cardio Flashcards
perinatal and neonatal circulation
-clamping of umbilical cord:
-Eliminates low pressure system of the placenta and increases systemic blood pressure
-Decreased venous return from placenta and decreases right atrial pressure
-breathing begins:
-Air replaces lung fluid
Pulmonary resistance decreases, increases blood flow to lungs, increases pulmonary venous return to LA – LA pressure > RA pressure = closure of foramen ovale!!
Arterial oxygen tension increases = ductus arteriosus begins to constrict
functional murmurs
congenital heart disease
-MC congenital disorder in newborns (8 in 1,000 births)
-25% of CHD have critical CHD requiring surgical or catheter-based intervention w/i 1st year of life
-divided into 3 groups:
-Left-to-right shunts (Acyanotic)
-Right-to-left shunts (Cyanotic)
-Obstructive, stenotic lesions
acyanotic CHD: ventricular septal defect
-MC
-Small VSD: Often asymptomatic; high-frequency, loud murmur
-Moderate-large VSD result in pulmonary over circulation and HF
-Auscultation: Pansystolic murmur at LLSB
-Large shunts increase flow over mitral valve causing a mid-diastolic murmur at apex
-Splitting of S2 and intensity of P2 depend on PA pressure
-Imaging
-ECG: Larger VSDs with possible findings of LAE/LVH
-CXR: Cardiomegaly, enlargement of LV, increase in PA silhouette, increased pulmonary blood flow
-PHTN > RV enlargement/hypertrophy
-Echo: Location/size of defect + hemodynamic information (magnitude of shunt and R/PA pressure)
-Tx:
-1/3rd of VSDs close spontaneously
-Small VSDs: Close spontaneously; if not, surgical closure
-Initial for moderate-severe: Diuretics + digoxin/afterload reducers; continued poor growth/PHTN requires surgical closure (closure device)
acyanotic CHD: atrial septal defect (ASD)
-Rarely symptomatic, even if large
-Prominent RV impulse at lower L sternal border palpable
-Auscultation: Soft (grade I/II) systolic ejection murmur in region of RV outflow tract and a fixed split S2 (due to overload of RV with prolonged ejection into pulmonary circuit)
-Larger shunt: Mid-diastolic murmur at LLSB resulting from increased volume passing across tricuspid valve
-Imaging
-ECG may show RAD and RV enlargement
-CXR may show cardiomegaly, RAE, prominent pulmonary artery
-Echo for location/size and magnitude of shunt
-Tx: Significant shunt still at 3 years > closure (cath lab – closure device)
acyanotic CHD: patent ductus arteriosus
-Small PDAs asymptomatic; moderate-large shunts produce signs of HF
-Physical findings: Widened pulse pressure
-Auscultation: Continuous, machine-like murmur at L infraclavicular area, radiating along pulmonary arteries
-Larger shunts: Increased flow across mitral valve > mid-diastolic murmur at apex and hyperdynamic precordium
-Splitting of S2/intensity of P2 depend on PA pressure
-Imaging
-ECG may show LVH; RVH if PHTN present
-CXR with full pulmonary artery silhouette and increased pulmonary vascularity
-Echo for size/anatomy of PDA and magnitude of shunt and PA pressure
-Tx:
-Moderate-large/symptomatic: Indomethacin!!!!!!, diuretics, eventual closure (cath lab with coil embolization or PDA closure device)
acyanotic CHD: endocardial cushion/AV septal defect
-May be complete, partial, or transitional
-Complete: ASD, posterior/inlet VSD, common AV valve
-Partial/transitional: 2, separate AV valves
-May have AV valve insufficiency at either level
-common with downs syndrome
-Sx of HF by 6-8 wks of life (decreased PVR)
-PHTN present due to increased pulmonary blood flow, and pulmonary vascular obstructive disease may develop early
-Murmurs vary depending on degree of shunting at atrial/ventricular levels
