider with a fetal echo showing a twin gestation with discordant growth and polyhydramnios, ventricular hypertrophy and diastolic dysfunction?
Twin-twin transfusion syndrome
What type of twins develop twin-twin transfusion syndrome?
Monochorionic (share same placenta)
What % of monochorionic twins develop twin twin transfusion syndrome?
15%
What is the pathophysiology in twin-twin transfusion syndrome?
Not well understood, but vascular connections within the placenta permit the transfer of blood from the donor fetus to the recipient fetus
What happens to the donor twin in twin twin transfusion syndrome?
- Relative hypovolemia causes release of vasoactive mediators (vasopressin, renin-angiotensin)
- Leads to oliguria and low amniotic fluid levels
- Can’t visualize bladder
- Appears “stuck” up against the uterine wall
What happens to the recipient twin in twin twin transfusion syndrome?
- Hypervolemia leads to atrial/ventricular stretch
- Release of atrial and brain natriuretic peptides
- Increased urine output
- Polyhydramnios
- Freely mobile in large volume of amniotic fluid
What causes ventricular hypertrophy and dysfunction in the recipient twin in twin-twin tranfusion?
- Hypervolemia
- Abnormal concentrations of vasoactive mediators (elevated levels of renin and angiotensin cross from donor to recipient)
True or False: AVVR is common in the recipient twin in twin-twin tranfusion?
True
What finding in the ductus venosus is suggestive of poor RV compliance and diastolic dysfunction on echo?
Reversal of flow with atrial contraction
What finding in the umbilical artery Doppler is associated with a poor prognosis in twin-twin transfusion?
Absent or reversed diastolic flow in UA
True or False: Intracardiac structural abnormalities aren’t typically seen in the recipient heart in twin-twin transfusion?
True
The donor twin in twin-twin transfusion can have changes in what part of the heart?
RVOT
*Usually subtle: PI, smaller than expected pulmonary artery size, subvalvar PS, PS
What is the Quintero staging system?
Classification scheme to provide a standardized means to describe the severity of twin-twin transfusion syndrome
What can be done in less severe cases or at later gestation for twin twin transfusion syndrome?
- Expectant management
- Amioreduction (reduces uterine overdistention (RF for premature delivery and premature ROM
What is the only therapy at the addresses the underlying pathophysiology in twin-twin transfusion syndrome?
Laser ablation of anastomotic vessels
Maternal use of NSAIDs can cause what?
Constriction of the fetal ductus arteriosus
*Can impact the pulmonary vascular bed and RV (hypertrophy, dysfunction, TR)
What is selective fetal growth restriction?
When one twin’s estimate weight is < 10th % or if there is >25% discordance in the estimated twin weights
How do you distinguish between selective fetal growth restriction and twin-twin transfusion syndrome?
- Selective fetal growth restriction: Normally grown fetus has normal volume of amniotic fluid
- TTTS: Normally grown fetus has excess amniotic fluod
What causes selective fetal growth restriction?
Discordance in placental sharing
What is suggestive of twin-twin transfusion syndrome?
Discordance of amniotic fluid volumes
Inability to visualize fetal bladder
What causes twin-twin transfusion syndrome?
Unbalanced placental vascular anastomoses allow one twin to become hypovolemic (donor) while the other twin becomes hypervolemic (recipient)
True or False: Twin-twin transfusion syndrome is associated with a high risk of fetal mortality
True
What % of patients who have undergone an ASO for d-TGA may develop coronary artery stenosis?
5-10%
Describe the stenosis seen following an ASO for d-TGA?
- Late after ASO
- Many asymptomatic
- Tends to occur proximally at the ostium and progress slowly over time (allows for increased collateral flow from opposite coronary artery)
What is a concern with significant coronary stenosis following an ASO for d-TGA?
SCD related to ischemia and arrhythmias
What should be done for evaluation of the coronary arteries in older patients after ASO?
Options:
- TTE (if you can see proximal coronaries)
- Exercise stress test w/ echo
- CTA
- Coronary angiography
True or False: Mild-moderate branch PS is commonly seen after an ASO with the LeCompte manuever
True
True or False: Aortic root dilation is common in patients with dTGA who underwent an ASO?
True- possibly due to characteristics of the pulmonary tissue in that area
*Most experts hold a higher threshold for intervention in this situation (compared to a bicuspid valve or Marfan’s patient)
Describe circulation with SVR/PVR in utero
- RV dominant
- Low SVR due to placenta
- High PVR (lungs not inflated and filled with amniotic fluid)
What leads to a sudden lowering of the resistance in the pulmonary circulation after delivery?
- Severing of umbilical vessels
- Inflation of lungs with air
- Changes in oxygenation
What are factors that contribute to a postnatal decrease in PVR?
- Clearance of fetal lung fluid
- Surfactant secretion
- Relatively higher O2 tension
- Ventilation
What factors contribute to the postnatal increase in SVR?
- Removal of the placenta
- Catecholamine surge associated with birth
- Cold extrauterine environment
Describe the neonatal circulatory pattern in terms of SVR and PVR
- High SVR
- Reduced PVR
- LV dominant
What is the time period between birth and establishment of neonatal circulation?
Transitional
In a normal full-term infant, when does the ductus arteriosus functionally close?
By 2nd postnatal day
In a normal full-term infant, when does the RV pressure usually fall to adult levels by?
2-3 days after birth
Anatomical closure of the ductus occurs over what time frame?
2-3 weeks
Subaortic obstruction in the setting of d-malposed great vessels is associated with a risk of what?
Aortic coarctation
In a neonate with subaortic obstruction in the setting of d-malposed great vessels, what is a concern as the ductus closes?
CoA- increased risk in this anatomy and isthmus is vulnerable to constriction as PDA closes
An infant with DORV (d-malposed great vessels and a subpulmonary VSD) will behave like what?
d-TGA and large VSD
True or False: An infant with d-TGA and large VSD can develop CHF symptoms?
True- As PVR drops following birth, can develop pulmonary overcirculation with retractions, hepatomegaly, etc.
When can you see reverse differential cyanosis (O2 higher in lower extremities than upper)?
-dTGA and PDA with pulmonary HTN or CoA/IAA (but when the PDA closes, no more differential saturations)
Wide complex tachycardia with a RBBB morphology and superior axis (negative QRS in II, III and aVF) with ventriculo-arterial dissociation?
Left ventricular fascicular tachycardia (Belhassen tachycardia or verapamil-sensitive ventricular tachycardia)
What type of patients is left ventricular fascicular tachycardia usually seen in?
Young patients with a structurally normal heart
True or False: Left ventricular fascicular tachycardia rarely leads to tachycardia-induced cardiomyopathy or sudden death?
True
Describe left ventricular fascicular tachycardia
- Reentrant
- Usually originates from the posterior fascicle in the LV
- Utilizes slowly conducting verapamil-sensitive fibers in the posterior fascicle
What is the first-line management for acute treatment and prevention of recurrence in left ventricular fascicular tachycardia?
Verapamil
What is an option for long-term management in left ventricular fascicular tachycardia?
RF ablation
True or False: Adenosine can be effective in terminating left ventricular fascicular tachycardia?
True
True or False: Left ventricular fascicular tachycardia responds to lidocaine?
False
True or False: Vagal maneuvers will terminate a left ventricular fascicular tachycardia?
False
What are the characteristic findings on ECG in a left ventricular fascicular tachycardia?
RBBB
Superior axis
What medication is left ventricular tachycardia sensitive to?
Verapamil
The risk of atrial arrhythmias increases in adults with ASDs according to what 3 things?
- Age
- PA pressure
- LV dysfunction
How does LV dysfunction impact shunting across an ASD?
It may increase the L-R shunt and worsen atrial dilation
What factors contribute to LV dysfunction in the setting of an ASD?
- Abnormal IVS motion caused by chronic volume overload
- Decreased preload to LV
- Older age
What predisposes an older patient with a long-standing ASD to atrial arrhythmias?
- Long-standing hemodynamic overload and atrial stretch can cause geometrical and electrical remodeling of the heart
- Geometrical remodeling leads to interstitial fibrosis, increased myocyte size and altered cellular structure which predisposes to atrial arrhythmias
- Electrical remodeling prolong atrial refractoriness and slows conduction making the patient vulnerable to atrial arrhythmias
True or False: Atrial arrhythmias are less likely to occur after closure of ASDs during childhood?
True
RA and RV reverse remodeling occur within what time frame following ASD closure?
Within 1 year
*Closure at an older age may limit the degree of reverse remodeling
What can help to reduce the risk of post-procedural arrhythmias in older populations after ASD closure?
- MAZE
- EP mapping and ablation
True or False: DOE in the setting of an adult with an ASD improves after ASD closure?
True
Mild-moderate PA hypertension is seen in what % of patients with an untreated ASD?
5-10%
likely multifactorial etiology
If an adult with an ASD has elevated PVR, what should be done?
Aggressive pulmonary hypertension therapy (may allow for defect to be closed)
*If progresses to Eisenmenger, ASD closure isn’t indicated
What needs to be ruled out in someone who has suffered an embolic stroke?
