Vascular Disease USMLE Step 1 Practice Question
A 42-year-old man with no significant past medical history presents to the emergency department with acute substernal chest pain, diaphoresis, and dyspnea. Vital signs show BP 145/92 mmHg, HR 102 bpm, and RR 18. An ECG demonstrates ST-segment elevation in leads V1–V4. Emergent cardiac catheterization reveals an acute thrombus occluding the proximal left anterior descending artery with no evidence of significant atherosclerotic plaque. Laboratory evaluation shows elevated troponin I (8.2 ng/mL), elevated creatine kinase-MB, platelet count 185,000/μL, and normal partial thromboplastin time. Subsequent thrombophilia workup is positive for anticardiolipin antibodies and lupus anticoagulant. Which of the following is the most likely diagnosis?
Answer choices
- ASpontaneous coronary artery dissection (SCAD)
- BAcute myocarditis with secondary coronary thrombosis
- CAntiphospholipid syndromeCorrect answer
- DCoronary vasospasm (Prinzmetal angina) with coronary thrombosis
- EAcute thrombotic thrombocytopenic purpura with coronary involvement
- FType 2 myocardial infarction secondary to demand ischemia
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