2. Malformations Flashcards
Inheritance of Alagille?
AD
- Liver disease (bile duct paucity)
- Cholestasis
- CHD
- Skeletal abnormalities
- Ocular abnormalities
- Broad forehead, pointed chin
Alagille
What kind of cardiac lesions are seen in Alagille?
Right-sided lesions
- Peripheral PS
- PS
- ToF
*Can see left-sided lesions and septal defects too
Notch ligand
JAG1
Alagille
NOTCH1
AoV pathology
PTPN11
Noonan
Hypertelorism, ptosis, short stature, webbed neck, skeletal anomalies, bleeding diathesis, lymphatic disorders, mental retardation, cryptorchidism, CHD
Noonan
Types of CHD in Noonan
HCM PV stenosis ASD (primum/secundum) VSD ToF PA stenosis CoA Partial AVSD Polyvalvulopathy
TBX1
DiGeorge
Hypocalcemia, immunodeficiency, CHD
DiGeorge
Types of CHD seen in DiGeorge?
IAA-Type B
Truncus
ToF
GATA4
Septation defects
Rubella in 1st trimester increases fetal risk for what CHD?
- PS (valvar, supravalvar, peripheral)
- PDA
*ToF also reported
True or False: Excessive caffeine during pregnancy increases risk for CHD
False
CHD associated with maternal PKU?
- Left-sided defects
- Septal defects
- ToF
- Microcephaly
- Mental retardation
- High phenylalanine
PKU
7q11.23 deletion
Williams
Hypercalcemia, skeletal and renal anomalies, cognitive deficits, social, “elfin” facies
Williams
Types of CHD seen in Williams?
- Supravalvar AS
2. Supravalvar PS
3/6 SEM, friendly, stellate irises, long philtrum, depressed nasal bridge, prominent lower lip, enamel hypoplasia
Williams
How is the deletion associated with Williams detected?
FISH (not by routine karyotype)
*7q11.23 deletion
In Williams, does the supravalvar PS or AS tend to improve with time?
PS improves with time
AS usually progresses
True or False: SCD has been described in Williams
True
*Suspected causes include coronary artery stenosis and severe biventricular outflow tract obstruction (myocardial ischemia, decreased CO, arrhythmia)
Why are patients with William’s syndrome prone to develop HTN?
Renal artery stenosis
Growth retardation, short palpebral fissures, small mouth, micrognathia, prominent occiput, short sternum, small nipples, clenched hands, disorganized/hypoplastic palmar creases, hyperconvex nails, rocker bottom feet
T18
What is the % incidence of CHD in T18?
> 90%
Most common CHD in T18?
- Perimembranous VSD
- ToF
- DORV
- Polyvalvular dysplasia
What % of children with T18 die within 1st year of life?
90%
*Usually not from heart disease
Most common CHD associated with 22q11 deletion?
- ToF
- IAA Type B
- Truncus
- Perimembranous VSD
- Aortic arch anomalies
*Wide range however that can include PS, ASD, heterotaxy, HLHS
What can develop is a large ASD is left unrepaired?
Severe irreversible pulmonary HTN
In which gender is there a higher preponderance for the development of pulmonary HTN from an unrepaired ASD?
Female
Above what diameter ASD is spontaneous closure rare?
> 8mm
What may need to be done prior to repair of any type of ASD that is not discovered until adolescence or adulthood?
Cath to assess for pulmonary HTN and vasoreactivity
Sinus venosus ASDs
- 5-10% of ASDs
- Posterior/Superior to fossa ovalis
- Commonly associated with anomalous connection of R pulmonary veins to either RA or SVC near caval-atrial junction
What is seen on ECG for a sinus venosus ASD?
Frontal plane P-wave axis <30 degrees (up to 1/2 patients)
Which types of ASDs have a normal P-wave axis?
- Secundum
- Primum
- PFO
- Unroofed CS
*Sinus venosus ASDs can have
In which defect are the papillary muscles closer together with the anterior muscle being closer to septum than normal and posterior muscle being further from the septum than normal?