ASD (+/- atrial arrhythmias)
What reduces the risk of atrial arrhythmias in someone with an ASD?
Closure of ASD at a younger age
What does hybrid palliation for neonates with HLHS consist of?
- Bilateral PA bands
- Ductal stenting
- BAS usually needed for unobstructed L-R shunting through atrial septum
How is ductal stenting done for a hybrid palliation for HLHS?
- Femoral venous access
- Direct access to MPA through median sternotomy
If you have aliasing of the Doppler signal at the level of the aortic valve (blood flow velocities exceed the Nyquist limit of the transducer), what can be masked?
Supravalvar AS
How does terbutaline work?
Selective B2-adrenergic agonist
What is terbutaline used for?
Refractory status asthamticus
Which B receptors does terbutaline act on?
- Primarily B2 receptors in bronchial smooth muscle
- Can have effect on B1 receptors in ventricular myocardium
What cardiac effects can B receptors have?
- Persistent tachycardia (B1 receptors in ventricular myocardium)
- Diastolic hypotension (peripheral blood vessel B stimulation)
True or False: There is risk for myocardial ischemia in patients on higher-dose terbutaline infusions?
True- Some routinely measure Tn and CK-MB along with serial ECGs
- Literature is not specific…can get elevations in labs, but no definitive evidence that treatment with continuous B-agonist infusion predisposes to ischemia
- No definitive guidelines for labs to ECG screening in patients on continuous IV B-agonist therapy
True or False: Terbutaline (and other B-agonists used to treat asthma) can cause tachycardia and hypotension, but it is very rare for them to precipitate myocardial ischemia?
True
What are early complications following AVSD repair?
- AV block (may need pacemaker)
- Unplanned reoperation or reintervention (left AVVR, residual VSD)
- PAH (less common now because patients often undergo surgery younger)
Progression of left AVVR following AVSD repair with need for reoperation occurs in what % of patients?
10-20%
*Of those who undergo reoperation, a second reoperation may be needed in 25%
What is the most common indication for late reoperation after AVSD repair?
Left AVVR
What is the second most common indication for late reoperation after AVSD repair?
LVOTO
What predisposes to the development of LVOTO in AVSD patients?
Narrow and elongated outflow tract with an abnormal outlet angle that predisposes to the development of obstruction
What are the class I indications for mitral valve repair per adult guideliens?
- Presence of symptoms
- LV dysfunction (LVEF 30-60% or LVESD >40mm in adult sized patients or serial echos with progressive change in these parameters))
What are the class IIa indications for mitral valve repair per adult guidlines?
-Asymptomatic patients with preserved LV function and new-onset a-fib or resting pulmonary HTN (PASP >50mmHg)
True or False: Long-standing volume overload of the LV due to MR leads to irreversible LV dysfunction and poorer prognosis
True
Narrowly split S2 with loud P2?
Pulmonary HTN
What are early post-operative complications following AVSD repair?
- Residual intracardiac shunts
- Left AVVR
- Conduction disturbances
Following initial repair of complete AVSD, 10-15% of patients will require reoperation within 10-15 years to address what?
- Left AVVR
- LVOTO
What are the criteria for reintervention for left AVVR following AVSD repair?
- Symptoms
- LV dysfunction
- Progressive LV enlargement
- Secondary pulmonary HTN
True or False: Pulmonary vein stenosis is often progressive and recurrent?
True
Pulmonary vein stenosis is more common in which infants?
Premature with CLD (like BPD)
Which veins are at increased risk for pulmonary vein stenosis?
No specific vein
True or False: Pulmonary vein stenosis often progresses distally over time?
True
What is the pathophysiology of congenital pulmonary vein stenosis related to?
Intimal hyperplasia secondary to proliferation of myofibroblastic cells in the pulmonary veins
How do patients with pulmonary vein stenosis present?
- Recurrent respiratory symptoms due to interstitial edema (isolated to lung areas with vein stenosis or more diffuse)
- Progressive symptoms of pulmonary HTN
What are some ways pulmonary vein stenosis can be diagnosed?
- CXR: Edema/hyperinflation
- Echo
- CT: Often don’t need sedation
- MRI: Need sedation usually
- Cath: Diagnostic and therapeutic
How is pulmonary vein stenosis treated?
Direct angioplasty +/- stenting (possibly with drug-eluting balloons and stents)
What is the medical management of pulmonary vein stenosis?
- Diuretics for pulmonary edema
- Can consider pulmonary vasodilators or oxygen, but could potentially worsen pulmonary edema by dilated proximal to a fixed downstream obstruction
True or False: Surgery is often not pursued for congenital pulmonary vein stenosis because of the progressive and recurrent nature of the disease?
True
- Also, areas of stenosis are often too distal to access by surgery
- Some centers do surgery for proximal lesions with “sutureless” techniques near LA junction
True or False: Outcomes in infants with pulmonary vein stenosis are usually poor?
True- often refractory to medical treatment and interventions
*Stenosis in multiple veins associated with high mortality rate before age 5
What are 2 risk factors for developing pulmonary vein stenosis?
- Prematurity
- BPD
What is a chronic inflammatory disease or scar of the pericardium that can be secondary to infection, connective tissue disorders, prior cardiac surgeries or neoplastic disorders?
Constrictive pericarditis
True or False: The myocardium is typically normal in constrictive pericarditis?
True (may show some signs of atrophy in long-standing CP)
What causes restrictive cardiomyopathy?
- Idiopathic
- Infiltrative or inflammatory process
- Genetic disease
What are presenting symptoms in both restrictive cardiomyopathy and constrictive pericarditis?
-Diastolic HF: SOB, exercise intolerance, ascites (may be out of proportion to LE edema), JVD
What might patients with restrictive cardiomyopathy or constrictive pericarditis be diagnosed with prior to making the correct diagnosis?
- Respiratory disorders: Pulmonary symptoms precede other findings
- GI illness: If hepatomegaly or ascites are prominent presenting features
What are symptoms unique to restrictive cardiomyopathy and not typically seen in constrictive pericarditis?
- Arrhythmias
- Syncope
- Sudden death
What are findings on CXR in restrictive cardiomyopathy and constrictive pericarditis?
- Normal
- Mild-moderate cardiomegaly (atrial enlargement)
- Pulmonary venous congestion
- Decreased lung volumes (with significant ascites)
What ECG findings are seen in restrictive cardiomyopathy and constrictive pericarditis?
- Biatrial anlargement
- ST-T wave abnormalities
What ECG finding is more common in restrictive cardiomyopathy compared to constrictive pericarditis?
Ventricular hypertrophy
A low-voltage QRS is more common in which: Restrictive cardiomyopathy or constrictive pericarditis?
Constrictive pericarditis
Does restrictive cardiomyopathy or constrictive pericarditis have mildly increased wall thickness and decreased ventricular function?
Restrictive cardiomyopathy
*But both can have preserved ventricular size and function
True or False: Biatrial enlargement is a hallmark echo finding in restrictive cardiomyopathy and usually present in constrictive pericarditis (but to a lesser degree)?
True
True or False: Pericardial thickening is absent in constrictive pericarditis?
False- may be seen in constrictive pericarditis
*Absent in restrictive cardiomyopathy
When a septal bounce is observed does it suggest constrictive pericarditis or restrictive cardiomyopathy?
Constrictive pericarditis
Which has significant respiratory variation in Doppler inflow of the mitral/tricuspid valves, restrictive cardiomyopathy or constrictive pericarditis?
Constrictive pericarditis
In constrictive pericarditis, the how is the TDI E’ velocity of the lateral MV annulus change relative to the septal E’ velocity?
Lateral MV E’ may be decreased relative to septal E’
*Due to tethering of the annulus to the pericardium- annulus reversus (not seen in restrictive cardiomyopathy)
True or False: LV enlargement is absent in both constrictive pericarditis and restrictive cardiomyopathy?
True
True or False: LV systolic dysfunction is absent in both constrictive pericarditis and restrictive cardiomyopathy?
False- absent in CP, usually absent in RC
Biatrial enlargement is always present in which, constrictive pericarditis or restrictive cardiomyopathy?
RC (usually present in CP)
Which do you see pericardial thickening, constrictive pericarditis or restrictive cardiomyopathy?
Constrictive pericarditis
Which can have ventricular septal bounce, constrictive pericarditis or restrictive cardiomyopathy?
CP
Which has respiratory variation of tricuspid and mitral inflows, constrictive pericarditis or restrictive cardiomyopathy?
CP
What is seen on CMR in constrictive pericarditis that can be helpful to distinguish between constrictive pericarditis and restrictive cardiomyopathy?
Thickened pericardium which may be inflamed (not seen in restrictive cardiomyopathy)
What is the advantage of CMR over CT when trying to distinguish between constrictive pericarditis and restrictive cardiomyopathy?
- CMR: Can see both the pericardial thickening and calcification as well as evaluation of the myocardium
- CMR would be a disadvantage if sedation or anesthesia were required
True or False: Cardiac catheterization carries a significant risk in patients with restrictive cardiomyopathy?
