FCPS TOACS · Anomalous Left Coronary Artery Mock Test

❓ Q1. Describe the ECG findings.

✅ Model Answer:
• Deep, wide Q waves in I, aVL, V5-V6 (anterolateral MI pattern).
• ST elevation and T-wave inversion in same leads.
• Pathognomonic for ALCAPA in an infant with heart failure.
• Indicates transmural infarction of anterolateral LV wall.

❓ Q2. Explain the pathophysiology of ALCAPA. Why does it cause myocardial infarction in infancy?

✅ Model Answer:
• LCA arises from pulmonary artery instead of aorta.
• After birth, PVR drops → PA pressure falls → LCA perfusion decreases → myocardial ischemia.
• Feeding increases myocardial O2 demand → worsens ischemia (angina equivalent).
• Leads to LV dysfunction, mitral regurgitation, and heart failure.

❓ Q3. What is the classic clinical presentation of ALCAPA in infancy?

✅ Model Answer:
• Onset: 2-6 months (when PVR drops).
• Feeding difficulties: poor feeding, pallor, diaphoresis, irritability during feeds (angina).
• Heart failure: tachypnea, tachycardia, hepatomegaly, failure to thrive.
• ECG: deep Q waves in I, aVL, V5-V6.

❓ Q4. What are the echocardiographic findings in ALCAPA? How do you confirm the diagnosis?

✅ Model Answer:
• Echo: LV dysfunction, mitral regurgitation, LCA origin from PA (short-axis view).
• Color Doppler: retrograde flow in LCA (coronary steal).
• Confirmation: cardiac catheterization (gold standard) or CT/MRI angiography.

❓ Q5. What is the definitive treatment for ALCAPA? What is the Takeuchi procedure?

✅ Model Answer:
• Definitive: surgical reimplantation of LCA to aorta (urgent).
• Takeuchi procedure: intrapulmonary tunnel for LCA when direct reimplantation not feasible.
• Pre-op stabilization: inotropes, diuretics, ECMO if needed.

❓ Q6. What is the differential diagnosis of ALCAPA in an infant with heart failure and ECG changes?

✅ Model Answer:
• DCM (no Q waves), myocarditis (no Q waves), endocardial fibroelastosis (LVH, no Q waves).
• Hypertrophic cardiomyopathy (Q waves in septal leads, not lateral).
• Duchenne muscular dystrophy (later onset).
• Key: infantile heart failure + deep Q waves in I, aVL, V5-V6 = ALCAPA.

❓ Q7. A child with ALCAPA presents with severe heart failure and cardiogenic shock. What is the role of ECMO?

✅ Model Answer:
• ECMO: bridge to surgery or recovery for refractory cardiogenic shock.
• Provides circulatory support while stabilizing patient.
• Improves survival in critically ill infants before surgical repair.

❓ Q8. Why is mitral regurgitation common in ALCAPA? Does it resolve after surgery?

✅ Model Answer:
• Mechanism: ischemia of posteromedial papillary muscle (supplied by LCA).
• MR often improves after reimplantation as LV function recovers.
• 5-10% may require mitral valve surgery later.

❓ Q9. What is the role of coronary collaterals in ALCAPA? Why do some infants survive longer?

✅ Model Answer:
• Collaterals from RCA to LCA provide some perfusion to LV myocardium.
• Coronary steal: blood flows retrograde into PA, worsening ischemia.
• Collaterals may allow survival to 6-12 months but do not eliminate need for surgery.

❓ Q10. What is the long-term prognosis for an infant with ALCAPA after surgical repair?

✅ Model Answer:
• Excellent: >90% survival with early surgery.
• LV function improves significantly; MR often resolves.
• Long-term: coronary stenosis (rare), arrhythmias, need lifelong follow-up.

❓ Q11. What is the role of cardiac catheterization in ALCAPA? Is it always necessary?

✅ Model Answer:
• Gold standard for diagnosis – shows LCA origin from PA.
• Not always necessary if echo and CT/MRI clearly demonstrate anatomy.
• Reserved for unclear anatomy or pre-operative assessment.

❓ Q12. What are the post-operative complications after ALCAPA repair?

✅ Model Answer:
• Coronary stenosis, pulmonary artery stenosis (Takeuchi), residual MR.
• LV dysfunction, arrhythmias, low cardiac output syndrome.
• Close follow-up with echo, ECG, and MRI.

❓ Q13. What is the difference between direct reimplantation and the Takeuchi procedure? Which is preferred?

✅ Model Answer:
• Direct reimplantation: LCA anastomosed directly to aorta – preferred if feasible.
• Takeuchi: intrapulmonary tunnel – used when LCA too short.
• Direct reimplantation has better long-term outcomes (lower stenosis risk).

⚕️ FCPS MCPS IMM MD Paediatrics TOACS · Mock Test