Complete AV canal defect
How many leaflets does a common AV valve have?
5
*Beneath 5 commissures are 5 papillary muscles
In a complete AVCD are the left sided papillary muscles closer together or further apart as compared to a normal heart?
Closer
Which AV valve leaflet is smaller than normal in a complete AVCD?
The left lateral
How are the left sided papillary muscles in a complete AVCD rotated and what effect does this have on their position?
Counterclockwise
- Posterior further from septum
- Anterior closer to septum
What is the potential result of the change in left sided papillary muscle arrangement in complete AVCD?
Progressive LVOT obstruction
also the large anterolateral muscle bundle
Components of a partial AVSD?
- Primum ASD
2. Cleft anterior MV leaflet
True or False: A primum ASD results in earlier and more severe symptoms as compared to a secundum ASD
True
What is the most common reason for reoperation in partial AVSD?
Repair of recurrent or residual MR/MS
What do you need to think about in a patient with AVSD and a SEM?
LVOTO
Progressive LVOT obstruction is more common in patients with what type of AVSD?
Partial- 2 AV valve orifices
What is different about the aortic valve in AVSD?
Displaced anteriorly (versus being wedged between mitral/tricuspid annuli)
- Creates elongated/gooseneck deformity of LVOT
- LVOT obstruction can happen in any form of AVSD
Is LVOTO more common in AVSD with a common AV valve or 2 AV valve orifices?
Common
What % of patients with AVSD require reoperation for LVOTO?
10%
List mechanisms for progressive LVOTO in AVSD?
- Attachments of superior bridging leaflet into ventricular septum
- Extension of anterolateral papillary muscle into LVOT
- Discrete fibrous subaortic stenosis
- Tissue from aneurysm of membranous septum bowing into LVOT
Post-op from ASD/VSD repair hearing widely split S2 and no murmur… what is the cause?
RBBB
True or False: Prominent splitting of S2 can be heard with a small VSD
True
-Usually normal, but can have this sometimes
What should you consider in a VSD when you have systolic murmur that transmits to the LUSB or Apex?
LUSB: PS
Apex: MR
What limits flow across a large/unrestrictive VSD?
Relative resistances of systemic/pulmonary circulations
What anomalies of the tricuspid valve can be seen in a perimembranous VSD with L-R shunting?
Redundant septal leaflet tissue (this can partially or completely occlude the defect)
What happens to LV mass and volume after a VSD repair?
Decrease
Volume decreases at a greater rate than mass
Patients who develop Eisenmenger physiology begin manifesting cyanosis before what age?
2
What can happen to the aortic valve with an unrepaired outlet or perimembranous VSD?
Prolapse of one of the aortic cusps
-Leaflet partially closes the VSD and eliminates shunting, but the AI is progressive
What can be seen in an unrepaired outlet VSD?
- Deficiency of muscular/fibrous supports below the AoV with herniation of the right coronary leaflet through the VSD
- Aortic commissures are usually normal
- Results in aortic insufficiency
What can be seen in an unrepaired perimembranous VSD?
- Herniation of the right (or less commonly non) coronary cusp
- Frequent abnormalities of aortic commissures (usually right/non)
- Results in aortic insufficiency
- May have associated infundibular PS
Relationship of the bundle of His to an inlet VSD?
Bundle passes anterior-superior to defect
Relationship of perimembranous VSD to bundle of His?
Bundle of His is subendocarial and courses along the posterior-inferior margin of the defect
Where is the conduction tissue in relation to a muscular or outlet VSD?
Usually far removed unless the defect extends into the perimembranous area.
NEC + PDA
Surgical closure of PDA
Potential complication of unrepaired PDA?
Endarteritis or endocarditis
*PDA can account for up to 15% of all endocarditis cases
Most common organisms for endocarditis with PDA?
S. Viridans
S. Aureus
Where are vegetations most commonly seen in a PDA?
PA end of the duct
Which event is most responsible for early, functional closure of ductus arteriosus?
Medial smooth muscle cell migration in the wall of the ductus
When do the 2 phases of post-natal closure of the PDA occur?