True
What is the difference in end diastolic pressures in the ventricles seen in diagnostic catheterization between restrictive cardiomyopathy and constrictive pericarditis?
- CP: EDP usually equal in LV/RV
- RC: Higher LVEDP than RVEDP
What is the difference in RVSP or pulmonary pressures in the ventricles seen in diagnostic catheterization between restrictive cardiomyopathy and constrictive pericarditis?
- CP: Unusual for RVSP to be > systemic pressure
- RC: Mod-severe pulmonary HTN
Is pulmonary HTN more common in restrictive cardiomyopathy or constrictive pericarditis?
RC
What are typical PASP values in restrictive cardiomyopathy v. constrictive pericarditis?
- RC: Often >50mmHg and may be suprasystemic
- CP: Usually <50mmHg
True or False: An endomyocardial biopsy can be diagnostic for restrictive cardiomyopathy v. constrictive pericarditis in children?
False
When might a cath be necessary to distinguish between restrictive cardiomyopathy and constrictive pericarditis?
Concern for pulmonary HTN and significantly elevated PVR
What is the treatment for constrictive pericarditis?
Complete pericardiectomy
*May see rapid improvement if the pericardium can be completely removed
What is the only definitive treatment for restrictive cardiomyopathy?
Transplant
- 50% of patients will die or require transplant within 2 years of being diagnosed
- Can try medical management to help with symptoms while awaiting transplant, but mechanical support can be challenging with this
If you can’t distinguish between restrictive cardiomyopathy and constrictive pericarditis by echo, what should be done next in the workup?
CT or MRI (v. cath which carries increased risk to patient)
What is the most common anomaly of systemic venous connections?
LSVC to CS
*Creates no physiologic derangement, if isolated considered a normal variant
What circumstances does an LSVC to CS become clinically relevant?
Placement of a central line, pacemaker lead or ICD lead
True or False: LSVC to CS has a higher prevalence in patients with CHD?
True
What is typically the first clue on echo to the presence of an LSVC to CS?
Dilated CS in the posterior left AV groove on PSLA imaging
What is the embryologic origin of the CS and LSVC if present?
Left common cardinal vein
*Why a persistent LSVC normally continues with CS
Drainage of a persistent LSVC to LA can only occur under what circumstances?
If CS is partly or completely unroofed (partial or complete absence of the common wall between the LA and CS)
Bilateral SVCs draining to both sides of the atrial mass has the highest incidence in what anatomic situation?
Isometric atrial appendages
*Or other complex CHD
Does isometric right or left atrial appendages result in the CS being absent and bilateral SVC connections to the right and left sided morphologic RA (“anatomically normal”)?
Right
*CS is a component of the morphologically left AV junction
Does isometric right or left atrial appendages result in bilateral SVC connections being “anomalous” on each side?
Left
What procedural implications are present when there are bilateral SVCs?
- Cannulation site in OR
- Vascular access for cath
- If single ventricle, need bilateral bidirectional superior cavopulmonary anastomoses
What is the drainage pathway of the right sided head and neck vessels with a persistent left SVC without a right SVC?
Right sided head and neck vessels drain to the right innominate vein to the left SVC then via a dilated CS to the RA
A right SVC draining into both atria is closely related to what?
Sinus venosus defect
There is a higher occurrence of systemic venous anomalies in patients with what form of complex CHD?
Heterotaxy
In pediatrics, what things are associated with atrial fibrillation?
- CHD
- Cardiomyopathy
- Channelopathy
- WPW
- Hyperthyroidism
- Drug/alcohol abuse
What proportion of WPW patients may have atrial fibrillation?
1/3
What do many pediatric/young adult patients with paroxysmal lone atrial fibrillation have?
Reentrant SVT (a-fib degenerates from reentrant tachycardia)
What defines sustained slow pathway conduction on an EP study?
PR interval > RR interval
Sustained slow pathway conduction on an EP study is predictive of what?
AVNRT
True or False: If present, treatment with ablation of AVNRT or AVRT may cure atrial fibrillation?
True
What is frequently done to treat atrial fibrillation in adults?
Ablation performing pulmonary vein isolation
What type of ablation is used for typical atrial flutter?
Cavotricuspid isthmus line
Lone atrial fibrillation appears to degenerate from a more common reentrant tachycardia in what % of pediatric patients and young adults?
30-40%
Primary intravascular stent implantation is indicated for the treatment of significant proximal pulmonary artery stenosis in what circumstances?
If vessel is large enough to accommodate a stent that is capable of being dilated to an adult vessel diameter
The recommendation to stent a branch pulmonary artery is when the flow ratio is what on a perfusion scan or other imaging modality?
35%:65%
*Many centers don’t treat until this is larger however
What are 2 signs by echo that are consistent with significant pulmonary artery stenosis?
- Measurable gradient > 20-30mmHg
- RVSP > 1/2 to 2/3 systemic pressure
If inserting a branch PA stent, what is the goal?
That the maximal diameter of the stent is compatible with an adult-sized PA (once maximally dialted)
True or False: Balloon angioplasty is not as effective as stent placement for branch pulmonary artery stenosis?
True
What are the most common causes of congenital complete AV block?
- Autoimmune antibodies (maternal SLE, Sjogren)
- CHD (cc-TGA, heterotaxy)
- Genetic syndromes (Holt-Oram)
- Idiopathic
Upper limb abnormalities, CHD (especially ASD) and rhythm abnormalities (sinus node dysfunction, AV conduction deficits)?
Holt-Oram
How is Holt-Oram inherited?
- De novo mutation
- AD
What is the mutation associated with Holt-Oram?
TBX5
What kind of antibodies can be seen in patients with congenital complete AV block?
Maternal antibodies to Ro/SSA (Sjogren syndrome related antigen A)
What are the most common known causes of congenital AV block?
Maternal autoimmune disorders like SLE and Sjogren
KCNQ1
LQTS type 1
PKP2
ARVD
What is the definition of a well-trained athlete?
Regular and long-term intensive exercise (minimum 4 hours per week)
Athletes often have ECG changes showing what 2 things?
- Cardiac chamber enlargement
2. Increased vagal tone
What is the J point?
Junction between the termination of the QRS complex and beginning of the ST segment
True or False: J-point elevation and J-point elevation associated with early repolarization is considered normal?
True
What is the difference in early repolarization between white and African athletes?
- White: Concave ST elevation with upright subsequent T waves
- African: Convex ST elevation with T-wave inversion following J-point elevation
ST elevation in leads V1-V3 with associated high risk of SCD?
Brugada
How do you distinguish between early repolarization and Brugada?
-Ratio of the height of the ST segment at the J point (STJ) compared to the height of the ST segment at 80msec after J point (ST80)
<1 in early repolarization
>1 Brugada
List normal ECG findings in athletes
- Increased QRS voltage for LVH or RVH
- Incomplete RBBB
- Early repolarization/ST segment elevation
- ST elevation followed by T-wave inversion V1-V4 in black athletes
- T-wave inversion V1-V3 age <16 years
- Sinus bradycardia or arrhythmia
- Ectopic atrial or junctional rhythm
- First degree AV block
- Mobitz Type 1 2 degree AV block
Do athletes with normal ECG changes need any further workup?
No- As along as asymptomatic with no family history of inherited heart disease or SCD
List borderline ECG findings in athletes
- LAD
- LAE
- RAD
- RAE
- Complete RBBB
When do athletes with borderline ECG findings require further workup?
If there are 2 or more findings (if 1 in isolation, no further workup needed if asymptomatic with negative FHx for inherited heart disease and SCD)
List abnormal ECG findings in athletes which prompt further evaluation
- T wave inversion
- ST segment depression
- Pathologic Q waves
- Complete LBBB
- QRS greater or equal to 140msec
- Epsilon wave
- Ventricular pre-excitation
- Prolonged QT interval
- Brugada Type 1 pattern
- Profound sinus bradycardia <30bpm
- PR interval greater or equal to 400msec
- Mobitz Type II second degree AV block
- Third degree AV block
- Greater or equal to 2 PVCs
- Atrial tachyarrhythmias
- Ventricular arrhythmias
What defines LAE?
- Negative portion of P-wave in V1 greater or equal to 0.1mV in depth and greater or equal to 40msec duration
- Also prolonged P-wave duration of greater 120msec in leads I or II
What defines RAE?
P-wave amplitude greater than or equal to 2.5mm in leads II, III or aVF
What defines LAD?
-30 to -90 degrees
What defines RAD?
> 115 degrees (some say >120)
What defines RVH?
Sum or R-wave in V1 and S-wave in V5/V6 grater ot equal to 1.05mV
*Also look at RAD >120
What is considered a normal QTc?
<470msec men and <480msec women
What is a complete LBBB?
QRS greater or equal to 120msec with predominantly negative QRS in V1 (QS or rS) and upright monophasic R-wave in 1 and V6
What is a complete RBBB?
RSR pattern in anterior precordial leads with QRS >120msec
What is an intraventricular conduction delay?
