Congenital Heart Disease USMLE Step 1 Practice Question
A cyanotic neonate presents at 6 hours of life with oxygen saturation 78% on room air, heart rate 165 bpm, and respiratory rate 58/min. The mother took lithium throughout pregnancy for bipolar disorder management. Echocardiography demonstrates apical displacement of dysplastic tricuspid valve leaflets into the right ventricle with severe regurgitation. Chest X-ray shows cardiomegaly and decreased pulmonary vascular markings. The infant has no audible murmur. Which maternal medication is most strongly associated with this cardiac defect?
Answer choices
- AValproic acid
- BLithiumCorrect answer
- CMethimazole
- DWarfarin
- EIsotretinoin
- FPhenytoin
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