-Imaging
-ECG: LAD and combined atrial enlargement/ventricular hypertrophy
-CXR: Cardiomegaly with enlargement of all chambers and presence of increased vascularity
-Echo is dx
cyanotic CHD: tetralogy of fallot
-MC cyanotic
-Characterized by 4 structural defects:
-1. Ventricular septal defect
-2. Overriding aorta (over VSD)
-3. Pulmonary stenosis
-4. Right ventricular hypertrophy
-Pulmonary stenosis murmur usual initial abnormal finding
-As pulmonary stenosis worsens, R-L shunting increases
-Single S2 and right ventricular impulse at L sternal border
-Hypoxic/Tet spells
-Infant: Restless, agitated, inconsolable crying
-Toddler: Squatting -> increase venous return
-Hyperpnea with gradually increasing cyanosis
-blue mucous membranes -> BAD
-Severe spells: Prolonged unconsciousness and convulsions, hemiparesis, or death
tetralogy of fallot imaging and tx
-Imaging:
-ECG: RAD, RVH
-CXR: Boot-shaped heart (small main pulmonary artery and upturned apex from RVH)
-Echo: Anatomy of pulmonary stenosis, coronary anomalies
-Treatment
-Progressive pulmonary stenosis/cyanosis
-Hypoxic spells: Oxygen, knee-chest position, ketamine/phenylephrine (increased SVR)
-Indication for surgical repair
-Complete surgical repair with VSD closure and removal/patching of pulmonary stenosis
cyanotic CHD: transposition of the great arteries
-Cyanosis, tachypnea, single S2
-Imaging
-ECG: RAD/RVH
-CXR: Increased pulmonary vascularity, “egg on a string” cardiac shadow (narrow superior mediastinum)
-Echocardiography: Demonstrates the transposition, sites/amounts of mixing, associated lesions
-Treatment
-Prostaglandin E1 to maintain ductal patency/relax pulmonary vasculature
-Balloon atrial septostomy
-Arterial switch (complete surgical repair)
cyanotic CHD: tricuspid atresia
-Severely cyanotic, single S2
-Imaging
-ECG: LVH
-CXR: Normal/slightly enlarged cardiac silhouette with decreased pulmonary blood flow
-Echocardiography: Anatomy, lesions, source of pulmonary blood flow
-Treatment:
-Prostaglandin E1 (maintains pulmonary blood flow until surgery)
-Surgery in stages: (dont need to know)
-Blalock-Taussig procedure: Subclavian artery-to-pulmonary shunt
-Glenn procedure: SVC to PA anastomosis with takedown of initial shunt at 4-6 months
-Fontan procedure: Redirection of IVC and SVC to PA when child is approximately 15 kg
cyanotic CHD: truncus arteriosus
-Development of HF as pulmonary vascular resistance decreases
-Tachypnea, difficulty feeding, poor growth
-Bounding peripheral pulses
-Auscultation: Possible systolic murmur with click at L sternal border, single S2 (single valve)
-Imaging
-ECG/CXR: Combined ventricular hypertrophy, cardiomegaly, increased pulmonary vasculature
-Echocardiography: Anatomy, truncal valve function, and origin of PAs
-Treatment
-Medical management: Anti-congestive medications
-Surgical repair: VSD closure with placement of conduit between RV and PAs
cyanotic CHD: total anomalous pulmonary venous return
-Most important determinant is presence or absence of obstruction to pulmonary venous drainage
-Absence of obstruction:
-Minimal cyanosis/asymptomatic
-Hyperactive RV impulse, widely split S2 (increased RV volume) and a systolic ejection murmur at LUSB
-Mid-diastolic murmur at LLSB from increased flow across the tricuspid valve
-Presence of obstruction:
-Cyanosis, marked dyspnea/tachypnea, and signs of R sided HF
Cyanotic CHD: Total Anomalous Pulmonary Venous Return dx and tx
-Imaging:
-Absence of obstruction:
-ECG: RV overload
-CXR: Cardiomegaly with increased pulmonary blood flow
-Presence of obstruction
-ECG: RAD/RVH (from increased pulmonary congestion)