Any QRS duration >120msec including RBBB and LBBB
*Alt is QRS > 140 or complete LBBB
What is a pathological Q-wave?
> 40msec in duration or <25% height of ensuing R wave
- Alt is >0.4mV deep in any lead except III and aVR
- Alt is >0.3mV deep and/or >40msec duration in >/= 2 leads except III and aVR
What is significant T-wave inversion?
> 1mm in depth in 2+ leads V2-V6, II and aVF or I and aVL (excludes III, AVR and V1)
*Alt is >2mm in >/=2 adjacent leads
What is ST segment depression?
> /= 0.5mm deep in >/= 2 leads
What is ventricular prexcitation?
PR interval <120msec with delta wave
What happens to the MCA PI in fetuses with HLHS?
Decreased
What happenes to the UA PI in fetuses with HLHS?
Increased or normal
What happens to the cerebroplacental resistance in fetuses with HLHS?
Decreased
Cerebral and placental resistance can be assessed by using what?
Pulsatility index from interrogating cerebral and placental arteries (respectively)
Normal Doppler waveforms in the cerebral and placental arteries of fetuses in the 2nd/3rd trimesters show wht?
Pulsatile flow with a peak in systole and continuous forward flow through the cardiac cycle
How is the pulsatility index calculated?
(Peak systolic velocity-end diastolic velocity)/Mean velocity
True or False: Normal pulsatility indices vary by gestational age?
True
What happens to the UA PI through gestation?
Decreases
What happens to the MCA PI through gestation?
Increases, then decreases in 3rd trimester
What are PI used to assess on fetal echo?
Downstream resistance
What are things that affect PI on fetal echo?
- CO
- Viscosity
- Vascular obstruction
What is the cerebroplacental resistance?
Ratio of MCA-PI to UA-PI
What does a low cerebroplacental resistance mean?
- Decrease in MCA-PI
- Increase in UA-PI
- Both of above
*Associated with poorer outcomes
What happens to the MCA-PI in fetuses with TGA?
Normal (can be decreased in some studies)
What happens to the MCA-PI in pulmonary atresia?
Increased
What causes the decrease in MCA-PI in HLHS?
- Decreased cerebral resistance caused by hypoxemia or inadequate blood flow
- Just decreased cerebral blood flow
- Decreased SpO2 in cerebral blood flow may less of a factor as SV babies with PA have increased MCA-PI
- Restriction in blood flow due to retrograde path of flow/anatomic narrowing likely important factor
What is an potential explanation for the decreased head circumferences seen pre and post natally with HLHS and the adverse neurodevelopmental outcomes in this group?
Decreased cerebral blood flow
True or False: The UA-PI in fetuses with HLHS is variable?
True- Some are increased, others normal
What happens to the placental resistance in fetuses with IUGR?
Increases- Compensatory and considered a “brain-sparing” response
There is an association between increased placental resistance and what in babies with HLHS?
Decreased birth weight
Regardless of the UA-PI being normal or increased in infants with HLHS, what happens to the cerebroplacental resistance?
Decreases (due to decrease in MCA-PI)
What mediates hypotension in the setting of a widened pulse pressure, tachycardia, warm extremities, bounding pulses and high CVP?
Vasodilation
What causes vasodilatory hypotension following heart transplant?
Systemic inflammatory response related to cytokine release and endothelial injury following CPB
True or False: Milrinone (especially at higher doses) can exacerbate vasodilatory hypotension?
True
What vasoactive can help to increase BP by causing vasoconstriction?
Vasopressin
Under what circumstances would fluid boluses not help hypotension?
If the CVP is already high
How does milrinone work?
Phosphodiesterase inhibitor
How does milrinone cause increased inotropy?
More efficient release of myocardial Ca stores
Why does milrinone cause hypotension?
Reduction in SVR
What is the half life of milrinone?
2-3 hours
*Need to be mindful if trying to decrease dose to due adverse side effects
At lower doses, how does epinephrine work?
Activates B1 adrenergic receptors increasing inotropy
At higher doses, how does epinephrine work?
Alpha adrenergic receptors can be activated
For a patient on long-term beta blockade, why might low-does epinephrine not work as well?
Low-dose epinephrine works via activation of non-selective B1-adrenergic receptors
What adverse effect do you have to be mindful of with epinephrine in a post-operative patient?
Tachydysrhythmias
Vasopressin is indicated primarily in what type of shock?
Vasodilatory (like septic)
How does vasopressin work?
- Binds to vasopressin-specific, membrane-bound V1 receptors on smooth muscles
- Binding causes vasoconstriction by increasing intracellular Ca levels via phosphoinositide pathway
- Blocks K-sensitive ATP channels in dose-dependent manner
- Increases cGMP levels by decreasing inducible NO-synthase enzymes
*Also has roles in osmo-regulatory balance
True or False: Vasopressin has little to no cardiovascular effect outside of septic shock and other states that may cause endothelial injury leading to vasodilation
True
True or False: The action of vasopressin is independent of pH?
True
*Unlike other vasoactives like epinephrine
What situation do you have to be cautious using vasopressin in?
Those with compromised blood flow to the GI track (NEC, etc.)
*Due to potential vasoconstriction of the splanchnic bed
What is the usual dose of vasopressin for shock in pediatrics?
0.01 to 0.1U/kg/hr
What vasoactive is indicated in pediatric septic shock and other states resulting in endothelial injury leading to poor vascular tone?
Vasopressin
Which vasoactive isn’t pH dependent and equally effective in acidotic states?
Vasopressin
What should be done for DORV with malposed great arteries, VSD closely associated with pulmonary valve (subpulmonary VSD), no subpulmonary stenosis and crowding of the subaortic region?
ASO with baffle from LV to neo-aortic lvae with LeCompte
What procedures are used in cases of subpulmonary obstruction with transposed (or malposed) great arteries?
Nikaidoh and Rastelli
What is the Rastelli procedure?
LV-aortic baffle with RV-PA conduit
What is the Nikaidoh procedure?
Aortic root translocation
What is a long-term issue with both the Rastelli and Nikaidoh procedures?
Conduits need to be replaced eventually
What can be done for infants with DORV and subpulmonary VSD with coarctation if they can’t undergo complete repair after birth?
PA bands with arch augmentation (limits pulmonary overcirculation and ensures adequate systemic flow)
*Would be hypoxic after this pending atrial/ventricular mixing
What surgeries are used in cases of subpulmonary obstruction with VSD and transposed (or malpsoed) great arteries?
Nikaidoh
Rastelli
How is DORV with subpulmonary VSD repaired?
ASO and baffle from LV to neo-aorta
*Subaortic or arch obstruction may also be addressed at time of repair
RBBB with covedlike ST segment elevation in leads V1 and V2?
Brugada
What is the most commonly involved ion channel in Brugada?
Na
What is the most common mutation in Brugada?
Loss of function in SCN5A
When do patients with Brugada tend to have ventricular arrhythmias and SCD?
- Sleep
- Following a heavy meal
- During a febrile illness
When does Brugada usually present?
- Adulthood (3-4 decade)
* Has been diagnosed in neonates shortly after birth
What is the mean age of SCD in Brugada?
40
True or False: A baseline ECG in Brugada patients can be normal?
True
If a patient with Brugada has a normal baseline ECG, what can be done to bring out the Brugada pattern?
- Drug challenge (Procainamide, flecainide)
* Febrile illness can also bring out pattern
What should be done for an adolescent with normal ECG in the setting of a history of syncope and family history of Brugada?
Procainamide challenge
What 2 conditions is an epinephrine drug challenge diagnostically helpful?
- LQTS (paradoxical QT prolongation)
- CPVT (triggers ventricular arrhythmias)
What is the classic CPVT arrhythmia?
Biventricular ventricular tachycardia
How is exercise stress testing helpful for diagnosis in CPVT?
See increasing ventricular ectopy and bidirectional ventricular tachycardia
How is exercise stress testing helpful in LQTS?
Can see a paradoxical QT prolongation during exercise
What is the classic ECG finding in Brugada syndrome?
RBBB with coved like ST segment elevation
How can the Brugada pattern be brought out in at-risk patients with normal ECGs?
Procainamide challenge
What age group is more likely to present with incomplete or atypical Kawasaki disease?
Infants < 6 months
What needs to be considered in infants <6 months with persistent fever and irritability?
Kawasaki
True or False: Infants < 6 months are particularly susceptible to the development of coronary abnormalities in the setting of Kawasaki, even if treated within 10 days?
True
When should incomplete Kawasaki disease be considered in infants?
Fever for 7+ days without other explanations
Certain lab findings as well
Sterile pyuria is especially common in Kawasaki patients in what age group?
<1 year
- Occurs in 30-80% of Kawasaki patients overall
- Pyuria may be associated with more severe inflammatory reactions
True or False: Almost all Kawasaki disease patients have elevation in CRP and ESR?
True
*If CRP/ESR aren’t elevated prior to IVIG, diagnosis of Kawasaki Disease is unlikely
What are the lab findings which support a diagnosis of incomplete Kawasaki?
