Arrhythmias USMLE Step 1 Practice Question
A 28-year-old man with a history of intermittent palpitations presents with lightheadedness. Vital signs: BP 118/76 mmHg, HR 165 bpm, RR 18, temp 37.2°C, SpO2 98% on room air. ECG shows irregular wide-complex tachycardia with varying QRS morphology. Prior ECG in sinus rhythm demonstrated a short PR interval and delta waves. Troponin is normal. He denies chest pain. Which pharmacologic agent is most appropriate for acute rate control in this hemodynamically stable patient?
Answer choices
- AVerapamil
- BProcainamideCorrect answer
- CAdenosine
- DDigoxin
- EMetoprolol
- FFlecainide
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