Comprehensive Pediatric Cardiology Board Questions¶

Difficulty Key: - ★★★ Must-know (frequently tested, foundational) - ★★ Should-know (important, less common) - ★ Good-to-know (advanced/nuanced)

Section 1: Kawasaki Disease (Questions 1-15)¶

Question 1 ★★★¶

A 4-year-old presents with 6 days of fever, bilateral conjunctival injection, strawberry tongue, cervical lymphadenopathy, and truncal rash. Echo shows LAD diameter of 3.5mm (Z-score +2.8). What is the initial treatment?

A) IVIG 2g/kg alone B) IVIG 2g/kg + high-dose aspirin C) IVIG 2g/kg + high-dose aspirin + corticosteroids D) Infliximab E) Aspirin alone

Answer

**Correct Answer: C** This patient has complete Kawasaki disease WITH coronary artery aneurysm at diagnosis (Z-score ≥2.5). Per 2024 AHA guidelines, patients with high-risk features (including CAA at diagnosis) should receive **intensified initial therapy**: IVIG + high-dose aspirin + adjunctive corticosteroids. **Board Pearl:** Z-score ≥2.5 at diagnosis = high risk → intensify initial treatment

Question 2 ★★¶

In the KAWARACE trial, what was found regarding aspirin dosing in acute Kawasaki disease?

A) High-dose aspirin prevents coronary aneurysms B) High-dose aspirin reduces fever duration significantly C) No significant difference between high-dose and low-dose aspirin D) Low-dose aspirin increases CAA risk E) Aspirin should be avoided in acute phase

Answer

**Correct Answer: C** The KAWARACE trial (2023) found **no significant difference** between high-dose (30-50 mg/kg/day) and low-dose (3-5 mg/kg/day) aspirin in acute Kawasaki disease. **Board Pearl:** KAWARACE challenges traditional high-dose aspirin approach

Question 3 ★★★¶

A 2-year-old with Kawasaki disease receives IVIG and aspirin. 48 hours later, fever persists. What is the next step?

A) Repeat IVIG 2g/kg B) Add corticosteroids C) Start infliximab D) Continue observation for 72 more hours E) Discharge with close follow-up

Answer

**Correct Answer: A** **IVIG-resistant** Kawasaki is defined as persistent/recurrent fever ≥36 hours after initial IVIG. First-line treatment for IVIG resistance is a **second dose of IVIG 2g/kg**. **Board Pearl:** Persistent fever >36h post-IVIG = resistant → second IVIG dose

Question 4 ★★★¶

Which coronary artery Z-score threshold defines "giant aneurysm" in Kawasaki disease?

A) Z ≥ 2.5 B) Z ≥ 5 C) Z ≥ 7.5 D) Z ≥ 10 or absolute ≥8mm E) Absolute diameter ≥5mm

Answer

**Correct Answer: D** **Giant aneurysm: Z-score ≥10 or absolute diameter ≥8mm** Classification: - No involvement: Z < 2.0 - Dilation: Z 2.0-2.5 - Small aneurysm: Z 2.5-5.0 - Medium aneurysm: Z 5.0-10 - Giant aneurysm: Z ≥10 or ≥8mm **Board Pearl:** Giant CAA = Z ≥10 or ≥8mm → needs triple therapy (ASA + warfarin + clopidogrel)

Question 5 ★★★¶

A 6-month-old has 7 days of unexplained fever, elevated CRP (85), and elevated ALT. Echo shows coronary Z-score of +3.0. What is the diagnosis?

A) Incomplete Kawasaki disease B) Complete Kawasaki disease C) Viral myocarditis D) Sepsis E) Fever of unknown origin

Answer

**Correct Answer: A** This is **incomplete Kawasaki disease**. The patient has: - Prolonged fever (≥5 days unexplained) - Only 2 clinical criteria visible (elevated CRP, elevated ALT are lab features) - BUT coronary artery abnormality (Z ≥2.5 = diagnostic) Infants <6 months are at highest risk for incomplete KD and coronary involvement. **Board Pearl:** Fever + coronary abnormality = Kawasaki regardless of clinical criteria

Section 2: Hypertrophic Cardiomyopathy (Questions 6-15)¶

Question 6 ★★¶

A 16-year-old with HCM has a calculated 5-year SCD risk of 8% using the Norrish pediatric HCM risk model. What is the recommendation regarding ICD?