1st: Within 12 hours after birth
2nd: 2-3 weeks
Describe the 2 phases of post-natal closure of the PDA
- 1st: Contraction and cellular migration of the medial smooth muscle in the wall of the ductus arteriosus that causes the vessel walls to become thick and protrude into the vessel lumen
- 2nd: Infolding of the endothelium, disruption and fragmentation of the internal elastic lamina, proliferation of the subintimal layers, and hemorrhage and necrosis in the subintimal region. There is connective tissue formation and replacement of muscle fibers with fibrosis with subsequent permanent sealing of the lumen… forms the ligamentum arteriosum
Theoretical benefits of ibuprofen over indomethacin for closure of PDA in a premature infant?
- Similar rates of ductal closure
- Fewer negative effects on renal function, cerebral vasculature and cerebral blood flow
Which has higher risk of intraventricular hemorrhage in PDA closure… indomethacin or ibuprofen?
Equivocal
What is the use of ibuprofen as prophylaxis for PDA closure associated with an increased risk of?
Pulmonary HTN
What is the standard surgical approach for ALCAPA?
Direct reimplantation of the origin of the LCA into the aorta
What is an alternative approach for repair of ALCAPA?
Takeuchi
-AP window created and a tunnel created that directs blood from aorta to left coronary ostium
What is a risk factor for mortality and late reoperation in ALCAPA?
Mitral insufficiency
*Due to papillary muscle infarction and dysfunction
What determines specific features in a sinus of Valsalva fistula from the aorta to the RA?
Site of entry to heart
*Localized weakness in wall of sinus of Valsalva causes aneurysmal bulging… if this ruptures, size of fistula determines how large shunt will be
What type of shunting results from a sinus of Valsalva fistula emptying into the left heart v. right?
Right: Right to left shunt
Left: No shunt (O2 blood back to LV)
Describe the murmur in a small sinus of Valsalva fistula
- Continuous murmur
- Maximal intensity in the 3rd or 4th intercostal space near the sternal edge
- If fistula enters RA, murmur may be maximal to right of sternum
Describe exam findings in a large sinus of Valsalva fistula
- Wide pulse pressure
- Collapsing pulse
- LVH
- If fistula enters right side, there will be RV hyperactivity
- If fistula enters LV, may have a to-and-fro murmur and simulate aortic incompetence
- Occasionally, there is only a diastolic murmur in fistulae entering the LV (or the high pressure RV in neonate)
Which sinus does the coronary in ALCAPA usually arise from?
Left posterior facing sinus on PA
Describe pathophysiology in ALCAPA
- In fetal life, pressures and oxygen saturations are similar in the aorta and pulmonary artery so myocardial perfusion is normal
- After birth, PAs have low pressures and desaturated blood so myocardial perfusion is compromised
- Myocardial ischemia subsequently occurs and this is worsened with exertion in feeding or crying
- As time passes, infarction of the anterolateral LV free wall occurs. Mital valve papillary muscles are affected and MR develops
True or False: Anomalous coronary artery origins from the wrong sinus of Valsalva are generally asymptomatic in infancy?
True
What is the most common coronary artery anomaly?
Origin of left circumflex from right main (1/3 of all major coronary arterial anomalies)
True or False: A left circumflex from the right coronary artery has no general clinical significance in the absence of intracardiac surgery
True
Why is an origin of LCA from the right sinus of Valsalva important clinically?
- If passes between aorta and RVOT, risk for sudden death during or just after vigorous exercise
- Many cases, ostium of the LCA is slit-like… increases risk further
What is often seen with aneurysms in the sinus of Valsalva?
VSD (50% of the time)
*Especially right sinus aneurysms associated with defects of the outlet septum
What causes an aneurysm of the sinus of Valsalva?
- Localized weakness of the wall leads to aneurysmal bulging
- Localized aneurysms are usually congenital with thinning just above the annulus at the leaflet hinge
- Can follow IE
Which gender is more affected by aneurysm of the sinus of Valsalva?
