Congenital Heart Disease Questions - Set 1¶
Question 1¶
A newborn with d-TGA undergoes balloon atrial septostomy. Post-procedure SpO2 improves from 65% to 82%. What determines the degree of mixing after septostomy?
A) Size of the ASD created B) Pulmonary vascular resistance C) Presence of VSD D) All of the above E) Ductus arteriosus patency only
Answer
**Correct Answer: D** All factors affect mixing in d-TGA: - Larger ASD = more atrial mixing - Lower PVR = more pulmonary blood flow to mix - VSD provides additional mixing site - PDA provides additional mixing **Board Pearl:** d-TGA mixing depends on ASD size, PVR, and additional shunts (VSD, PDA)Question 2¶
Which surgical repair is preferred for infants with complete AVSD and Down syndrome?
A) Two-patch technique B) Single-patch technique C) Australian technique (modified single-patch) D) Any technique - outcomes are equivalent E) Staged repair with PA band first
Answer
**Correct Answer: C** The **Australian/modified single-patch technique** is increasingly preferred as it: - Avoids dividing the bridging leaflets - Reduces residual LAVV regurgitation - Has excellent outcomes in Down syndrome patients **Board Pearl:** Australian technique = modified single-patch; may have lower LAVV regurgitation ratesQuestion 3¶
A 6-month-old with tetralogy of Fallot has a hypercyanotic spell during blood draw. Initial SpO2 is 45%. What is the FIRST intervention?
A) Intubation B) Morphine 0.1 mg/kg C) Knee-chest position D) Phenylephrine bolus E) Propranolol IV
Answer
**Correct Answer: C** **Knee-chest position** is first-line for tet spells: - Increases SVR (reduces R→L shunt) - Increases venous return - Can be done immediately Sequence: Position → Oxygen → Morphine → Fluid → Phenylephrine → Propranolol → Surgery if refractory **Board Pearl:** Tet spell first step = knee-chest position (increases SVR)Question 4¶
What is the most common associated cardiac anomaly in patients with coarctation of the aorta?
A) VSD B) Bicuspid aortic valve C) Mitral valve abnormality D) ASD E) PDA
Answer
**Correct Answer: B** **Bicuspid aortic valve** is present in 50-85% of coarctation patients. This has major long-term implications: - May develop aortic stenosis - May develop aortic regurgitation - Risk of aortic root dilation - Requires lifelong surveillance **Board Pearl:** Coarctation + BAV in 50-85%; BAV may become dominant issue long-termQuestion 5¶
A patient with Ebstein anomaly has severe tricuspid regurgitation with RA dilation. ECG shows WPW pattern. What is the most appropriate management?
A) Digoxin for rate control B) Propranolol for SVT prophylaxis C) Electrophysiology study and ablation D) Observation only E) Amiodarone prophylaxis
Answer
**Correct Answer: C** **EP study and ablation** is indicated because: - Ebstein has 20-30% incidence of WPW - Often has multiple accessory pathways - Ablation before surgical repair is preferred - Digoxin is relatively contraindicated in WPW **Board Pearl:** Ebstein + WPW = EP study/ablation; multiple pathways commonQuestion 6¶
Which lesion is MOST likely to be missed by fetal echocardiography?
A) Hypoplastic left heart syndrome B) Complete AVSD C) Total anomalous pulmonary venous return D) Tetralogy of Fallot E) d-TGA
Answer
**Correct Answer: C** **TAPVR** is most commonly missed because: - Four-chamber view appears normal - Pulmonary veins are difficult to image - No obvious structural abnormality - Requires specific attention to PV drainage Detection rate: TAPVR ~50% vs HLHS >95% **Board Pearl:** TAPVR most commonly missed on fetal echo - normal 4-chamber viewQuestion 7¶
A Fontan patient develops atrial flutter with 2:1 conduction and ventricular rate of 150 bpm. BP is 75/50. What is the most appropriate immediate treatment?
A) Adenosine 0.1 mg/kg B) IV amiodarone C) Synchronized cardioversion D) Digoxin loading E) IV diltiazem
Answer
**Correct Answer: C** **Synchronized cardioversion** is indicated for: - Hemodynamic instability (BP 75/50) - Fontan patients are preload-dependent - Loss of AV synchrony is poorly tolerated - Atrial flutter in Fontan = emergency **Board Pearl:** Unstable atrial flutter in Fontan = immediate cardioversionQuestion 8¶
What is the 30-year survival rate after arterial switch operation for d-TGA?
A) 50-60% B) 60-70% C) 75-85% D) 90-95% E) >98%
Answer
**Correct Answer: D** Modern ASO has excellent outcomes: - Operative mortality <2% - 30-year survival 90-95% - Main late issues: neoaortic root dilation, coronary stenosis, branch PA stenosis **Board Pearl:** ASO 30-year survival ~90-95%; watch for neo-aortic dilationQuestion 9¶
In truncus arteriosus, what determines the classification (Type I, II, III)?
A) Size of the VSD B) Origin of the pulmonary arteries from the truncal root C) Presence of truncal valve regurgitation D) Aortic arch sidedness E) Coronary artery anatomy
Answer
**Correct Answer: B** Collett-Edwards classification: - **Type I**: Main PA arises from truncus, then bifurcates - **Type II**: Branch PAs arise separately but close together - **Type III**: Branch PAs arise separately, far apart - Type IV (now considered pulmonary atresia with VSD) **Board Pearl:** Truncus types based on PA origin from truncal rootQuestion 10¶
A 15-year-old with repaired TOF has RV EDVi of 165 mL/m² on MRI with RVEF of 48%. He is asymptomatic. What is the recommendation?
A) Continue observation, repeat MRI in 3 years B) Pulmonary valve replacement is indicated C) Start heart failure medications D) Exercise restriction only E) List for transplant evaluation