A) No ICD indicated - risk too low B) ICD recommended (Class I) C) ICD should be discussed (Class IIa) D) Reassess in 1 year before deciding E) Cardiac transplant evaluation

Answer

**Correct Answer: C** Per 2024 guidelines, ICD is reasonable (Class IIa) when 5-year SCD risk is ≥6% using validated pediatric models. Risk thresholds: - <4%: Generally no ICD - 4-6%: Individualize - ≥6%: ICD reasonable (Class IIa) **Board Pearl:** Norrish risk ≥6% = discuss ICD

Question 7 ★★¶

Which medication has demonstrated myosin inhibition as mechanism of action for treating obstructive HCM?

A) Metoprolol B) Verapamil C) Disopyramide D) Mavacamten E) Diltiazem

Answer

**Correct Answer: D** **Mavacamten** is a first-in-class cardiac myosin inhibitor that reduces hypercontractility in HCM. EXPLORER-HCM (2020) showed significant gradient reduction. **Board Pearl:** Mavacamten = myosin inhibitor; EXPLORER-HCM trial

Question 8 ★★¶

What percentage of HCM cases are caused by sarcomere gene mutations?

A) 10-20% B) 40-60% C) 70-80% D) 90-95% E) 100%

Answer

**Correct Answer: B** 40-60% of HCM cases have identifiable sarcomere mutations. The most common genes are: - MYH7 (beta-myosin heavy chain) - MYBPC3 (myosin-binding protein C) **Board Pearl:** HCM is genetically heterogeneous; 40-60% have identifiable mutations

Question 9 ★★★¶

Which physical exam maneuver increases the murmur of hypertrophic obstructive cardiomyopathy?

A) Squatting B) Handgrip C) Valsalva (strain phase) D) Passive leg elevation E) None of the above

Answer

**Correct Answer: C** **Valsalva strain phase** decreases preload, which INCREASES the HCM murmur by worsening the LVOT obstruction. Maneuvers that DECREASE preload → INCREASE HCM murmur: - Valsalva strain phase - Standing from squat - Amyl nitrite **Board Pearl:** Valsalva/standing increases HCM murmur; squatting decreases it

Question 10 ★★¶

A 12-year-old with HCM has resting LVOT gradient of 85mmHg despite maximum medical therapy. What is the recommended intervention?

A) Continue medical therapy B) ICD implantation C) Alcohol septal ablation D) Septal myectomy E) Cardiac transplant

Answer

**Correct Answer: D** For children with refractory obstructive HCM, **surgical septal myectomy** is preferred over alcohol ablation. Alcohol septal ablation is generally reserved for adults who are not surgical candidates. **Board Pearl:** Septal myectomy preferred over alcohol ablation in children

Section 3: Channelopathies (Questions 11-20)¶

Question 11 ★★¶

A 14-year-old female has genetically confirmed LQTS Type 2 (KCNH2 mutation). Her QTc is 510ms. She is asymptomatic. What is the recommended treatment?

A) No treatment needed if asymptomatic B) Beta-blocker only C) ICD primary prevention D) Beta-blocker + consider ICD discussion E) Mexiletine

Answer

**Correct Answer: D** This patient has multiple risk factors: - LQT2 (higher risk genotype in females) - QTc >500ms - Female sex Beta-blocker is mandatory. Given QTc >500 and LQT2 in female, ICD discussion is warranted. **Board Pearl:** LQT2 female + QTc >500 = higher risk; ICD discussion warranted

Question 12 ★★¶

Which LQTS genotype is most responsive to mexiletine therapy?

A) LQT1 B) LQT2 C) LQT3 D) LQT5 E) LQT7

Answer

**Correct Answer: C** **LQT3** is caused by SCN5A (sodium channel) mutations with gain-of-function. Mexiletine blocks sodium channels, directly addressing the pathophysiology. **Board Pearl:** LQT3 = sodium channel → mexiletine as adjunct therapy

Question 13 ★★★¶

Which arrhythmia trigger is most characteristic of LQT1?

A) Sleep/rest B) Exercise (especially swimming) C) Auditory stimuli (alarm clocks) D) Emotional stress E) Fever

Answer

**Correct Answer: B** **LQT1** (KCNQ1 potassium channel) events are typically triggered by: - Exercise (especially swimming) - Sympathetic activation - Physical exertion Swimming is particularly dangerous in LQT1. **Board Pearl:** LQT1 = exercise/swimming triggers; LQT2 = auditory triggers

Question 14 ★★★¶

A 10-year-old collapses while running during soccer. Rhythm strip shows polymorphic VT. Resting ECG is normal. Family history: paternal aunt died suddenly at 32 during exercise. What is the most likely diagnosis?