Male (75%)
Where are sinus of Valsalva aneurysms more frequently located?
- 65% located in right aortic sinus
- 25% in non-coronary sinus
- 10% in left aortic sinus
What circumstance is most common for rupture of sinus of Valsalva aneurysm?
-Rupture of right sinus into RV in setting of an outlet VSD
- Can rupture into any chamber
- Rupture into pericardium is rare
What is risk of mortality in 1st week of like with cerebral AVM causing high-output cardiac failure?
90%
*From intractable CHF or neurologic complications (seizures, intracranial hemorrhage)
Central nervous system AVMs manifest symptoms according to what?
Hemodynamic effect
What are the most common cerebral AVMs to present with CHF?
- Deep (vein of Galen)
- Superficial (pial)
- Dural
What is seen in infants with significant cerebral AVMs?
- High-output CHF
2. Dilation of all cardiac chambers, feeding arteries and draining veins
What happens if there is venous obstruction in a cerebral AVM?
Flow can be restricted… patient may present with venous HTN or cerebral ischemia
If an infant with a significant cerebral AVM survives, what are long-term problems?
Neurologic morbidity- Hydrocephalus, mental retardation, hemorrhage
If you have multiple pulmonary AVMs, there is a >80% of having what?
HHT
- Most pulmonary AVMs are congenital or associated with HHT
- Overall 30-50% of patients with pulmonary AVMs have HHT
What happens to pulmonary AVMs as a child grows?
Enlarge
What type of AVMs have increased CO?
Systemic
What happens to pulmonary blood flow and pressures with a pulmonary AVM?
Unchanged
*PVR normal, resistance within AVM is low, resistance in other lung segments may be elevated
What is the treatment of choice for a pulmonary AVM?
Transcatheter embolization
- Goal is to raise systemic arterial oxygen tension by occluding most significant afferent arteries (>3mm diameter)
- Improves hypoxia, resolves orthodexia
- Minimal growth of small remaining AVMs
Embolization of pulmonary AVMs prevents what?
- Stroke
- Tia
*DOES NOT reduce risk of brain abscesses
What is done to avoid device embolization when closing a pulmonary AVM?
-Using a coil or umbrella versus liquid adhesive or beads
What measurement has best potential to distinguish a large AVM from a large PDA in a young infant?
Systemic vein oxygen saturation during cath
In what ways are large AVMs and large PDAs similar?
- Hemodynamic effects (large extracardica L-R shunts)
2. Same changes in pulse pressure, liver span, CT ratio on CXR and QRS axis on ECG
What does a cath for a large AVM show?
- High CO
- Elevated atrial and ventricular end-diastolic pressures
- Widened systemic arterial pulse pressure
- Large difference in the oxygen saturation between the SVC and IVC (higher sat from involved area)
Barium esophagram with anterior indentation?
- Pulmonary artery sling
- Tumor
Describe the anatomy in a pulmonary sling
- Origin of LPA from RPA
- LPA arises as a very proximal branch of the RPA and loops around the trachea
- Only situation in which a major vascular structure passes between the tracheal and esophagus
- Rare
- Usually isolated abnormality, but can be associated with other CHD (ToF)
What tracheal anomaly is a pulmonary sling frequently associated with?
-Complete cartilaginous rings in the distal trachea resulting in tracheal stenosis
Describe a right aortic arch with mirror image branching
- Traverses right mainstem bronchus
- 1st branch left innominate (divides into left carotid and left subclavian
- 2nd branch is right carotid
- 3rd branch is right subclavian
- Duct usually on left and arises from base of innominate artery
- Doesn’t typically form a vascular ring
What should be done if a right aortic arch is noted CT imaging?
- Echo to assess for CHD
- Commonly associated with ToF, but also other conotruncal abnormalities (DORV, etc.)
True or False: A right aortic arch with retroesophageal innominate artery, left PDA results in a vascular ring?
True
What is a vascular ring?
Aortic arch anomaly in which trachea and esophagus are completely surrounded by vascular structures
Symptoms of a vascular ring?
