Congenital Heart Disease USMLE Step 1 Practice Question
A 6-week-old premature infant born at 28 weeks presents with worsening respiratory distress and signs of congestive heart failure. Vital signs: HR 165/min, RR 58/min, BP 58/32 mmHg, SpO2 88% on supplemental oxygen. Auscultation reveals a continuous "machinery" murmur. Chest X-ray shows pulmonary edema and cardiomegaly. The mother reports taking indomethacin for migraines throughout pregnancy. No cyanosis is noted. Which diagnosis best explains these findings?
Answer choices
- APatent ductus arteriosusCorrect answer
- BTetralogy of Fallot
- CVentricular septal defect
- DCoarctation of the aorta
- EAtrial septal defect
- FTransposition of the great arteries
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