- Sterile pyuria
- Anemia
- High platelet count after 7 days of fever
- Low albumin
- Elevated WBC
- Elevated ALT
An infant needs how many lab findings of incomplete Kawasaki to receive treatment?
3
True or False: Thrombocytopenia is common in acute Kawasaki disease?
False- may occur in first 1-2 weeks of illness
*Thrombocytopenia is associated with more severe disease and increases risk of developing coronary artery abnormalities
What lab finding is a “red flag” for increased disease severity in a patient diagnosed with acute Kawasaki disease?
Thrombocytopenia
What echo findings support a diagnosis of Kawasaki disease and prompt treatment in incomplete or atypical Kawasaki disease?
- Coronary artery dilation (especially proximal LAD or RCA)
- LV dysfunction
- MR
- Pericardial effusion
Kawasaki disease should be considered in infants with what “non-traditional” clinical circumstances?
- Prolonged fever and unexplained aseptic meningitis
- Unexplained or culture negative shock
- Cervical lymphadenitis unresponsive to antibiotics
- Retropharyngeal or parapharyngeal phlegmon unresponsive to antibiotic therapy
What is Group 1 PH?
Idiopathic/hereditary, CHD and others
What is Group 2 PH?
Postcapillary PH caused by left sided heart disease and others
What is Group 3 PH?
Lung disease
What is Group 4 PH?
Thromboembolic diseases
What is Group 5 PH?
Miscellaneous causes
What are the 3 most common causes of pediatric pulmonary hypertension?
Idiopathic/hereditary
CHD
CLD
What 2 causes of pulmonary hypertension usually occur during adulthood?
Thromboembolic
Multisystem disorder
What are the most common symptoms of pulmonary hypertension?
Dyspnea and fatigue with activity
Besides dyspnea and fatigue with activity, what are other presenting symptoms in kids with pulmonary hypertension?
Syncope (30%)
Seizures
Arrhythmias
Cyanosis
What are some physical exam findings seen in pulmonary hypertension?
RV heave Loud P2 component of S2 Systolic click (from dilated MPA) Holosystolic murmur (TR) Elevated JVP Hepatomegaly Ascites Peripheral edema
What has to be done prior to making a diagnosis of idiopathic pulmonary hypertension?
Complete evaluation for secondary causes of PAH
What things are echo are important to note in pulmonary hypertension?
- Structural heart defects that could be playing a role
- Estimation of RV/PA pressure
- RV size and function
- RA size
- PFO shunt direction
What is the gold standard for evaluation and management of pulmonary arterial hypertension?
Cardiac catheterization with acute vasoreactivity testing
*Should be done prior to initiation of therapy
Besides echo and cath, what testing should be done in the workup of pulmonary hypertension?
- PFTs
- Lung imaging (CT w/ and w/o contrast)
- Baseline BNP
- 6-minute walk test
What testing is helpful to monitor response to treatment and functional capacity in pulmonary hypertension?
- BNP
- 6 minute walk
True or False: Exercise stress testing can be high risk for patients with pulmonary hypertension?
True
What does a high-resolution CT help identify in pulmonary HTN?
- Lung parenchymal disease
- ILD
- Veno-occlusive disease
- Pulmonary vein stenosis
- Pulmonary AVM
What testing should be considered for patients with a poor response to pulmonary arterial hypertension treatment?
Sleep study to assess for central/obstructive or mixed causes of apnea
What testing should be done if chronic thromboembolic disease is suspected to be the cause of pulmonary arterial hypertension?
Hypercoagulability
What forms the great arteries and head and neck arteries in human embryos?
Aortic arches (6 paired vascular structures)
Where are the aortic arches located in fetuses?
Ventral to the dorsal aorta
Where do the aortic arches in fetuses arise from?
Rudimentary aortic sac
What structure does a PDA arise from?
Persistence of the left sixth aortic arch
Besides a PDA, what other structure is formed from the left sixth aortic arch?
LPA
What does persistence of the right 4th aortic arch result in?
Right aortic arch
What happens if there is persistence of the right and left fourth aortic arch?
Double aortic arch
What leads to a right aortic arch embryologically?
If there is persistence of the right fourth aortic arch and a break in the left fourth aortic arch
What do the seventh intersegmental arteries contribute to the formation of?
Subclavian arteries
What does the left third aortic arch contribute to?
Formation of the left common carotid and proximal portions of the left internal carotid arteries
What forms the ductus arteriosus?
Left sixth aortic arch
Pulmonary edema in a patient on VA ECMO is an indication for what?
Atrial septostomy
What are the downstream effects of the LV being unable to eject?
- LA HTN
- Pulmonary venous HTN
- Pulmonary edema
- Potential for pulmonary hemorrhage
How does creation of an ASD help with pulmonary edema in a patient on VA ECMO?
Allows LA to decompress
What is usually needed for creation of an ASD in someone on VA ECMO?
- Transseptal puncture
- Older patient with thin septum may just need a static balloon dilation or stent placement
RBBB + ST segment elevation in V1/V2?
Brugada syndrome
Brugada is most commonly caused by a loss-of-function mutation in what gene?
SCN5A
What can unmask the Brugada pattern on ECG and trigger ventricular arrhythmias?
Febrile illness
What is very important in a patient who has Brugada syndrome and is sick?
Aggressive control of fevers
Diffuse ST segment elevations with PR depression?
Pericarditis
Significant ST segment elevation in the inferolateral and anterior leads with ST segment depression in the septal leads?
Severe myocarditis or ischemia
J-point elevation and upward concave ST-segment elevation?
Early repolarization
When are patients with Brugada syndrome at risk for ventricular arrhythmias?
During febrile illness
What is the preferred method of delivery in pregnant women with CHD and why?
- Vaginal
- Less frequent hemorrhagic complications and fewer thrombotic and infectious risks
A C-section is indicated for pregnant women with an aortic aneurysm greater than what?
45mm
Why is it not uncommon to see a dilated sinus of Valsalva in patients who have had a Ross procedure?
Translocation of “pulmonary” tissue into the aortic position in the autograft
Bicuspid aortic valves are known to cause microfibrillar disarray that leads to what?
Ascending aortic aneurysm
An LVEF < what would be an indication for C-section?
40%
What should be considered as possible causes for LV dysfunction in someone who has undergone a Ross procedure?
- Issues with re-implanted coronaries
- Ventriculo-ventricular interactions related to RV dilation and severe PI
True or False: Severe pulmonary hypertension is considered a contraindication to pregnancy?
True
True or False: Generally, regurgitant lesions are well tolerated in pregnancy?
True
*Severe PI (like in repaired ToF with transannular patch) often undergo successful pregnancies
Women with CHD and pregnancy should be managed in what type of program?
Multidisciplinary with cardiologist and high-risk OB
What are considerations for primary C-section related to CHD?
- Aortic aneurysm >45mm
- LV dysfunction with LVEF <40%
- Severe pulmonary hypertension
Common cardiac exam in all types of ASDs?
- Fixed split S2
- Systolic ejection murmur (relative PS caused by increased flow across PV due L-R atrial shunt)
Blowing holosystolic murmur at the apex?
MR
What finding on exam suggests MVP with MR?
Click with a blowing holosystolic murmur at the apex
MR is more common in patients with what type of ASD?
Primum- Cleft in anterior MV leaflet
What ECG findings would be suggestive of a primum ASD?
Left superior axis deviation
*Some may have a mildly prolonged PR interval or 1st degree heart block
What causes the abnormal QRS axis and higher rate or prolonged PR interval in primum ASDs?
Abnormal location of the conduction system
*Primum ASDs are a form of an endocardial cushion defect
What ECG findings fit with a secundum or sinus venosus ASD?
RAD with RV conduction delay
Isolated ASD represents what % of all cases of CHD?
10%
An isolated ASD is often diagnosed how?
Mid-childhood with a heart murmur in an asymptomatic child
True or False: It is rare for even a large ASD to present during infancy or early childhood with symptoms of pulmonary overcirculation and poor growth
True
What increases the risk of symptomatic CHF in a child with an ASD?
Associated MV abnormality:
- MR: Primum ASD with cleft MV or MVP
- MS: Lutembacher syndrome
How to adult patients with ASDs present?
- Exercise intolerance
- Atrial arrhythmias
- Pulmonary HTN
Describe normal embryologic development of the atrial septum
- Caudal growth of septum primum from superior common atrium towards endocardial cushion (closes ostium primum)
- Second opening forms in septum primum (ostium secundum)
- Septum secundum (aterosuperior invagination of atrial roof) extends caudally along right atrial side of septum primum (this is gap between septum primum and secundum where foramen ovale sits
What type of closure is needed for primum, sinus venosus and coronary sinus ASDs?
Surgical
Which type of ASD can be closed with transcatheter placement of an ASD occlusion device?
Secundum (unless very large or deficient rims)
AD transmission of secundum ASDs and heart block?
NKX2-5
What should you consider for a patient with an ASD and family history of ASDs?
