Arrhythmias USMLE Step 1 Practice Question
A 75-year-old man with hypertension and no prior cardiac history presents with acute palpitations and dyspnea. Vital signs: BP 78/46 mm Hg, HR 160/min, RR 28/min, SpO2 88% on room air. ECG reveals atrial fibrillation with rapid ventricular response. Troponin is normal. Chest X-ray shows mild pulmonary edema without acute coronary findings. He denies chest pain. Which of the following is the best next step in management?
Answer choices
- AProcainamide infusion
- BObservation only
- COral metoprolol
- DImmediate synchronized cardioversionCorrect answer
- EIntravenous adenosine
- FIntravenous diltiazem for rate control
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