Congenital Heart Disease USMLE Step 1 Practice Question
A 2-day-old male infant born at 39 weeks gestation presents with progressive cyanosis and respiratory distress. Vital signs show SpO2 of 28% on room air, heart rate 168 bpm, respiratory rate 62/min, and blood pressure 58/35 mmHg. Physical examination reveals a single loud S2 and no significant murmur. Chest X-ray shows cardiomegaly with a narrow mediastinum and increased pulmonary vascular markings. Echocardiography demonstrates a single arterial trunk originating from the heart that gives rise to the pulmonary arteries, aorta, and coronary arteries, with a large ventricular septal defect. The infant has not received prostaglandin E1. Which of the following is the most likely diagnosis?
Answer choices
- ATransposition of the great arteries with an atrial septal defect
- BTotal anomalous pulmonary venous return
- CTetralogy of Fallot with coronary artery anomaly
- DPulmonary atresia with intact ventricular septum
- ETruncus arteriosusCorrect answer
- FDouble outlet right ventricle with pulmonary stenosis
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