Congenital Heart Disease USMLE Step 1 Practice Question
A 7-month-old male presents with episodes of cyanosis worsening during feeding and crying. Parents report the infant instinctively assumes a squatting position during play. Vital signs show HR 145 bpm, RR 38, BP 95/60, SpO2 78% on room air. Examination reveals a harsh systolic ejection murmur at the left sternal border. Chest X-ray demonstrates a "boot-shaped" heart with decreased pulmonary vascular markings. The infant denies recent respiratory infections. Which anatomic abnormalities best explain these findings?
Answer choices
- AAtrial septal defect, tricuspid stenosis, pulmonary edema, and left ventricular hypertrophy
- BEndocardial cushion defect with mitral atresia
- CAortic stenosis, atrial septal defect, left ventricular hypertrophy, and PDA
- DTransposed great vessels, PDA, and coarctation
- EVentricular septal defect, overriding aorta, right ventricular outflow obstruction, and right ventricular hypertrophyCorrect answer
- FPulmonary stenosis, atrial septal defect, right atrial enlargement, and pulmonary vascular congestion
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