Treatment of patients with supraventricular tachyarrhythmias in a medical intensive care unit.

Direct-current cardioversion has a higher success rate than does medical therapy in converting supraventricular tachyarrhythmias to sinus rhythm and should be performed immediately in patients with hemodynamic instability. Hemodynamically stable patients with atrial fibrillation or atrial flutter, a rapid ventricular rate and without preexcitation syndrome should be treated with intravenous beta-adrenergic blocking drugs, amiodarone, verapamil, or diltiazem. In hemodynamically unstable patients with supraventricular tachycardia, intravenous adenosine is the drug of choice.