Congenital Heart Disease USMLE Step 1 Practice Question
A 2-day-old male infant is transferred to the NICU for evaluation of cyanosis and a systolic heart murmur. Birth history is notable for maternal diabetes and the infant has characteristic facial features including micrognathia, short philtrum, and hypertelorism. Vital signs show oxygen saturation of 78% on room air. Physical examination reveals a single loud S2. Chest X-ray demonstrates boot-shaped heart with decreased pulmonary vascular markings. Echocardiography shows a large VSD with rightward deviation of the ventricular septal defect, right ventricular outflow tract obstruction secondary to infundibular stenosis, and a normal aorta that overrides the VSD. Which of the following is the most likely diagnosis?
Answer choices
- ADouble outlet right ventricle
- BTruncus arteriosus
- CTetralogy of FallotCorrect answer
- DTransposition of the great arteries with VSD
- EPulmonary atresia with intact ventricular septum
- FTotal anomalous pulmonary venous return
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