Arrhythmias USMLE Step 1 Practice Question
A 22-year-old woman develops sudden palpitations while studying. Vitals: BP 118/76, HR 190, RR 18, Temp 37°C, SpO2 98% on room air. She remains hemodynamically stable with normal mental status. ECG reveals a regular narrow-complex tachycardia at 190 bpm with no visible delta waves. Serum electrolytes and troponin are normal. Vagal maneuvers and adenosine-resistant attempts fail to terminate the episode. Which medication most effectively acutely terminates this arrhythmia?
Answer choices
- AProcainamide
- BEpinephrine
- CAtropine
- DMagnesium sulfate
- EAdenosineCorrect answer
- FVerapamil
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