-CXR: Heart normal/mildly enlarged with varying degrees of pulmonary edema
-Echo: Extent of volume overloaded R side of heart, R-L atrial level shunting, and common pulmonary vein site of drainage/degree of obstruction
-Treatment
-Surgery: Common pulmonary vein opened into the LA, ligation of any vein/channel that had been draining the common vein
Cyanotic CHD: Hypoplastic Left Heart Syndrome
-Ductus arteriosus constriction > signs/symptoms of HF from excessive pulmonary blood flow/obstruction of systemic blood flow
-Diffusely weak/absent pulses, usually no heart murmur, S2 single/loud
-Low CO > grayish color to cool, mottled skin
-Imaging
-ECG: RVH with decreased LV forces
-CXR: Cardiomegaly (R-sided enlargement) and pulmonary venous congestion/edema
-Echocardiography: Small left side of heart, degree of mitral/aortic valve stenosis, hypoplastic ascending aorta, adequacy of L-R atrial flow and R-L ductal flow
-Treatment
-Medical: PGE1, correction of acidosis, BP support as needed
-Surgery is staged (newborn, 4-6 months, 2-3 years): Procedures create a systemic source for pulmonary circulation, leaving RV to supply systemic circulation
-Heart transplant for failed surgical palliation or if systemic RV fails (adolescence/young adulthood)
obstructive CHD: pulmonary stenosis
-Moderate-severe stenosis: Exertional dyspnea, easy fatiguability
-Auscultation: Systolic ejection murmur at second, left intercostal space, radiates to back
-Click that varies with respiration
-More severe stenosis: Impulse at LLSB from RVH
-Imaging
-ECG: RAD and RVH
-CXR: Dilation of main pulmonary artery
-Echo: Site of stenosis, degree of hypertrophy, valve morphology, pressure gradient estimate
-Treatment
-Balloon valvuloplasty, surgery if unsuccessful
obstructive CHD: aortic stenosis
-Severe: Easy fatigability, exertional chest pain, and syncope
-Auscultation: Systolic ejection murmur at second, R intercostal space, radiating into the neck
-Click if valve is involved
-Imaging
-ECG: LVH
-CXR: LVH, dilation of ascending aorta/aortic knob
-Echocardiography: Site of stenosis, degree of hypertrophy, valve morphology, pressure gradient estimate
-Treatment/Prognosis
-Degree of stenosis frequently progresses with growth/age
-Aortic insufficiency often develops/progresses
-Serial follow-up with echocardiography is indicated
-Balloon valvuloplasty, surgery if unsuccessful
obstructive CHD: coarctation of the aorta: clinical manifestation
-Infants:
-Hypoplastic aortic arch, abnormal aortic valves, and VSDs
-Symptoms develop when ductus closes (2 weeks of age)
-Poor feeding, respiratory distress, and shock possibly sooner
-Femoral pulses are weaker and delayed compared with the R radial pulse; BP in LE < UE
-Older children:
-Leg discomfort with exercise, headache, epistaxis
-Decreased/absent LE pulses, HTN of UE
-Auscultation: L interscapular area of back, continuous (if collateral vessels have formed)
-Systolic ejection murmur with click if abnormal aortic valve (50% of time) is present
obstructive CHD: coarctation of the aorta: imaging and tx
-Imaging
-Infants:
-ECG/CXR: RVE/H with marked cardiomegaly and pulmonary edema
-Older children
-ECG/CXR: LVH and mildly enlarged heart; rib notching (from collateral vessels)
-Echo: Site/degree of coarctation, presence of LVH, aortic valve morphology/function
-Tx:
-Infant with cardiac decompensation: IV prostaglandin (chemically opens ductus – closure would otherwise worsen coarctation), inotropic agents, diuretics, supportive care
-Balloon angioplasty < surgical repair
rheumatic fever/heart disease
-Overall incidence in U.S. < 1/100K, peak age of risk is 5-15 years (U.S.)
