Valvular Heart Disease USMLE Step 1 Practice Question
A 35-year-old man with a history of intravenous drug use presents to the emergency department with a 1-week history of fever, malaise, and dyspnea. Vital signs show temperature 39.1°C, heart rate 118/min, respiratory rate 24/min, and blood pressure 128/82 mmHg. Physical examination reveals a new holosystolic murmur best heard at the left lower sternal border that increases with inspiration. Laboratory studies show WBC 14,500/μL and elevated inflammatory markers. Chest X-ray demonstrates multiple peripheral, wedge-shaped infiltrates. Blood cultures are pending but grow Staphylococcus aureus. Transthoracic echocardiography shows a 12-mm vegetation on a valve with right-to-left flow. The patient denies recent dental work, cardiac surgery, or prosthetic valve placement. Which valve is most likely affected in this patient?
Answer choices
- ATricuspid valveCorrect answer
- BAortic valve
- CMitral valve
- DPulmonary valve
- ELeft main coronary artery ostium
- FEustachian valve
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