Heart Failure USMLE Step 1 Practice Question
A 3-month-old male with trisomy 21 presents with poor feeding and failure to thrive. Vital signs show HR 156 bpm, RR 48/min, BP 82/56 mmHg, and SpO2 94% on room air. Physical examination reveals a systolic murmur at the left lower sternal border. Chest X-ray demonstrates cardiomegaly with pulmonary congestion. Echocardiography reveals abnormal fusion of the atrioventricular septal region with a common atrioventricular valve. Lung auscultation shows no rales. Which of the following is the most likely diagnosis?
Answer choices
- ATetralogy of Fallot
- BEndocardial cushion defectCorrect answer
- CEbstein anomaly
- DPatent ductus arteriosus
- ECoarctation of the aorta
- FIsolated ventricular septal defect
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