-MC in girls and African Americans
-Group A B-hemolytic streptococcal infection of upper respiratory tract is trigger in predisposed individuals (typically with immune response genes)
rheumatic fever: jones criteria
Jones Criteria! – Two major criteria or one major and two minor manifestations PLUS evidence of streptococcal infection
rheumatic fever: sx
-Carditis
-Pancardiac inflammation; may be limited to valves, myocardium, or pericardium
-Mitral valve MC affected, with insufficiency and residual defect
-Aortic valve second MC affected (> M, African Americans)
-Early decrescendo diastolic murmur consistent with aortic insufficiency
-Polyarthritis (80% of patients)
-Large joints MC involved, typically migratory
-Joint swelling/limitation of movement
-Sydenham Chorea
-Involuntary and purposeless movements, emotional lability
-Progressively worse > ataxia/slurring of speech
-Muscular weakness following onset of initial symptoms
-May last up to 3 months, may not be apparent for months to years after acute episode of rheumatic fever
-Erythema Marginatum: Macular, serpiginous, erythematous rash with sharply demarcated border on trunk/extremities
-Subcutaneous Nodules (severe cases)
-Occur over joints, scalp, and spinal column
-Few mm – 2 cm in diameter, nontender, free mobile
rheumatic fever: tx
-Acute Treatment
-Anti-Infective Therapy
-Benzathine PCN: Single IM injection (0.6-1.2 million U effective)
-Alternative: PCN V, 250-500 mg PO BID-TID x 10 days or amoxicillin, 50 mg/kg QD x 10 days
-Allergic to PCN? Narrow-spectrum cephalosporins, clindamycin, azithromycin, or clarithromycin
-Anti-inflammatories
-Aspirin, 30-60 mg/kg/day divided QID x 2-6 weeks
-Treatment for HF as indicated, activity limitations
-Treatment following acute episode
-Prevention
-Regular, long-acting IM injections of benzathine PCN q 4 weeks x 5-10 years of therapy (or discontinue at age 21; whichever is longer)
-Alternatives: PCN V, sulfadiazine, erythromycin less effective
-Residual Valvular Damage: Replacement, if indicated
kawasaki disease
-Leading cause of acquired heart disease in children in the U.S.
-8% of pts < 5 years, M:F ratio is 1.5:1
-Diagnostic Criteria
-Fever > 4-5 days AND at least four of the following:
-Bilateral, painless, nonexudative conjunctivitis
-Lip or oral cavity changes (cracking, strawberry tongue, inflammation of oral mucosa)
-Cervical lymphadenopathy > 1.5 cm in diameter (usually unilateral)
-Polymorphous exanthem
-Extremity changes (redness/swelling of hands/feet with desquamation)
-Potential for cardiovascular complications
-Myocarditis, pericarditis, valvular heart disease, coronary arteritis
-Mild, transient dilation of CA to large aneurysms (most resolve spontaneously, others cause complication/require treatment)
-Risk: Males, infants < 6 months, those not treated with IVIG
-Treatment
-IVIG + high-dose aspirin (followed by low-dose x 6-8 weeks)
-2 g/kg IVIG over 10-12 hours and 80-100 mg/kg/day (or 30-50 mg/kg/day) divided QID
-Dual therapy with IVIG + infliximab or corticosteroid
-Reduces inflammation faster
-Effective in reducing CA dilation/aneurysms
-Consider for patients with persistent fever despite 1-2 infusions of IVIG
cardiomyopathies: dilated cardiomyopathy
-MC of the cardiomyopathies in children
-Causes: Primarily idiopathic; viral myocarditis, untreated tachyarrhythmias, L heart obstructive lesions, congenital abnormalities of the coronary arteries, medication toxicity, and genetic/metabolic diseases
-Clinical Manifestations
-Heart dilates > CO falls > decreased exercise tolerance, FTT, diaphoresis, and tachypnea
-Continued failure > Congestive signs (hepatomegaly, rales), prominent gallop on auscultation
-Imaging: Cardiomegaly with or without venous congestion
-ECG: Sinus tachycardia with ST segment changes
-Evaluation for supraventricular arrhythmias is critical (one of the few treatable and reversible causes of DCM in children
