Arrhythmias USMLE Step 1 Practice Question
A 58-year-old woman with atrial fibrillation started on sotalol 2 days ago presents with recurrent syncope. Vital signs: BP 92/58, HR 52, RR 18, SpO2 98% on room air. ECG demonstrates QTc interval of 520 ms. Telemetry captures polymorphic ventricular tachycardia with the QRS axis twisting around the baseline. Serum potassium is 3.2 mEq/L. She denies chest pain. Which diagnosis best explains these findings?
Answer choices
- ABrugada syndrome
- BTorsades de pointesCorrect answer
- CMonomorphic ventricular tachycardia
- DMultifocal atrial tachycardia
- EAtrial flutter with variable block
- FLong QT syndrome
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