A 55-year-old woman with hypertension and two-vessel coronary artery bypass graft presents with increasing dyspnea and palpitations. EKG shows atrial flutter with 2:1 AV block and echocardiogram shows normal LV function. Which therapy is most appropriate?

A 55-year-old woman with hypertension and two-vessel coronary artery bypass graft presents with increasing dyspnea and palpitations. EKG shows atrial flutter with 2:1 AV block and echocardiogram shows normal LV function. Which therapy is most appropriate?

• A. IV ibutilide after 4 weeks of anticoagulation with warfarin
• B. IV ibutilide alone
• C. IV quinidine after 4 weeks of anticoagulation with warfarin
• D. IV quinidine alone

Answer: (B)

Atrial flutter can often be treated effectively with rapid chemical cardioversion when the patient is stable and the flutter is of recent onset. IV ibutilide, a class III antiarrhythmic, is specifically used to convert recent-onset atrial flutter or fibrillation to sinus rhythm quickly while the patient is under continuous ECG monitoring. In this scenario, the patient is hemodynamically stable with normal LV function, so attempting immediate pharmacologic conversion with ibutilide is appropriate. It avoids delaying rhythm restoration with prior anticoagulation unless the duration of flutter is known to be longer than 48 hours or uncertain; in those cases, more careful planning with anticoagulation or TEE-guided cardioversion would be considered. Why the other approaches aren’t as suitable here: waiting 4 weeks of warfarin before attempting conversion unnecessarily delays relief of symptoms and rhythm restoration; quinidine is less effective for acute conversion and carries proarrhythmic risk, particularly in patients with structural heart disease. Therefore, intravenous ibutilide alone is the best option to restore sinus rhythm promptly in this patient.

Atrial flutter can often be treated effectively with rapid chemical cardioversion when the patient is stable and the flutter is of recent onset. IV ibutilide, a class III antiarrhythmic, is specifically used to convert recent-onset atrial flutter or fibrillation to sinus rhythm quickly while the patient is under continuous ECG monitoring.

In this scenario, the patient is hemodynamically stable with normal LV function, so attempting immediate pharmacologic conversion with ibutilide is appropriate. It avoids delaying rhythm restoration with prior anticoagulation unless the duration of flutter is known to be longer than 48 hours or uncertain; in those cases, more careful planning with anticoagulation or TEE-guided cardioversion would be considered.

Why the other approaches aren’t as suitable here: waiting 4 weeks of warfarin before attempting conversion unnecessarily delays relief of symptoms and rhythm restoration; quinidine is less effective for acute conversion and carries proarrhythmic risk, particularly in patients with structural heart disease. Therefore, intravenous ibutilide alone is the best option to restore sinus rhythm promptly in this patient.