-Echocardiogram
-LA/LV enlargement with decreased ejection fraction
-End-diastolic/systolic dimensions increased
-Mitral insufficiency commonly seen
-Other Testing
-Cardiac catheterization: Evaluate hemodynamic stability and coronary artery anatomy
-Endomyocardial biopsies/PCR testing: Inflammation consistent with acute myocarditis, abnormal myocyte architecture, and myocardial fibrosis
-Electron micrographs: Mitochondrial/metabolic disorders
-Cardiopulmonary stress test: Response to therapy, assessment of cardiac limitations on exercise
-Treatment
-Afterload-reducing agents + diuretics
-Aspirin/warfarin to prevent thrombus formation
-Anti-arrhythmic therapy possible
-If medical management unsuccessful, heart transplant considered
cardiomyopathies: hypertrophic cardiomyopathy
-Leading cause of sudden cardiac death in children
-Familial (MC) and non-familial forms
-Familial: MC caused by mutation in one of several genes that encode proteins of the cardiac sarcomere
-Non-familial: Glycogen storage disease, Noonan syndrome, Friedreich ataxia, maternal gestational diabetes, mitochondrial disorders, and other metabolic disorders
-Asymptomatic
-Symptoms of inadequate coronary perfusion or HF: Angina, syncope, palpitations, or exercise intolerance
-Initial presentation may be SCD! – Precipitated by sporting activities
-Exam:
-L precordial bulge with diffuse PMI
-LV heave or S4 gallop
-If outflow obstruction > systolic ejection murmur
-Provoked by exercise or positional maneuvers that decrease LV volume (standing) – increase outflow over obstruction
cardiomyopathies: hypertrophic cardiomyopathy: dx and tx
-Echocardiogram
-Asymmetrical septal hypertrophy, concentric (metabolic/non-familial)
-Possible LV outflow obstruction
-Systolic function – hypercontractile; diastolic function almost always abnormal
-ECG
-Deep Q waves in inferolateral leads (increased mass of hypertrophied septum)
-LVH/LAE
-Other Testing
-Stress testing to evaluate for provocable LV outflow tract obstruction, ischemia, and arrhythmias; to determine prognosis
-Extreme LVH, blunted BP response to exercise > increased mortality
-Cardiac MRI: Defining areas of myocardial fibrosis/scarring
-Cardiac Catheterization
-Hemodynamic findings: Elevated LA pressure (impaired diastolic filling)
-Provocation of LV outflow obstruction, angiography, biopsy (myofiber disarray)
-Treatment/Prognosis
-Restricted from competitive athletics and isometric exercise
-Resting/latent outflow obstruction: B-blockers, verapamil, disopyramide
-Surgical myectomy with resection of -part of the hypertrophied septum
-Ethanol ablation (HCM with outflow obstruction)
-Ethanol into septal coronary artery > MI > reduction in septal size/outflow obstruction
-Not often performed in children
-Dual-chamber pacemaker/defibrillators not well studied in children
hypertension
-BP should be determined at every pediatric visit beginning at 3 years of age
-HTN prevalence approximately 3%
-Pediatric standards for BP published based on age, gender, and ht: dont need to know
-Normal: < 90th percentile AND < 120/80
-Pre-HTN: > 90th percentile OR > 120/80 and < 95th percentile
-Stage I HTN: > 95th percentile and < 99th percentile + 5 mmHg
-Stage II HTN: > 99th percentile + 5 mmHg
-If properly measured BP exceeds 95th percentile, measurement should be repeated on at least 3 separate occasions over a 2-4 week interval
-Ambulatory BP monitoring
Performed over 24 hours with at least 40 readings during waking and sleeping hours
-If BP persistently elevated, search for the cause should be undertaken
-Most HTN is primary
-Causes may include: Coarctation of the aorta, renal artery stenosis, chronic renal disease, pheochromocytoma, and medication side effects (steroids)
-Treatment (primary HTN)
-1st line: Lifestyle changes with diet and exercise!!!!!!!!!!!!!!