Screening Holter- If NKX2.5 mutation, possibility for heart block
Primum ASDs are often associated with MR caused by what?
Cleft mitral valve
What is a typical ECG finding in a primum ASD?
Left superior axis deviation
What type of ASD is adjacent to the foramen ovale?
Secundum
What causes a secundum ASD?
- Poor growth of septum secundum
- Excess absorption of septum primum
Secundum ASDs are what % of all ASDs?
75%
What are associated findings with a secundum ASD?
- Usually isolated finding
- Uncommon, but can have PAPVR
- Possible MVP (due abnormal MV configuration due to change in position of ventricular septum with RV volume load)
What ECG findings are seen in secundum ASDs?
RV conduction delay
RAD
What causes a primum ASD?
Septum primum fails to fuse with endocardial cushion
Where is a primum ASD located?
Endocardial cushion
Primum ASDs are what % of all ASDs?
20%
What are associated findings seen with a primum ASD?
Cleft anterior MV leaflet with MR
What is seen on ECG in primum ASD?
Left superior axis deviation, may have 1st degree heart block
Where is a sinus venosus ASD located?
Superior or inferior junction of sinus venosus region and atrial septum
What causes a sinus venosus ASD?
Malposition of the SVC or IVC insertion to the RA
What % of all ASDs are sinus venosus defects?
5% (superior being more common than inferior)
What are associated defects with sinus venosus ASDs?
- Right sided PAPVR
- Overriding SVC or IVC
What is seen on ECG with a sinus venosus defect?
Leftward shift of P-wave axis
Where is a coronary sinus ASD located?
Mouth of the coronary sinus
Coronary sinus ASDs represent what % of all ASDs?
<1%
What are associated defects with a coronary sinus ASD?
Persistent left SVC Mild desaturation (Raghib syndrome- left SVC to unroofed or partially unroofed CS)
What is seen on ECG with an unroofed coronary sinus?
RV conduction delay, RAD
Alagille syndrome is associated with mutations in what pathway?
Notch signaling
Hypoplastic branch PAs?
Alagille
Most cases of Alagille syndrome are caused by mutations in what?
JAG1 (20p12)
*Less commonly mutations in NOTCH2
How is Alagille syndrome inherited?
AD, but variable expression and incomplete penetrance (leads to familial variability in presentation)
Cardiac abnormalities are present in what % of patients with Alagille?
90%
What is the most common cardiothoracic abnormality in Alagille syndrome?
Peripheral pulmonary stenosis (2/3 of patients)
What are other forms of CHD that are seen in Alagille besides peripheral pulmonary stenosis (often seen with peripheral pulmonary stenosis)?
ToF (15% of cases)
-ASD, VSD, CoA, HLHS
What are the non-cardiac features of Alagille?
- Intrahepatic paucity of bile ducts (results in cholestasis with conjugated hyperbilirubinemia)
- Vertebral anomalies
- Renal abnormalities
- Characteristic facial features
- Growth retardation
- Retinopathy
Deletion in chromosome 7 leading to an elastin mutation
Williams syndrome
Supra-aortic valve stenosis + Branch pulmonary artery stenosis?
Williams syndrome
RASopathy associated with mutations in PTPN11 (12q24.1), SOS1, RAF1, RIT1 and other genes?
Noonan
Supra-pulmonary valve stenosis with normal aortic and branch pulmonary arteries?
Noonan
FBN1 mutation on chromosome 15?
Marfan
Dilated aorta, main and branch PAs?
Marfan
What is congenital rubella syndrome associated with?
Peripheral branch pulmonary artery stenosis
What is the most common cardiac abnormality in Alagille syndrome?
Hypoplastic branch pulmonary arteries (2/3 cases)
What causes most cases of Alagille?
Mutations in JAG1 (mutations in NOTCH2 less common cause)
What is the most common extracardiac manifestation in Alagille syndrome?
Paucity of bile ducts
*Cholestasis not expected in neonatal period
ToF absent pulmonary valve is seen in what % of cases of ToF?
2.5%
Large VSD, overriding aorta, rudimentary PV with annular PS, significant PI, markedly enlarged MPA and branch PAs without a PDA?
ToF absent pulmonary valve
What causes the respiratory distress seen in ToF absent pulmonary valve?
Proximal and/or distal bronchial compression by dilated PAs and abnormal pulmonary arteriolar architecture
What is cross sectional imaging with CT or MRI helpful for in ToF absent pulmonary valve?
- Delineate proximal bronchial compression by enlarged PAs
- Delineate distal pulmonary arteriolar branching architecture
- Identify MAPCAs (can also see absent branch PA or aortic origin of a branch PA)
Why might a cath be needed for a patient with ToF absent PV?
To identify a MAPCA providing dual supply to a specific lung segment (usually can see on CT though)
What triggers arrhythmias in CPVT?
Exercise or emotion
What 2 mutations commonly cause CPVT?
RYR2
CASQ2
What is the pathophysiology behind CPVT?
Mutations that lead to diastolic leak of Ca ions from SR resulting in delayed afterdepolarizations and triggered arrhythmias (especially during times of B-adrenergic stimulation)
What is diagnosed by the presence of bidirectional or polymorphic ventricular tachycardia during exercise stress testing in a patient younger than 40 with a structurally normal heart and normal resting ECG (other than sinus bradycardia)?
CPVT
What is the mortality rate of untreated CPVT in children?
50%
What treatment decreases the event rate in CPVT?
B-blockers
What should be started promptly in all symptomatic patients with CPVT?
B-blockers (Class I indication)
Should beta blockers be started in patients with a genetic diagnosis of CPVT without clinical manifestations?
Yes- Class IIa recommendation
What is the beta blocker of choice in CPVT?
Nadolol
What medication can reduce the burden of ventricular arrhythmias in patients with CPVT who have continued exercise-induced ventricular ectopy despite treatment with B-blockers?
Flecainide
True or False: Flecainide or Nadolol can be started as first line treatment for CPVT?
False- Nadolol should be first and then Flecainaide as an adjunct if needed
*Some propose starting both at time of diagnosis
Which patients with CPVT should get an ICD?
- Survivors of cardiac arrest
- Patients who continue to have syncope or exercise-induced bidirectional or polymorphic ventricular tachycardia despite optimal medical management
Why is ICD alone not recommended prior to initiation of beta blockers in CPVT?
Concern for ICD shocks leading to increased sympathetic tone and cycle of increasing arrhythmias
What does CPVT result from?
Mutations in genes related to Ca handling (RYR2 and CASQ2) leading to diastolic leak of Ca from SR triggering DADs and ventricular arrhythmias, especially with B-adrenergic stimulation
How is CPVT diagnosed?
Presence of bidirectional or polymorphic ventricular tachycardia during exercise stress testing in a patient <40 years with a structurally normal heart and normal resting ECG
What is a marker of significant atrial obstruction in a fetus with HLHS?
Equal reversal flow flow with atrial contraction as there is antegrade flow in the pulmonary veins
True or False: A fetus with HLHS and an intact or highly restrictive atrial septum is usually stable in utero?
True
What happens to a fetus immediately after birth with HLHS and intact atrial septum?
Critically ill- pulmonary venous congestion, hypoxia, acidosis (oxygenated blood can’t get out LA into systemic circulation)
True or False: Even with urgent postnatal BAS, infants with HLHS and intact atrial septum have poor outcomes?
True
What is one reason infants with HLHS and intact atrial septum do poorly even with emergent BAS after birth?
They often develop damage to pulmonary vasculature and lung parenchyma due to pulmonary vascular hypertension from lack of LA egress and impediment to pulmonary venous drainage in utero
What % of HLHS cases have a restrictive atrial septum? intact atrial septum?
22
6
True or False: Fetal intervention may be considered for fetuses with established HLHS/IAS?
True (especially if physiology is suggestive of LA hypertension)
What Doppler helps to grade the severity of atrial septal restriction in fetuses with HLHS?
Pulmonary vein Doppler mattern
What does a pulmonary vein Doppler look like for a fetus with HLHS and unrestrictive atrial septum?
Low pulmonary flow that is predominantly antegrade
What finding on pulmonary vein Doppler correlates to the degree of restriction of the atrial septum in fetuses with HLHS?
Flow reversal during atrial contraction (greater prominence of flow reversal, greater restriction)
What antegrade-to-retrograde flow velocity-time integral ratio is suggestive of atrial septal restriction in fetuses with HLHS?
<5 = Element of restriction <3 = More severe obstruction
What is the goal of fetal cardiac intervention with HLHS and a restrictive atrial septum?
- Create an in-utero atrial defect to relieve LA hypertension (septoplasty alone or septoplasty + atrial stent placement0
- This may help to stop or prevent the development of pulmonary vasculopathy, improve O2 at birth and have a more stable transition to post-natal physiology
What are some of the procedural complications involved with an in-utero atrial septoplasty for an infant with HLHS?
Pericardial effusion, fetal bradycardia, need for fetal resuscitative medication, hemothorax, balloon rupture, stent embolization, fetal demise
*Complications in up to 2/3 cases, ideal timing not well defined
What class indication is when there are clear benefits and procedure should be performed?
