Congenital Heart Disease USMLE Step 1 Practice Question
A 9-year-old girl presents with progressive exercise intolerance and dyspnea on exertion. Vital signs show HR 98 bpm, BP 110/68 mmHg, RR 18, SpO2 98% on room air. Cardiac examination reveals a midsystolic ejection murmur at the left upper sternal border with fixed split S2. Echocardiography demonstrates a 12-mm ostium secundum defect in the fossa ovalis region with left-to-right shunting. Chest X-ray shows normal heart size without pulmonary edema. Which of the following is the most likely diagnosis?
Answer choices
- APatent foramen ovale
- BCoarctation of the aorta
- CPulmonic valve stenosis
- DAtrial septal defect of the secundum typeCorrect answer
- EVentricular septal defect
- FPartial anomalous pulmonary venous return
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