Arrhythmias USMLE Step 1 Practice Question
A 65-year-old man with recurrent ventricular tachycardia was started on antiarrhythmic therapy. Three months later, he presents with progressive dyspnea, orthopnea, and fatigue. Vital signs show BP 128/82, HR 88, RR 22, SpO2 89% on room air. Chest X-ray reveals bilateral interstitial infiltrates. Laboratory studies show TSH 8.2 mIU/L (elevated), normal ejection fraction on echocardiography, and negative antinuclear antibody. Which antiarrhythmic drug is the most likely cause of these findings?
Answer choices
- AVerapamil
- BDigoxin
- CMetoprolol
- DAmiodaroneCorrect answer
- EAdenosine
- FFlecainide
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