Congenital Heart Disease USMLE Step 1 Practice Question
A 4-year-old girl is brought to the emergency department after a syncopal episode during soccer practice. Her mother reports a 6-month history of exercise-induced dyspnea and chest pain with activity. She denies recent illness, fever, or orthopnea. Vital signs: BP 115/70 mmHg, HR 108/min, RR 24/min, SpO2 98% on room air. Physical examination reveals a prominent apical impulse, a harsh systolic ejection murmur best heard at the left lower sternal border that increases with standing and decreases with squatting, and a normal S2 with no diastolic murmur. Echocardiography shows asymmetric septal hypertrophy with systolic anterior motion of the mitral valve and left ventricular outflow tract obstruction with a peak gradient of 68 mmHg. Which of the following is the most likely diagnosis?
Answer choices
- AAortic stenosis
- BDilated cardiomyopathy
- CHypertrophic cardiomyopathyCorrect answer
- DRestrictive cardiomyopathy
- EVentricular septal defect with aortic regurgitation
- FPulmonary stenosis
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