Congenital Heart Disease USMLE Step 1 Practice Question
A 3-day-old male born at term presents with cyanosis. Physical examination reveals differential cyanosis, with the face and upper extremities appearing less blue than the lower body and feet. Vital signs include heart rate 158/min, respiratory rate 50/min, blood pressure 62/38 mmHg, and oxygen saturation 91% in the right hand versus 84% in the left foot. A continuous murmur is audible at the left infraclavicular region. Chest X-ray shows normal pulmonary vascular markings without cardiomegaly. Echocardiography demonstrates right-to-left shunting through a patent ductus arteriosus with elevated pulmonary artery pressures exceeding systemic pressures. The infant has not received prostaglandin E1. Which of the following is the most likely diagnosis?
Answer choices
- ATransposition of the great arteries with intact ventricular septum
- BTetralogy of Fallot with severe right ventricular outflow tract obstruction
- CPersistent pulmonary hypertension of the newbornCorrect answer
- DTotal anomalous pulmonary venous return with restrictive atrial septal defect
- EPatent ductus arteriosus with left-to-right shunting and pulmonary edema
- FCoarctation of the aorta with bicuspid aortic valve
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