Congenital Heart Disease Questions - Set 2¶
Question 1¶
A neonate with HLHS has an intact atrial septum diagnosed prenatally. What is the optimal delivery plan?
A) Routine delivery at local hospital with transfer after birth B) Delivery at cardiac center with immediate catheter intervention C) Cesarean section at 34 weeks D) Delivery at cardiac center, wait for symptoms before intervention E) Fetal intervention is mandatory
Answer
**Correct Answer: B** HLHS with intact/restrictive atrial septum requires: - Delivery at cardiac surgical center - Immediate access to catheterization for septostomy - Often emergent intervention within hours of birth - Fetal intervention is considered at select centers **Board Pearl:** HLHS + intact atrial septum = delivery at cardiac center, emergent septostomyQuestion 2¶
What is the most common cause of death in the first month after Norwood operation?
A) Shunt thrombosis B) Sepsis C) Interstage mortality at home D) Arch obstruction E) Neoaortic regurgitation
Answer
**Correct Answer: A** **Shunt thrombosis** (BT shunt occlusion) is the most common cause of early post-Norwood death: - Sudden cyanosis and cardiovascular collapse - Aspirin prophylaxis is standard - Some centers use heparin early post-op **Board Pearl:** Post-Norwood: shunt thrombosis = most common early cause of deathQuestion 3¶
In the Fontan circulation, what maintains cardiac output?
A) Right ventricular contraction B) Respiratory variation and negative intrathoracic pressure C) Left atrial contraction D) Aortopulmonary collaterals E) Pulmonary valve function
Answer
**Correct Answer: B** Fontan is a "passive" pulmonary circulation. Blood flow to lungs depends on: - **Respiratory variation** (negative pressure draws blood in) - Low PVR - Adequate systemic venous pressure - No RV to generate pulsatile flow **Board Pearl:** Fontan = passive circulation; depends on respiration and low PVRQuestion 4¶
A 2-year-old with unrepaired complete AVSD develops Eisenmenger syndrome. What is the expected shunt direction?
A) Left-to-right at atrial and ventricular level B) Bidirectional at atrial level, right-to-left at ventricular level C) Right-to-left at both levels D) Left-to-right at atrial level only E) No shunting due to equalized pressures
Answer
**Correct Answer: C** In Eisenmenger with AVSD: - PVR exceeds SVR - Both atrial and ventricular shunts reverse to **R→L** - Results in cyanosis - Surgery is contraindicated **Board Pearl:** Eisenmenger AVSD = R→L shunt at both atrial and ventricular levelsQuestion 5¶
What is the most common long-term complication after atrial switch (Mustard/Senning) for d-TGA?
A) Coronary artery stenosis B) Baffle obstruction or leak C) Systemic RV failure D) Pulmonary vein stenosis E) Aortic root dilation
Answer
**Correct Answer: C** **Systemic RV failure** is the major long-term issue: - RV not designed for systemic pressure long-term - Progressive dysfunction over decades - Often requires transplant eventually - Also see arrhythmias and baffle problems **Board Pearl:** Atrial switch = systemic RV; progressive failure is the major issueQuestion 6¶
A 5-year-old with TOF and absent pulmonary valve has severe respiratory symptoms. What is the mechanism?
A) Pulmonary overcirculation B) Large airway compression by dilated PAs C) Restrictive lung disease D) Pulmonary hypertension E) Diaphragm paralysis
Answer
**Correct Answer: B** TOF with absent pulmonary valve: - Massive PA dilation from free PR + aneurysmal PAs - **Bronchial compression** (especially left main) - Bronchomalacia develops - Respiratory issues may persist post-repair **Board Pearl:** TOF absent PV = dilated PAs compress airways; respiratory morbidity highQuestion 7¶
What percentage of VSDs close spontaneously by age 2?
A) 10-20% B) 30-40% C) 50-60% D) 70-80% E) 90-95%
Answer
**Correct Answer: D** **70-80%** of small-moderate muscular and perimembranous VSDs close spontaneously, usually by age 2. Factors favoring closure: - Small size - Muscular location - Presence of septal aneurysm tissue **Board Pearl:** 70-80% of small VSDs close spontaneously by age 2Question 8¶
In double outlet right ventricle (DORV), what determines if arterial switch versus intraventricular repair is performed?
A) Size of the VSD B) Relationship of VSD to great arteries C) Presence of pulmonary stenosis D) Coronary artery pattern E) Aortic arch anatomy
Answer
**Correct Answer: B** DORV repair depends on **VSD-great artery relationship**: - Subaortic VSD → Intraventricular tunnel repair - Subpulmonic VSD → Arterial switch (Taussig-Bing) - Doubly-committed or remote → More complex approaches - PS also affects approach **Board Pearl:** DORV: VSD location determines repair type (subaortic=tunnel, subpulmonic=ASO)Question 9¶
A patient with tricuspid atresia and normally related great arteries (Type 1b) has inadequate pulmonary blood flow. What is the source of pulmonary blood flow?
A) Patent ductus arteriosus B) Atrial septal defect C) Aortopulmonary collaterals D) VSD with unobstructed flow to PA E) Coronary to PA fistula
Answer
**Correct Answer: A** In tricuspid atresia 1b (with PS): - Blood reaches lungs via **PDA** - VSD present but restrictive or PS limits flow - Ductal-dependent pulmonary circulation - Needs BT shunt or stented PDA **Board Pearl:** Tricuspid atresia 1b = ductal-dependent pulmonary blood flowQuestion 10¶
What is the Rastelli classification based on in complete AVSD?
A) Size of the primum ASD B) Morphology of the superior bridging leaflet C) Degree of LV-RV imbalance D) Presence of common vs separate AV valve orifices E) Attachment of chordae to the ventricular septum