A) Long QT syndrome B) Brugada syndrome C) CPVT D) HCM E) AAOCA

Answer

**Correct Answer: C** **CPVT** (Catecholaminergic Polymorphic VT) presents with: - Exercise-induced bidirectional or polymorphic VT - Normal resting ECG and echo - Family history of SCD during exertion The normal resting ECG excludes LQTS. The exertional nature and polymorphic VT are classic CPVT. **Board Pearl:** Normal resting ECG + exercise-induced polymorphic VT = think CPVT

Question 15 ★★★¶

What is first-line therapy for CPVT?

A) Mexiletine B) Verapamil C) Nadolol D) Flecainide E) ICD alone

Answer

**Correct Answer: C** **Non-selective beta-blockers** (nadolol, propranolol) are first-line for CPVT. Nadolol is often preferred due to once-daily dosing and longer half-life. Flecainide is added if beta-blocker alone insufficient. **Board Pearl:** CPVT first-line = non-selective beta-blocker (nadolol preferred)

Question 16 ★★¶

Which feature most suggests Brugada syndrome rather than an athlete's heart on ECG?

A) Sinus bradycardia B) Coved ST elevation in V1-V2 C) Incomplete RBBB D) High QRS voltage E) Early repolarization in lateral leads

Answer

**Correct Answer: B** **Type 1 Brugada pattern:** Coved ST elevation ≥2mm in V1-V2 followed by T-wave inversion. This is distinctly different from athlete's heart, which may show early repolarization but not the coved morphology. **Board Pearl:** Coved ST elevation V1-V2 = Brugada Type 1 (diagnostic pattern)

Section 4: Syncope (Questions 17-20)¶

Question 17 ★★★¶

Which feature MOST strongly suggests cardiac (vs. vasovagal) etiology in a teenager with syncope?

A) Occurred after standing for 30 minutes B) Associated nausea and diaphoresis before event C) Occurred while playing basketball D) Had brief jerking movements after collapse E) Full recovery within 2 minutes

Answer

**Correct Answer: C** **Exertional syncope** (syncope DURING exercise) is a major red flag for cardiac etiology (HCM, LQTS, CPVT, AAOCA) and mandates full cardiac evaluation. **Board Pearl:** Syncope DURING exercise = cardiac until proven otherwise

Question 18 ★★¶

A 14-year-old has recurrent syncope during choir concerts. Each episode is preceded by lightheadedness. What is the likely diagnosis?

A) LQTS B) Vasovagal syncope C) Situational syncope D) CPVT E) Seizure

Answer

**Correct Answer: C** **Situational syncope** - triggered by specific situations (singing, coughing, urination). Prolonged standing + Valsalva-like maneuvers during singing → decreased venous return → syncope. **Board Pearl:** Syncope with specific triggers (singing, coughing) = situational syncope

Section 5: Pulmonary Hypertension (Questions 19-25)¶

Question 19 ★★¶

A 3-year-old with a large VSD has mean PA pressure of 55 mmHg and PVR of 9 Wood units. Vasoreactivity testing shows no response. What is the recommendation?

A) Proceed with VSD closure B) VSD closure is contraindicated C) Treat with sildenafil for 6 months then reassess D) Fenestrated VSD closure E) Heart-lung transplant

Answer

**Correct Answer: B** With PVR of 9 WU (above 6-8 WU threshold) and no vasoreactivity, the patient has **irreversible pulmonary vascular disease**. VSD closure would result in RV failure. **Board Pearl:** PVR >6-8 WU without vasoreactivity = inoperable

Question 20 ★★¶

What is the mechanism of action of sildenafil in pulmonary hypertension?

A) Endothelin receptor antagonism B) Prostacyclin pathway activation C) PDE-5 inhibition increasing cGMP D) Calcium channel blockade E) Direct smooth muscle relaxation

Answer

**Correct Answer: C** **Sildenafil** is a PDE-5 inhibitor that prevents breakdown of cGMP, leading to pulmonary vasodilation. Three pathways in PH therapy: - Endothelin pathway (bosentan) - NO-cGMP pathway (sildenafil) - Prostacyclin pathway (epoprostenol) **Board Pearl:** Sildenafil = PDE-5 inhibitor → increases cGMP → pulmonary vasodilation

Section 6: CCHD Screening (Questions 21-25)¶

Question 21 ★★★¶

A newborn at 28 hours has: Right hand 97%, Right foot 93%, difference 4%. After 1 retest: Right hand 96%, Right foot 92%, difference 4%. Per 2025 guidelines, what is the next step?