- Respiratory: Stridor, PNA, bronchitis, cough, neck hyperextension
- Swallowing difficulty (less common, usually toddlers or older children)
Absent limb pulses in all extremities, but strong carotid pulses bilaterally?
IAA type B + Anomalous subclavian
Describe the anatomy of type A, B, C IAA
IAA = Complete separation of ascending and descending aorta A = Interruption distal to left subclavian B = Interruption between carotid and subclavian C = Between carotid arteries
How to differentiate critical AS v. IAA type B + Anomalous subclavian?
- IAA type B + Anomalous subclavian will have strong carotid pulses
- Critical AS will have all weak pulses
What is the most common vascular ring?
Double aortic arch
What is the second most common vascular ring?
Right arch with diverticulum of Kommerell
True or False: A right aortic arch with mirror image branching usually causes no ring
True
*Unless there is a left duct
What is the most common aortic arch abnormality?
Left arch with retroesophageal right subclavian
*Doesn’t form a ring and usually asymptomatic
True or False: Right aortic arch with retroesophageal innominate artery doesn’t create a vascular ring
False
- Very rare
- Ductus completes vascular ring (connects LPA with base of innominate)
Describe cor triatriatum
- Membrane separates more proximal chamber which receives the pulmonary veins from the more distal LA which communicates with the mitral valve
- Typically a hole in the membrane ranging from <3mm to 1cm
- Distal (true) LA is in continuity with the LAA
- Fossa ovalis is usually between the distal LA and RA
- Occasionally, a PFO/ASD in present in this area
- RVH and RV dilation are almost invariably found
- RAH and dilation are present in < 25% of cases
- Hypertrophy and dilation of RA results in tall, broad and oftentimes peaked P waves on ECG
What 2 things is prognosis in TAPVC influenced by?
- Size of interatrial communication
- Degree of obstruction in anomalous venous pathways
What is the long-term prognosis in TAPVC dependent on?
- State of pulmonary vascular bed at time of surgery
- Patency of pulmonary venous-LA anastomosis
*Overall mortality for unrepaired 80% + at one year
What arrythmias are most common to develop in repaired TAPVC?
Atrial: Sinus bradycardia, atrial flutter, SVT
*Ventricular arrhythmias unusual
Describe Scimitar syndrome
- Anomalous connection of the right pulmonary veins to the IVC
- Creates a crescent-like shadow in the right lower lung field which resembles a Turkish sword (Scimitar)
What are frequent coexistent anomalies in Scimitar?
- Hypoplasia of right lung/chest
- Mesocardia or dextrocardia
- Lung parenchymal abnormalities
What causes a superior sinus venosus ASD?
Deficiency of the common wall of the SVC and pulmonary vein (RUPV)
- Defct “unroofs” the RUPV
- Unroofed pulmonary vein drains into the SVC and LA orifice becomes an interatrial communication (isn’t actually a defect of atrial septum)
What should be done for infradiaphragmatic TAPVC?
Surgery ASAP
- If sick, optimize as able
- In past BAS was used as palliation, but just delays definitive procedure and not recommended
- Balloon dilation of obstructed venous channel not typically successful
What is the most common site of obstruction in infradiaphragmatic TAPVC?
-Anomalous vessels’ connection with portal vein or hepatic veins
If unobstructed, what does flow look like in the anomalous vessel in infradiaphragmatic TAPVC?
- Low-velocity, phasic laminar flow pattern with brief flow reversal during atrial systole
- Luminal narrowing is associated with flow acceleration and turbulence by color Doppler
When do symptoms from cor triatriatum present?
Usually in 1st few years of life, but some can present in 2-3rd decade of life
What are common late presenting symptoms of cor triatriatum?
- Dyspnea
- Frequent respiratory issues (asthma)
- PNA
*Usually thought to have primary pulmonary disease
Untreated cor triatiatum results in what?
Pulmonary HTN
Exam findings of cor triatriatum?
