Congenital Heart Disease USMLE Step 1 Practice Question
A 6-month-old boy presents with poor feeding and failure to thrive. Vital signs show HR 145 bpm, BP 95/55 mmHg with widened pulse pressure, RR 52/min, and SpO2 92% on room air. Physical examination reveals a continuous 'machinery' murmur at the left infraclavicular area with bounding femoral pulses. Chest X-ray demonstrates pulmonary edema. Echocardiography shows left atrial enlargement. Cyanosis is absent. Which diagnosis is most likely?
Answer choices
- AAortic stenosis
- BVentricular septal defect
- CPatent ductus arteriosusCorrect answer
- DAtrial septal defect
- ECoarctation of the aorta
- FTetralogy of Fallot
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.