A) Pass - discharge with routine follow-up B) Pass after one more retest C) Fail - obtain echocardiogram D) Indeterminate - repeat tomorrow E) Fail - immediate cardiology consult without echo

Answer

**Correct Answer: C** Per **2025** algorithm: - Initial: 93% + 4% difference → RETEST - After 1 retest: Still <95% or >3% difference → **FAIL** 2025 update: **Only 1 retest allowed** (previously 2). **Board Pearl:** 2025 CCHD - only 1 retest allowed; then PASS or FAIL

Question 22 ★★★¶

Which congenital heart defect is most commonly missed by CCHD pulse oximetry screening?

A) d-TGA B) HLHS C) Coarctation of the aorta D) Truncus arteriosus E) Tetralogy of Fallot

Answer

**Correct Answer: C** **Coarctation** is the lesion most commonly missed because: - The PDA maintains normal saturations initially - Coarctation doesn't cause cyanosis - Failure occurs after PDA closes (after discharge) **Board Pearl:** Normal CCHD screen does NOT rule out coarctation

Section 7: Fontan (Questions 23-30)¶

Question 23 ★★¶

A 15-year-old Fontan patient presents with ascites and lower extremity edema. Albumin is 1.9 g/dL. Stool alpha-1 antitrypsin is elevated. What is the diagnosis?

A) Fontan failure B) Protein-losing enteropathy C) Fontan-associated liver disease D) Right heart failure E) Nephrotic syndrome

Answer

**Correct Answer: B** **PLE** is characterized by: - Hypoalbuminemia - Edema/ascites - Elevated stool alpha-1 antitrypsin - Often lymphopenia and hypogammaglobulinemia **Board Pearl:** PLE = hypoalbuminemia + elevated stool α1-antitrypsin in Fontan

Question 24 ★★¶

What is the most common late arrhythmia in Fontan patients?

A) Ventricular tachycardia B) Complete heart block C) Intra-atrial reentrant tachycardia (IART) D) Wolff-Parkinson-White E) Sinus bradycardia

Answer

**Correct Answer: C** **IART** (atrial flutter-type arrhythmia) occurs in up to 50% of Fontan patients over their lifetime due to atrial scarring and dilation. **Board Pearl:** IART = most common arrhythmia in Fontan; requires aggressive treatment

Question 25 ★¶

What is the 30-year survival estimate for modern Fontan patients?

A) 30-40% B) 50-60% C) 70-80% D) 90-95% E) >95%

Answer

**Correct Answer: C** 30-year Fontan survival is approximately **70-80%** with modern techniques. However, virtually all develop complications over time. **Board Pearl:** Fontan is palliative, not curative; 70-80% 30-year survival

Section 8: Sports Cardiology (Questions 26-30)¶

Question 26 ★★¶

Per 2025 guidelines, which patient with known cardiac condition MAY participate in competitive sports using shared decision-making?

A) 16-year-old with AAOLCA (interarterial course) B) 15-year-old with LQTS on beta-blocker, asymptomatic C) 14-year-old with CPVT on beta-blocker D) 17-year-old with Eisenmenger syndrome E) 18-year-old with severe aortic stenosis

Answer

**Correct Answer: B** 2025 guidelines allow **shared decision-making** for asymptomatic LQTS on appropriate therapy. - AAOLCA: Restrict until repaired - CPVT: Restrict from competitive sports - Eisenmenger: No competitive sports - Severe AS: Restrict **Board Pearl:** LQTS can participate with SDM (beta-blocker, AED access)

Question 27 ★★★¶

How long should an athlete with myocarditis refrain from competitive sports?

A) 1-2 weeks B) 2-4 weeks C) 3-6 months D) 12 months E) Permanently restricted

Answer

**Correct Answer: C** **3-6 months** minimum restriction for myocarditis. Return requires: - Asymptomatic - Normal echo - Normal Holter - Normal exercise test - CMR showing no active inflammation **Board Pearl:** Myocarditis = 3-6 month restriction before return to play

Section 9: Myocarditis & Pericarditis (Questions 28-35)¶

Question 28 ★★★¶

Which imaging modality is the gold standard for diagnosing myocarditis?