- Loud pulmonary component of 2nd heart sound
- RV heave
- Pulmonary systolic ejection click
- TR murmur can be present
- Less often, a diastolic murmur is detected at the mitral area or a continuous murmur can be heard
- Right heart failure common
- Rales heard if pulmonary edema present
True or False: Patients with pulmonary edema or right heart failure due to cor triatiatum often have progressive disease despite maximal medical management
True
What should be done for someone with cor triatriatum and pulmonary edema or right heart failure?
Surgery ASAP
*Resection of membrane under bypass
How long is survival with cor triatriatum with pulmonary edema and right heart failure if untreated?
Months
*If survive operative correction, severe PA changes which cause pulmonary HTN can regress… for these patients, prognosis is excellent
What is an interrupted IVC?
Absence of the hepatic segment of the IVC with azygous continuation to the right or left SVC
What is a factor that could cause hypoxia in a patient with interrupted IVC with azygous continuation and bilateral Glenn shunts years following surgrey?
Pulmonary AVMs
*Can develop after Glenn due to exclusion of hepatic factor to the lungs (may be 1 or both lungs pending on preferential blood flow)
What does a vertical vein represent?
A persistent embryologic connection between the splanchnic plexus of the lung buds and the cardinal veins
Besides PAPVR to the right SVC (sinus venosus defect) and RA (malposition of the septum primum) what is the most common type of PAPVC?
Left pulmonary veins to the left innominate vein
What is the name of the vein that connects the left sided pulmonary veins to the left innominate vein in PAPVR?
Vertical vein
Where anatomically is a vertical vein compared to a L-SVC?
Vertical vein usually more posterior than L-SVC (which is immediately behind the LAA)
If the left pulmonary veins drain to the L-SVC, what should the L-SVC drain to?
Still CS or LA
What type of ASD is common with PAPVC to the left innominate vein?
Secundum
*Primum uncommon and rarely is septum intact
Congenital malformations of the CS are frequently associated with what?
Arrhythmias
What is reported in a significant % of patients with diverticular of the CS?
SVT and SCD
What causes SVT in a patient with diverticulum of the CS?
Accessory pathway that traverses the diverticulum to form an AV connection
2 week old with tricuspid atresia, d-TGA, moderately restrictive VSD, moderately hypoplastic arch, acidotic… best surgical approach?
DKS with arch augmentation and BTT shunt
Are ventricular endocardial potentials recorded past the expected anatomic tricuspid valve annulus during EP assessment more specific for Uhl or Ebstein?
Uhl
What is a congenital cardiac malformation that consists of an almost total absence of the RV myocardium?
Uhl
Physical exam consistent with Uhl?
- Cyanosis
- Hepatosplenomegaly
- JVD
- Quiet precordium
- Diminished peripheral pulses
- Decreased heart tones
- Pansystolic TR murmur (also can be no murmur or non-specific murmur)
What is seen on ECG in Uhl’s?
- Prominent P waves
- Diminished QRS amplitude (especially in the right precordial leads)
What is seen on CXR in Uhl’s?
- Cardiomegaly
- Normal to diminished pulmonary vascularity
*Similar to Ebstein
What is seen on Echo in Uhl’s?
Marked right sided dilation
Describe the PA, RA, RV pressure waveforms in Uhl’s
Similar to each other
What is dominant in the RA waveform in Uhl’s?
A-wave
What is seen on endocardial potentials in Uhl’s?
Normal transition between the ventricular and atrial complexes
*This helps rule out Ebsteins
True or False: Many patients with Uhl’s anomaly die in infancy or childhood?
True
Markedly dilated, “parchment-like” RV with thickened endocardium, few if any true myocardial cells in the RV free wall, tricuspid valve arises normally from dilated valve annulus and might be dysplastic (but not displaced into RV cavity)
Uhl’s Anomaly
True or False: With normal CO, the severity of PS is based on measurements of RV pressure and valve gradient?
True
What constitutes mild PS?
RV pressure < LV pressure or
Peak valve gradient <35-40mmHg
What constitutes moderate PS?
RV pressure 50-75% of LV pressure or
Peak valve gradient 40-60mmHg