Class I
What class indication is when benefit exceeds risk and it is reasonable to perform procedure?
Class IIb
What class indication is when there is no benefit any may be harm (procedure shouldn’t be done)?
Class III
What class indication is fetal cardiac intervention to open the atrial septum in cases of HLHs/IAS?
Class IIb (may be considered)
What is one of the most common valvular heart diseases in the US?
MVP
*Can be primary or secondary due to things like Marfan
What are some symptoms associated with MVP?
Palpitations Chest pain Syncope SOB *Often asymptomatic
What can cause MR in MVP?
Prolapse leading to poor coaptation of the leaflets
What causes the single or multiple midsystolic clicks heard in MVP?
Papillary muscle contraction and tensing of the chordal apparatus (in the setting of prolapse of the MV leaflet)
What are the changes in the click and systolic murmur in MVP seen with position changes?
- Due to changes in ventricular loading conditions
- Standing: LVED volume decreased, click moves closer to S1 and increases intensity and duration of systolic murmur
What can happen to the murmur of MVP with progression of disease and worsened MR?
Increase in systolic murmur and may eventually be holosystolic
What is the diagnostic modality of choice with MBP?
Echo
What are the “high points” of the mitral valve?
Area of mitral-aortic continuity and corresponding area posteriorly
What is the best view to define the high points of the mitral valve when assessing for MBP?
PSLA or A3C
What defines the echo diagnosis of MCP?
MV leaflets are displaced more than 2mm above the valve annulus in the PSLA view
*Leaflets often thickened too
What type of MVP is the most common (52%)?
Posterior mitral leaflet prolapse
Rank the types of MVP from most common to least common
- Posterior mitral leaflet prolapse
- Bi-leaflet prolapse
- Anterior mitral leaflet prolapse
True or False: MVP has a benign course in most patients?
True- usually just trivial to mild MR, normal life expectancy
What are some associated complications in MVP?
- Progression to severe MR
- LV dysfunction
- Infective endocarditis
- Atrial arrhythmias
- TIA
- Embolic stroke
- Sudden death
What should be assessed for in all patients with MVP?
Assessment for any signs of a connective tissue disorder
True or False: SBE prophylaxis isn’t indicated for MVP, even with regurgitation?
True
What patients with MVP require antiplatelet therapy or anticoagulation?
Anticoagulation with INR 2-3: Ischemic stroke in presence of atrial thrombus, a-fib or MR
What are indications for surgical repair in MVP?
Symptomatic heart failure with severe MR, LV enlargement or decreased LVEF
True or False; MV repair for MBP has an excellent prognosis?
True
Echo in an infant with dilated LV with severe segmental hypokinesis of LV lateral wall, relatively preserved systolic function of ventricular septum and echogenic papillary muscles/chordal apparatus?
ALCAPA
Bland-White-Garland syndrome?
ALCAPA
ALCAPA represents what % of all congenital cardiac anomalies?
0.5%
What is the proposed theory for embryologic development of ALCAPA?
Abnormal septation of the conus into aorta and PA trunks or anomalous development of the coronary artery buds
Describe coronary perfusion during fetal life and in the early postnatal period in ALCAPA?
Essentially normal- PA and aortic pressures are equal and PA and aortic saturations are similar
What causes problems following birth in ALCAPA?
- PVR falls postnatally
- Perfusion pressure through anomalous LCA decreases along with LCA O2 saturation
- Impaired O2 delivery to LV myocardium
*With time, collateral vessels may arise from RCA to anomalous LCA with flow steal into PA
What is the most common age of diagnosis of ALCAPA?
Infancy (90% cases) at 2-3 months (after PVR falls and they become symptomatic)
In a baby with ALCAPA, what happens after the PVR falls?
- Segmental ischemia of portions of LV most dependent on LCA distribution (lateral LV wall)
- Coronary steal from LV and from RCA through collaterals to PA
What are symptoms seen in ALCAPA?
- Intermittent irritability (due to coronary ischemia- equivalent to anginal chest pain in adult)
- Described as colicky (coronary ischemia at times of exertion, i.e. feeding)
- Heart failure once progresses to infarct (tachypnea, respiratory symptoms, etc.)
What is seen on CXR in ALCAPA?
Cardiomegaly
Sinus tachycardia with q-waves in the lateral leads (I and aVL)?
ALCAPA- Consistent with infarct
Variable ST- and T-wave changes
What lab findings might an infant with ALCAPA have?
Elevated Tn and BNP
3 month old infant with “bronchiolitis” who decompensates quickly?
Think about ALCAPA
What other diagnosis must be differentiated from ALCAPA?
DCM
What is crucial to the echo diagnosis of ALCAPA?
Color Doppler- 2D imaging may be misleading because LCA can course close to the aortic sinus; need color flow to show direction of blood
Besides the abnormal coronary course, what are some other clues to ALCAPA on echo?
- Dilated RCA
- Coronary artery collaterals near aortic root and pulmonary artery
- MR (often have holosystolic apical murmur)
- MR may have eccentric jet/orientation (due to associated papillary muscle ischmia/infarct)
- Echogenic papillary muscles
What additional work may be needed during ALCAPA repair?
Mitral valve repair
Besides echo, what are other imaging modalities which may be required in ALCAPA?
CTA, MRI, coronary angiography
Under what circumstance might you see adult-type ALCAPA?
If there has been sufficient coronary artery collateralization
How does adult-type ALCAPA present?
- Exertional angina
- SOB
- Arrhythmias
- Infarct
- SCD
- Asymptomatic
What is more commonly seen on echo in adult-type ALCAPA?
Marked coronary collateralization
What is the recommendation for adults with ALCAPA?
Surgical revascularization (regardless of status of myocardium)
All Fontan patients are at risk of developing disease in what other organ?
Liver
What increases risk for Fontan-associated liver disease?
- Longer time since Fontan
2. Poor Fontan hemodynamics
What are potential causes for Fontan-associated liver disease?
- Chronically elevated hepatic venous pressures
- Poor hepatic drainage (especially with high Fontan pressure)
- Poor CO and thus poor SpO2 delivery to liver
- Repeat hepatic injury due to multiple bypass runs, low CO syndrome and perioperative ischemia
- Medication side effects
Fontan associated liver disease can lead to what problems?
Cirrhosis
Liver failure
Hepatocellular carcinoma
Early mortality
What should be obtained to monitor for Fontan associated liver disease?
- CBC
- CMP
- Coagulation studies
- Liver/spleen US
*Every 1-3 years
What findings are triggers for referral to a hepatologist with concern for Fontan associated liver dseiase?
- Thrombocytopenia
- Abnormal prothrombin time
- Hypoalbuminemia
- Elevated LFTs
- Elevated direct bilirubin level
- Abnormal liver US results
What should be done to help prevent Fontan associated liver disease?
- Optimize hemodynamics
- Avoid hepatotoxic risks: Obesity, alcohol, certain drugs, vaccination against hepatitis
Fontan patient with mildly abnormal coagulation and thrombocytopenia?
FALD
What findings on liver US are concerning for FALD?
- Abnormal appearing architecture
- Elevated liver shear wave speed
What does liver shear wave speed assess on liver US?
Liver stiffness (marker of fibrosis)
True or False: In FALD, the hepatic echotexture is typically abnormal?
True
Are resistive indices typically reduced or elevated on liver US in FALD?
Elevated
What other type of testing besides US can be done to assess for increased liver stiffness in patients with FALD?
MR elastography
What happens to the LSVC in normal development?
Involutes around 7 weeks of gestation (around same time as development of left innominate vein)
Following involution, what does the remnant of the LSVC become?
Ligament of Marshall
A persistent LSVC occurs in what % of the population?
0.3-0.5%
True or False: Patients with CHD have a higher prevalence of LSVC?
True- Especially ToF, AVCD, Heterotaxy
*Usually duplicate (right SVC too)
In cases of an isolated LSVC, what should you consider?
Dextrocardia or situs inversus
Where does a persistent LSVC typically drain?
CS to RA (>90%)
Embryologically, what vessel forms a common connection between the LSVC and CS?
Left common cardinal vein
Where does deoxygenated blood drain in the setting of an L-SVC to unroofed CS?
LA
What circumstance might a LSVC drain to the roof of the LA?
Heterotaxy
What should be done with concern for a line in an LSVC that wasn’t previously diagnosed?
Echo- confirm LSVC, assess for other structural heart lesions, ensure CS isn’t unroofed
If you have a central line in an undiagnosed LSVC what should be done with regards to line use until an echo is done?
Place a filter on the line until an unroofed CS (and potential for R-L shunting) is ruled out
*Line is otherwise okay to use
If a central line is in a LSVC to intact CS, can you accurately measure CVP from it?
Yes
If an episode of paroxysmal atrial fibrillation is diagnosed with onset <48 hours prior, does a patient require TEE or anticoagulation prior to cardioversion?
No
If an initial shock at 1J/kg doesn’t convert atrial fibrillation, what should be done next?
