Evaluation of Early Complications Related to De Novo Cardioverter Defibrillator Implantation Insights From the Ontario ICD Database

Objectives This study examined the predictors of early complications after defibrillator implantation. Background Although implantable cardioverter-defibrillators are widely used, predictors of procedural complications and the consequences of these events have not been determined. Methods In a prospective, multicenter, population-based clinical outcomes registry of all newly implanted defibrillator patients at 18 centers in Ontario, Canada, we examined 45-day complications and all-cause mortality from February 2007 to May 2009. Complications were determined longitudinally and were categorized as direct implantrelated or indirect events. Results Among 3,340 patients (mean age 63.8 +/- 12.5 years, 78.5% men), major complications occurred in 4.1% of de novo procedures. Compared with those undergoing a single-chamber device, implantation of a cardiac resynchronization defibrillator (adjusted hazard ratio [ HR]: 2.17, 95% confidence interval [ CI]: 1.38 to 3.43, p < 0.001) or dual-chamber device (adjusted HR: 1.82, 95% CI: 1.19 to 2.79, p = 0.006) was associated with increased risk of major complications. Major complications were increased in women (adjusted HR: 1.49, 95% CI: 1.02 to 2.16, p = 0.037) and when left ventricular end-systolic dimension exceeded 45 mm (adjusted HR: 1.54, 95% CI: 1.08 to 2.20, p = 0.018). Major complications (excluding death) occurring early after defibrillator implantation were associated with increased adjusted risk of subsequent death up to 180 days after defibrillator implant (adjusted HR: 3.70, 95% CI: 1.64 to 8.33, p = 0.002). Direct implant-related complications were associated with increased risk of early death (adjusted HR: 24.89, p = 0.01), whereas indirect clinical complications conferred increased risk of near-term death (adjusted HR: 12.35, p = 0.001) after defibrillator implantation. Conclusions Complications after de novo defibrillator implantation were strongly associated with device type. Major complications were associated with increased risk of mortality. (J Am Coll Cardiol 2010; 55: 774-82) (C) 2010 by the American College of Cardiology Foundation