Objectives: The study was designed to assess the effect of elapsed time from coronary revascularization (CR) on the benefit of the implantable cardioverter-defibrillator (ICD) and the risk of sudden cardiac death (SCD) in patients with ischemic left ventricular dysfunction. Background: The ICD improves survival in appropriately selected high-risk cardiac patients by 30% to 54%. However, in the Coronary Artery Bypass Graft (CABG)-Patch trial no evidence of improved survival was shown among a similar population of patients in whom an ICD was implanted prophylactically at the time of elective CABG. Methods: The outcome by time from CR was analyzed in 951 patients in whom a revascularization procedure was performed before enrollment in the Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II. Results: The adjusted hazard ratio (HR) of ICD versus conventional therapy was 0.64 (p = 0.01) among patients enrolled more than six months after CR, whereas no survival benefit with ICD therapy was shown among patients enrolled six months or earlier after CR (HR = 1.19; p = 0.76). In the conventional therapy group, the risk of cardiac death increased significantly with increasing time from CR (p for trend = 0.009), corresponding mainly to a six-fold increase in the risk of SCD among patients enrolled more than six months after CR. Conclusions: In patients with ischemic left ventricular dysfunction, the efficacy of ICD therapy after CR is time dependent, with a significant life-saving benefit in patients receiving device implantation more than six months after CR. The lack of ICD benefit when implanted early after CR may be related to a relatively low risk of SCD during this time period. © 2006 American College of Cardiology Foundation.
Goldenberg, I., Moss, A. J., McNitt, S., Zareba, W., Hall, W. J., Andrews, M. L., … Klein, H. U. (2006). Time Dependence of Defibrillator Benefit After Coronary Revascularization in the Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II. Journal of the American College of Cardiology, 47(9), 1811–1817. https://doi.org/10.1016/j.jacc.2005.12.048