-Anti-HTN agents: ACEIs, ARBs, CCBs, diuretics
-Maximizing monotherapy prior to introducing a second agent remains official guideline
dyslipidemia
-Abnormal lipid levels are relatively common in children and adolescents (affects approx 1 in 5 adolescents)
-Lipid disorders are less common
-Severe hypercholesteremia (LDL > 190 mg/dL) – 1 in 250 adolescents
-Occur in assoc with/ obesity and accompanied by other risk factors that contribute to increased rates of CV and metabolic morbidity/mortality
-Abnormalities in lipid profile appearing early in childhood correlate with higher risk for CAD in adulthood
dyslipidemia: screening
-Routine screening is controversial
-Reasonable to check a fasting or non-fasting lipoprotein as early as 2 years of age with: family history of early CVD (< 55 in men, < 65 in women) or significant hypercholesterolemia (total cholesterol > 240 mg/dL), to detect familial hypercholesterolemia or other rare forms of hypercholesteremia
-AHA guidelines:
-Universal lipid screening at 9-11 years old and then at ages 17-21 years
-Checking fasting lipid panel indicated in children and adolescents with obesity or metabolic risk factors (high blood sugar, low HDL, high triglycerides, high BP, large waist circumference)
dyslipidemia: tx
-LDL > 130 mg/dL on two successive tests
-First-line: Lifestyle changes with dietary counseling and regular physical activity
-If unresponsive after 3-6 months and at extreme risk, drug therapy to decrease ASCVD risk
-Statins (coenzyme A reductase inhibitors) most commonly used and safe as early as 8-10 years
-Familial FH
-Cholestyramine (bile acid sequestrant) as early as 6 years, colesevelam (10 years)
-Ezetimibe (10 years) + statin
-Niacin for hypertriglyceridemia
syncope
-Transient LOC and postural tone resulting from an abrupt, temporary decrease in cerebral blood flow
-Majority of episodes self-limited and benign – vasovagal syncope
-Disorder of HR and BP control by ANS > causes hypotension or bradycardia
-Rarely first warning sign of arrhythmia, structural heart disease, or noncardiac disease
syncope: dx eval
-History: Age, time of day, state of hydration/nutrition, environmental conditions, patient’s activity/body position, frequency/duration of episodes, aura/prodrome/symptoms prior to episode
-Additional: Medications, history of viral illness, medical history (neurologic disorders, TBI, neurosurgical interventions), family history (cardiac, exertional, sudden death in children, seizures), witnesses
-Physical
-General: Hydration, nutritional status, thyroid disease manifestations
-Orthostatic VS
-Decrease in systolic BP of 20 mmHg or diastolic of 10 mmHg after 3 minutes of standing when compared to BP in supine or sitting position
-Pulse strength, rate, and differences between U/L extremities
-Heart murmurs > echocardiogram
-Phenotype of inherited genetic disorders
-ECG: Evaluate for HR, corrected QT interval, T-wave abnormalities, ventricular arrythmias, AV conduction disturbances, or Brugada syndrome (predisposes to VT)
vasovagal syncope
-Response of cardiac-CNS system reflex
-Prolonged/rapid assumption of an upright position > venous pooling in lower extremities > central hypovolemia leading to decreased venous return and SV
-Emotional/physical stress (pain/fright) > sympathetic response > tachycardia/vasoconstriction > subsequent parasympathetic response characterized by bradycardia/asystole and decrease in BP/SV
-Clinical Manifestations
-Prodrome: Nausea, epigastric pain, clammy sensation, pallor, dizziness, lightheadedness, tunnel vision, and weakness
-LOC > falls into supine state > restoration of venous return/central blood volume
-LOC is short (< 1-2 minutes), with rapid return to baseline behavior
-Myoclonic “jerks” common, loss of bowel/bladder uncommon
-Treatment
-Maintaining adequate intravascular volume
-Clear urine 5 times daily
-Increased salt intake/salt tablets
-Leg pumping, leg crossing, and squatting with presyncopal symptoms
-Regular aerobic exercise
-Medications (limited studies)
-Fludrocortisone (renal salt resorption), midodrine (alpha-agonist), B-blockers (target increased sympathetic output initiating reflex), vagolytic agents (disopyramide), SSRIs
cyanotic vs acyanotic
machinery like murmur, indomethacin, maintain patency- prostaglandin, cyanotic vs cyanotic defects
