Kowey P R, Levine J H, Herre J M, Pacifico A, Lindsay B D, Plumb V J, Janosik D L, Kopelman H A, Scheinman M M
Lankenau Hospital and Medical Research Center, Wynnewood, PA 19096, USA.
Circulation. 1995 Dec 1;92(11):3255-63. doi: 10.1161/01.cir.92.11.3255.
After several days of loading, oral amiodarone, a class III antiarrhythmic, is highly effective in controlling ventricular tachyarrhythmias; however, the delay in onset of activity is not acceptable in patients with immediately life-threatening arrhythmias. Therefore, an intravenous form of therapy is advantageous. This study was designed to compare the safety and efficacy of a high and a low dose of intravenous amiodarone with bretylium, the only approved class III antiarrhythmic agent.
A total of 302 patients with refractory, hemodynamically destabilizing ventricular tachycardia or ventricular fibrillation were enrolled in this double-blind trial at 82 medical centers in the United States. They were randomly assigned to therapy with intravenous bretylium (4.7 g) or intravenous amiodarone administered in a high dose (1.8 g) or a low dose (0.2 g). The primary analysis, arrhythmia event rate during the first 48 hours of therapy, showed comparable efficacy between the bretylium group and the high-dose (1000 mg/24 h) amiodarone group that was greater than that of the low-dose (125 mg/24 h) amiodarone group. Similar results were obtained in the secondary analyses of time to first event and the proportion of patients requiring supplemental infusions. Overall mortality in the 48-hour double-blind period was 13.6% and was not significantly different among the three treatment groups. Significantly more patients treated with bretylium had hypotension compared with the two amiodarone groups. More patients remained on the 1000-mg amiodarone regimen than on the other regimens.
Bretylium and amiodarone appear to have comparable efficacies for the treatment of highly malignant ventricular arrhythmias. Bretylium use, however, may be limited by a high incidence of hypotension.
经过数天的负荷给药后，Ⅲ类抗心律失常药物口服胺碘酮在控制室性快速心律失常方面非常有效；然而，对于有即刻危及生命的心律失常的患者，其起效延迟是不可接受的。因此，静脉给药形式的治疗具有优势。本研究旨在比较高剂量和低剂量静脉胺碘酮与溴苄铵（唯一被批准的Ⅲ类抗心律失常药物）的安全性和有效性。
在美国82个医学中心，共有302例难治性、血流动力学不稳定的室性心动过速或心室颤动患者参加了这项双盲试验。他们被随机分配接受静脉注射溴苄铵（4.7 g）或高剂量（1.8 g）或低剂量（0.2 g）静脉胺碘酮治疗。主要分析为治疗的前48小时内心律失常事件发生率，结果显示溴苄铵组与高剂量（1000 mg/24 h）胺碘酮组疗效相当，且均优于低剂量（125 mg/24 h）胺碘酮组。在首次事件发生时间和需要补充输注的患者比例的次要分析中也得到了类似结果。48小时双盲期的总死亡率为13.6%，三个治疗组之间无显著差异。与两个胺碘酮组相比，接受溴苄铵治疗的患者发生低血压的明显更多。与其他治疗方案相比，更多患者维持1000 mg胺碘酮治疗方案。
溴苄铵和胺碘酮在治疗高度恶性室性心律失常方面似乎具有相当的疗效。然而，使用溴苄铵可能会因低血压发生率高而受到限制。
