Valvular Heart Disease USMLE Step 1 Practice Question
A 32-year-old woman with a 6-year history of systemic lupus erythematosus (SLE) presents to the emergency department with a 2-week history of progressive dyspnea, low-grade fever (38.1°C), and malaise. On cardiovascular examination, a new early diastolic decrescendo murmur is heard at the left sternal border. Transthoracic echocardiography reveals small, friable vegetations on the aortic valve leaflets with mild aortic regurgitation and preserved left ventricular ejection fraction (58%). Blood cultures obtained on admission and repeated 48 hours later are negative. Serum complement levels are low, and anti-dsDNA antibodies are elevated. Chest radiography shows no pulmonary infiltrates. Which of the following is the most likely diagnosis?
Answer choices
- AAcute bacterial endocarditis with Enterococcus faecalis
- BLibman-Sacks endocarditisCorrect answer
- CFungal endocarditis secondary to disseminated candidiasis
- DMarantic endocarditis associated with underlying malignancy
- EAntiphospholipid syndrome with valve thrombosis
- FRheumatic heart disease with acute rheumatic fever
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.