Arrhythmias USMLE Step 1 Practice Question
A 64-year-old man with hypertension presents with substernal chest pain. Vital signs: BP 98/62, HR 48, RR 14, Temp 37°C, SpO2 98%. ECG shows inferior ST elevation with PR prolongation. Troponin is elevated at 2.8 ng/mL. He denies dyspnea. He takes lisinopril daily. Which coronary artery was most likely involved in the ischemia causing these conduction abnormalities?
Answer choices
- ADiagonal branch
- BRight coronary arteryCorrect answer
- CLeft circumflex artery
- DLeft anterior descending artery
- EObtuse marginal artery
- FLeft main coronary artery
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