Congenital Heart Disease USMLE Step 1 Practice Question
A 1-day-old male infant born at term presents to the neonatal intensive care unit with severe cyanosis and respiratory distress. Vital signs show heart rate 168/min, respiratory rate 70/min, oxygen saturation 76% on room air, and blood pressure 98/62 mmHg in the right arm and 58/38 mmHg in the left arm. Physical examination reveals diminished femoral pulses bilaterally, a normal S2, and no murmur appreciated on auscultation. Chest radiograph shows a '3-sign' appearance of the aorta with pulmonary edema. The ductus arteriosus remains patent on echocardiography. Which of the following is the most likely diagnosis?
Answer choices
- AHypoplastic left heart syndrome with right-to-left shunting across the foramen ovale
- BCoarctation of the aorta with ductal-dependent systemic circulationCorrect answer
- CInterrupted aortic arch with associated chromosome 22q11 deletion
- DCritical aortic stenosis with left ventricular dysfunction
- ETransposition of the great arteries with patent ductus arteriosus
- FPatent ductus arteriosus with pulmonary hypertension and right-to-left shunting
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