Glatter K, Yang Y, Chatterjee K, Modin G, Cheng J, Kayser S, Scheinman M M
Cardiovascular Research Institute and Section of Cardiac Electrophysiology, University of California, San Francisco 94143-1354, USA.
Circulation. 2001 Jan 16;103(2):253-7. doi: 10.1161/01.cir.103.2.253.
Ibutilide is a class III drug that is used for the cardioversion of atrial arrhythmias, but it can cause torsade de pointes. Amiodarone also prolongs the QT interval but rarely causes torsade de pointes. There are no studies in which the concomitant use of the 2 agents was examined. The purpose of the present study was to assess the efficacy and safety of cardioversion with combination therapy in patients with atrial fibrillation or flutter.
The study included 70 patients who were treated with long-term oral amiodarone and were referred for elective cardioversion of atrial fibrillation (57 of 70, 81%) or flutter (13 of 70, 19%). Patients were taking amiodarone (153+/-259 days, mean+/-SD) and were administered 2 mg intravenous ibutilide. Left ventricular ejection fraction was measured with echocardiography. The QT intervals were measured on 12-lead ECG. Fifty-five patients (79%) had structural heart disease. Patients were in arrhythmia for 196+/-508 days before cardioversion, with a left ventricular ejection fraction of 50+/-11%. In patients with atrial fibrillation, 22 (39%) of 57 and 7 (54%) of 13 patients with flutter converted within 30 minutes of infusion. Thirty-nine patients who did not convert after ibutilide were treated with electrical cardioversion, and 35 (90%) of 39 patients were successfully converted. The QT intervals were further prolonged after ibutilide for the group from 371+/-61 to 479+/-92 ms (P:<0.001). There was 1 episode of nonsustained torsade de pointes (1 of 70, 1.4%) after ibutilide.
The use of ibutilide converted 54% of patients with atrial flutter and 39% of patients with atrial fibrillation who were treated with long-term amiodarone. Despite QT-interval prolongation after ibutilide, only 1 episode of torsade de pointes occurred. Our observations suggest that combination therapy may be a useful cardioversion method for chronic atrial fibrillation or flutter.
伊布利特是一种III类药物，用于心房心律失常的转复，但它可引起尖端扭转型室速。胺碘酮也可延长QT间期，但很少引起尖端扭转型室速。尚无关于这两种药物联合使用的研究。本研究的目的是评估联合治疗对心房颤动或心房扑动患者转复的有效性和安全性。
本研究纳入70例长期口服胺碘酮并因心房颤动（70例中的57例，81%）或心房扑动（70例中的13例，19%）接受择期转复治疗的患者。患者正在服用胺碘酮（153±259天，均值±标准差），并静脉给予2mg伊布利特。用超声心动图测量左心室射血分数。在12导联心电图上测量QT间期。55例患者（79%）有结构性心脏病。患者在转复前心律失常持续196±508天；左心室射血分数为50±11%。在心房颤动患者中，57例中的22例（39%）和13例心房扑动患者中的7例（54%）在输注后30分钟内转复。39例伊布利特治疗后未转复的患者接受了电转复，39例患者中的35例（90%）成功转复。伊布利特给药后，该组的QT间期从371±61ms进一步延长至479±92ms（P<0.001）。伊布利特给药后发生1次非持续性尖端扭转型室速（70例中的1例，1.4%）。
伊布利特的使用使长期服用胺碘酮治疗的心房扑动患者中有54%、心房颤动患者中有39%转复。尽管伊布利特给药后QT间期延长，但仅发生1次尖端扭转型室速。我们的观察结果提示，联合治疗可能是慢性心房颤动或心房扑动的一种有用的转复方法。