Second shock with higher energy (2J/kg)
What is the typical starting dose for cardioversion in atrial fibrillation in adults?
120-200J
True or False: An adult sized child with atrial fibrillation could receive cardioversion with a starting dose of 120J
True (can follow adult recommendations)
What position of pad placement is more effective for cardioversion in atrial fibrillation?
Anterior-posterior (as compared to anterior/lateral)
If you have someone who has failed cardioversion x2 (with second shock at higher energy) what can be done next if cardioversion is trialed again?
- Adjust the location of the electrodes (anterior/lateral to anterior/posterior)
- Apply pressure to electrodes
What type of cardioversion should be done for narrow complex or stable tachycardia?
Synchronized
Cardioversion with monophasic or biphasic waveforms requires less energy?
Biphasic requires less energy than monophasic
What is the initial recommended energy dose (biphasic) for cardioversion of atrial fibrillation?
0.5-1J/kg (pediatric)
120-200J (adult)
*Can be increased after a failed cardioversion
What pad placement position is superior for the cardioversion of atrial fibrillation?
Anterior/posterior
True or False: Asynchronous cardioversion can be used in a narrow complex tachycardia?
False- Asynchronous cardioversion should never be used in narrow complex or stable arrhythmias
What 3 things can cause obstruction is subaortic stenosis?
- Discrete membrane (70-80%)
- Fibromuscular ridge
- Tunnel-like long segment narrowing of LVOT
What is the difference between a discrete membrane and fibromuscular ridge with LVOTO?
Discrete membranes are typically more mobile and thinner (1-2mm)
What is tunnel-like subaortic stenosis often associated with?
- Hypoplasia of other left heart structures
- Other types of CHD (DORV, IAA)
- LV hypertrophy
What distance from the aortic valve is a suboartic membrane associated with a greater risk of progression of stenosis and need for future surgery?
<5mm
True or False: A subaortic membrane <5mm is thought to be a risk factor for recurrence after surgical resection?
True
When do most centers consider need for subaortic membrane resection in terms of gradient across the aortic valve?
When it is above 30-40mmHg
*ACHD guidelines recommend repair when mean gradient is >30mmHg or with lower gradient and LV dysfunction, progression of AI, LVH or desire to become pregnant/play competitive sports
AI develops in what % of patients with subaortic stenosis?
70%
What causes AI in subaortic stenosis?
Damage to the valve from the high-velocity jet created by the subaortic stenosis
*Surgery often improves or prevents the progression of AI in most patients
True or False: Patients with moderate or worse AI in the setting of subaortic stenosis are more likely to progress and have a poor result from surgical intervention?
True- Surgery will be further complicated by the need for valve repair
*Many centers advocate repair before AI becomes moderate
Patients with subaortic stenosis and what other factors are most likely to require surgery?
- Tunnel-like obstruction
- Higher estimate pressure gradients
- Moderate or worse AI
- Obstruction close to AoV
Which phosphodiesterase are cAMP specific?
4
7
8
Which phosphodiesterase are cGMP specific?
5
6
9
Which phosphodiesterase are nonselective for cAMP and cGMP?
1 2 3 10 11
How do phosphodiesterase inhibitors work?
- Prevent degradation of cAMP and/or cGMP by acting through second messenger pathways
- Causes increased cardiac contractility, smooth muscle relaxation and reductions in immune/inflammatory cell activity
How do sildenafil and tadalafil work?
Phosphodiesterase 5 inhibitors (prevent degradation of cGMP)
True or False: Phosphodiesterase 5 inhibitors are approved for use in children for pulmonary HTN?
False- do not have FDA approval
What effect does sildenafil or tadafil have?
- Phosphodiesterase 5 inhibitor
- Prevent degradation of cGMP
- In lungs, cGMP is a second messenger to increase production of protein kinase A which ultimately results in vasodilation of the pulmonary vasculature
What is the standard dosing of sildenafil?
0.5-1mg/kg TID or QID
What is the standard dosing of tadalafil?
0.5-1mg/kg daily
What are the common side effects seen with phosphodiesterase 5 inhibitors (sildenafil or tadalafil)?
Headache, myalgia, flushing, nausea, dizziness
*Usually improve with continued use
What are 2 common phosphodiesterase 3 inhibitors?
Amrinone and milrinone
How do phosphodiesterase 3 inhibitors (like milrinone) work?
IV nonselective medications which result in potentiation of cAMP and cGMP
What are the effects of phosphodiesterase 3 inhibitors (like milrinone)?
- Vasodilation of pulmonary vasculature (mediated by cGMP
- Peripheral vasculature vasodilation
- Inotropic effect via potentiation of cAMP (acts as second messenger mediating phosphorylation of protein kinases activating cardiac Ca channels (results in release of Ca from SR)
Which drugs potentiate cGMP, increasing protein kinase A production in the lungs ultimately leading to vasodilation of the pulmonary vasculature?
Sildenafil and tadalafil (phosphodiesterase 5 inhibitors)
What important side effect needs to be monitored for when starting sildenafil or tadalafil?
Hypotension
What happens to the pressure within a fluid as the speed of the fluid increases?
The pressure decreases
The decrease in pressure within a fluid as the speed of the fluid increases creates what?
A vacuum-like effect that can draw in neighboring objects
Venturi effect
What is a concern with a small and restrictive perimembranous VSD?
Potential for prolapse of the right coronary cusp into the defect due to the Venturi effect leading to aortic insufficiency
*Cusp can become elongated and prolapse into the defect with time
True or False: Any patient with a perimembranous VSD and significant or progressive AI should be considered for surgical repair?
True
True or False: Patients with a perimembranous VSD and associated severe AI pre-operatively have poorer long-term outcomes and a greater need for reoperation for valve repair
True
Can a perimembranous VSD with AI be closed in the cath lab?
No- should be closed surgically as device closure could further distort AoV and worsen AI and carries a high risk of heart block
What medications are contraindicated in patients with pre-excitation?
Digoxin
CCB (verapamil)
Why are digoxin and CCB contraindicated in pre-excitation?
- Block conduction at AV node
- Can shorten antegrade effective refractory period of the accessory pathway conduction
- By enhancing conduction via accessory pathway, these drugs can increase risk of a-fib conducting rapidly through the accessory pathway leading to ventricular fibrillation and sudden death
What medications should be avoided in treatment of infants with SVT?
CCB
Why are CCB avoided in infants?
Myocardium particularly susceptible to CCB- can lead to hemodynamic compromise and/or collapse
The risk of AE (perforation of the heart or AV node injury) associated with an EP study/ablation decreases significantly at a patient weight of what?
15-20kg
True or False: An EP study in an infant is possible?
True- But reserved for infants with intractable SVT with hemodynamic compromise despite maximal medical therapy
What helps to determine the position of a transseptal needle and confirm when a sheath can be safely advanced across the atrial septum?
Contrast injection through the transseptal needle
Pulmonary edema/pulmonary hemorrhage in a patient on ECMO is an indication for what?
Decompression of the LA
*Large enough ASD will lower the LA pressure and pulmonary venous pressure reducing risk of pulmonary edema or hemorrhage
How can an ASD be created in a patients with an intact atrial septum who requires decompression of the LA?
- Transseptal puncture
- Radiofrequency wire perforation
- Surgical decompreassion
What are potential complications of a transseptal puncture?
- Pericardial effusion or tamponade
- Aortic root needle puncture
- Right or left atrial wall needle puncture
- Arrhythmias
- Stroke or TIA
- Death
*Overall low complication rates
What happens to the systolic ejection click in patients with pulmonary valve stenosis as it worsens?
- Normal S1 followed by an ejection click
- With progression, click occurs early in systole moving towards and ultimately merging with S1 becoming inaudible in patients with very severe PS
When does pulmonary valve stenosis progress most quickly?
Over first 1-2 years of age (during periods of rapid growth)
Describe findings on a RV angiogram in pulmonary valve stenosis?
- Hypertrophied RV
- Possible dynamic RVOTO
- PV leaflets thick and dome during systole with limited leaflet excursion
- Narrow jet of contrast leaving stenotic orifice of PV
- Jet hits the wall of the MPA resulting in post-stenotic dilation
True or False: In patients with isolated pulmonary valve stenosis, the branch PAs are unobstructed and of normal caliber?
True
What is the treatment of choice for patients with isolated pulmonary valve stenosis?
Transcatheter balloon pulmonary valvuloplasty
What is the treatment of choice for RVOT obstruction due to prominent RV muscle bundles in the infunbidulum?
Surgical resection of the infundibular muscle bundles
What is important to rule out in PA-IVS?
RV-dependent coronary circulation
What are important considerations in PA-IVS?
- Size of RV
- Size of tricuspid valve
- Size of RVOT
- Membranous v. muscular atresia
- Coronary artery involvement
What are treatment options for PA-IVS patients without RV-dependent coronary circulation?
Surgical intervention or perforation of the membranous and atretic pulmonary valve with radiofrequency or stiff end of the wire followed by balloon pulmonary valvuloplasty
