BACKGROUND: Little is known about factors that influence survival and complications following ICD implantation in routine clinical practice. We examined patient and implanting physician factors associated with outcomes of implantable cardioverter-defibrillator (ICD) therapy in Medicare beneficiaries from 2002 through 2005. METHODS AND RESULTS: We limited this analysis to patients aged 65 or older with Medicare fee-for-service coverage who received an ICD between January 2002 and September 2005. The main outcome measures are time to post-procedural complications within 90 days and 1-year mortality. During the study period, 8581 patients had an ICD implanted by 1959 physicians. The number of procedures increased from 1644 in 2002 to 2374 in the first three quarters of 2005. The overall complication rate declined from 18.8% in 2002 to 14.2% in 2005 (P < .001). Factors independently associated with an increased hazard of complications include chronic lung disease, dementia, renal disease, implantation by a thoracic surgeon and implantation with removal/replacement. History of congestive heart failure, outpatient implantation and more recent years of ICD implantation were associated with a lower risk of complications (P < .05 for all factors). From 2002 to 2005, we observed a decline in 1-year mortality (P < .001). CONCLUSIONS: We observed an appreciable increase in the number of ICD implants which was associated with a significant decrease in the rate of complications and 1-year mortality. We identified factors associated with an increased risk of mortality and post-procedural complications that may support more nuanced treatment decisions than are currently possible

automatic medline import