Arrhythmias USMLE Step 1 Practice Question
A 68-year-old man is on postoperative day 3 after coronary artery bypass graft surgery. He develops an irregularly irregular tachycardia with heart rate of 118/min. Vital signs show blood pressure 132/78 mmHg, respiratory rate 20/min, temperature 37.2°C, and SpO2 98% on room air. P waves are not visible on electrocardiography. Troponin is mildly elevated at 0.08 ng/mL. He denies chest pain. He is not currently taking beta-blockers. Which diagnosis is most likely?
Answer choices
- AMobitz II block
- BJunctional escape rhythm
- CVentricular tachycardia
- DAtrial flutter
- EAtrial fibrillationCorrect answer
- FSinus tachycardia with frequent premature atrial contractions
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