Connolly S J, Hallstrom A P, Cappato R, Schron E B, Kuck K H, Zipes D P, Greene H L, Boczor S, Domanski M, Follmann D, Gent M, Roberts R S
Hamilton Health Sciences Corporation, Hamilton, ON, Canada.
Eur Heart J. 2000 Dec;21(24):2071-8. doi: 10.1053/euhj.2000.2476.
Three randomized trials of implantable cardioverter defibrillator (ICD) therapy vs medical treatment for the prevention of death in survivors of ventricular fibrillation or sustained ventricular tachycardia have been reported with what might appear to be different results. The present analysis was performed to obtain the most precise estimate of the efficacy of the ICD, compared to amiodarone, for prolonging survival in patients with malignant ventricular arrhythmia.
Individual patient data from the Antiarrhythmics vs Implantable Defibrillator (AVID) study, the Cardiac Arrest Study Hamburg (CASH) and the Canadian Implantable Defibrillator Study (CIDS) were merged into a master database according to a pre-specified protocol. Proportional hazard modelling of individual patient data was used to estimate hazard ratios and to investigate subgroup interactions. Fixed effect meta-analysis techniques were also used to evaluate treatment effects and to assess heterogeneity across studies. The classic fixed effects meta-analysis showed that the estimates of ICD benefit from the three studies were consistent with each other (P heterogeneity=0.306). It also showed a significant reduction in death from any cause with the ICD; with a summary hazard ratio (ICD:amiodarone) of 0.72 (95% confidence interval 0.60, 0.87;P=0.0006). For the outcome of arrhythmic death, the hazard ratio was 0.50 (95% confidence interval 0.37, 0.67;P<0.0001). Survival was extended by a mean of 4.4 months by the ICD over a follow-up period of 6 years. Patients with left ventricular ejection fraction < or = 35% derived significantly more benefit from ICD therapy than those with better preserved left ventricular function. Patients treated before the availability of non-thoracotomy ICD implants derived significantly less benefit from ICD therapy than those treated in the non-thoracotomy era.
Results from the three trials of the ICD vs amiodarone are consistent with each other. There is a 28% reduction in the relative risk of death with the ICD that is due almost entirely to a 50% reduction in arrhythmic death.
已有三项关于植入式心脏复律除颤器（ICD）治疗与药物治疗预防心室颤动或持续性室性心动过速幸存者死亡的随机试验报告，但其结果似乎有所不同。本分析旨在获得与胺碘酮相比，ICD延长恶性室性心律失常患者生存期疗效的最精确估计。
根据预先指定的方案，将抗心律失常药物与植入式除颤器（AVID）研究、汉堡心脏骤停研究（CASH）和加拿大植入式除颤器研究（CIDS）的个体患者数据合并到一个主数据库中。使用个体患者数据的比例风险模型来估计风险比并研究亚组间的相互作用。固定效应荟萃分析技术也用于评估治疗效果并评估各研究间的异质性。经典的固定效应荟萃分析表明，三项研究中ICD获益的估计彼此一致（P异质性 = 0.306）。该分析还表明，ICD可显著降低任何原因导致的死亡；汇总风险比（ICD：胺碘酮）为0.72（95%置信区间0.60，0.87；P = 0.0006）。对于心律失常性死亡结局，风险比为0.50（95%置信区间0.37，0.67；P < 0.0001）。在6年的随访期内，ICD使生存期平均延长4.4个月。左心室射血分数≤35%的患者从ICD治疗中获得的益处明显多于左心室功能保存较好的患者。在非开胸ICD植入可用之前接受治疗的患者从ICD治疗中获得的益处明显少于在非开胸时代接受治疗的患者。
ICD与胺碘酮的三项试验结果彼此一致。ICD使死亡相对风险降低28%，这几乎完全归因于心律失常性死亡降低50%。
