Arrhythmias USMLE Step 1 Practice Question
A 34-year-old woman on sotalol for atrial fibrillation presents with sudden syncope. Vital signs show BP 88/56 mmHg, HR 160 bpm, RR 22/min, and SpO2 94% on room air. Telemetry reveals polymorphic ventricular tachycardia with QRS complexes twisting around the isoelectric baseline. ECG shows a prolonged QTc interval of 520 ms. She denies palpitations prior to syncope and has no family history of sudden cardiac death. Serum potassium is 3.2 mEq/L. Which diagnosis best explains these findings?
Answer choices
- AAV nodal reentrant tachycardia
- BCardiogenic shock
- CAtrial flutter
- DTorsades de pointesCorrect answer
- EWolff Parkinson White syndrome
- FSotalol-induced ventricular fibrillation
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