A) Echocardiogram B) CT angiography C) Cardiac MRI D) Nuclear perfusion imaging E) Endomyocardial biopsy

Answer

**Correct Answer: C** **Cardiac MRI** is the gold standard non-invasive test showing: - Edema (T2-weighted) - Late gadolinium enhancement (fibrosis) - Lake Louise criteria Biopsy is gold standard for definitive diagnosis but rarely performed. **Board Pearl:** CMR = gold standard imaging for myocarditis (Lake Louise criteria)

Question 29 ★★★¶

Which medication reduces recurrence of pericarditis?

A) Ibuprofen B) Prednisone C) Colchicine D) Acetaminophen E) Aspirin

Answer

**Correct Answer: C** **Colchicine** significantly reduces recurrence rates in acute and recurrent pericarditis (COPE, CORP trials). - First episode: 3 months - Recurrence: 6 months **Board Pearl:** Colchicine = key to preventing pericarditis recurrence

Question 30 ★★¶

A 13-year-old has typical pericarditis symptoms with troponin elevation. How does this change management?

A) No change - treat as pericarditis B) Longer activity restriction (3-6 months vs 2-4 weeks) C) Emergent catheterization D) Immediate ICD evaluation E) IVIG administration

Answer

**Correct Answer: B** Troponin elevation = **myopericarditis** = myocardial involvement. Activity restriction: - Pericarditis alone: 2-4 weeks - Myopericarditis: 3-6 months (same as myocarditis) **Board Pearl:** Troponin elevation in pericarditis = myopericarditis → longer restriction

Section 10: MIS-C (Questions 31-35)¶

Question 31 ★★¶

What percentage of MIS-C patients have cardiac involvement?

A) 10-20% B) 30-40% C) 50-60% D) 80-90% E) 100%

Answer

**Correct Answer: D** **80-90%** of MIS-C patients have cardiac involvement including: - LV dysfunction (50%) - Coronary abnormalities (20%) - Shock requiring inotropes (35-50%) - Elevated BNP/troponin (80-90%) **Board Pearl:** MIS-C has high cardiac involvement (80-90%)

Question 32 ★★★¶

What is the first-line treatment for MIS-C?

A) Methylprednisolone alone B) IVIG alone C) IVIG + methylprednisolone D) Tocilizumab E) Supportive care only

Answer

**Correct Answer: C** Per 2021 ACR guidelines, **IVIG + corticosteroids** together is recommended first-line for MIS-C (better outcomes than either alone - BATS/OVERCOMING studies). **Board Pearl:** MIS-C first-line = IVIG + steroids together

Section 11: Neuromuscular Diseases (Questions 33-35)¶

Question 33 ★★★¶

At what age should prophylactic ACE inhibitor be started in Duchenne muscular dystrophy?

A) At diagnosis B) Age 5 C) Age 10 D) When EF drops below 55% E) When symptoms develop

Answer

**Correct Answer: C** Prophylactic ACE inhibitor (or ARB) should be started by **age 10** in DMD, regardless of cardiac function. Evidence shows this delays cardiomyopathy onset. **Board Pearl:** DMD: Start ACE-I by age 10 regardless of EF

Question 34 ★★¶

What is the characteristic ECG finding in Duchenne muscular dystrophy?

A) Left axis deviation B) Deep Q waves in lateral leads C) First-degree AV block D) Right bundle branch block E) Short PR interval

Answer

**Correct Answer: B** DMD ECG pattern: - **Deep narrow Q waves in I, aVL, V5-V6** (lateral leads) - Tall R waves in V1 (R/S ratio >1) - ST-T changes laterally This reflects posterolateral fibrosis from dystrophin deficiency. **Board Pearl:** DMD ECG = tall R in V1 + deep Q waves laterally

Question 35 ★¶

A patient with Friedreich ataxia develops HCM. What is unique about cardiac monitoring in this population?

A) Less frequent than typical HCM B) Annual CMR is recommended C) ECG is unreliable D) May develop diabetes affecting cardiac care E) No ICD is ever indicated

Answer

**Correct Answer: D** Friedreich ataxia is associated with both HCM AND diabetes mellitus. Cardiac management must account for: - Diabetes management - Difficulty with exercise testing (ataxia) - Progressive nature of both conditions - Overall prognosis affecting intervention decisions **Board Pearl:** Friedreich ataxia = HCM + diabetes; affects overall management

For additional questions, see topic-specific question banks in the /board-prep/self-assessment/ directory