Temporal Trends in Patient Characteristics and Outcomes Among Medicare Beneficiaries Undergoing Primary Prevention Implantable Cardioverter-Defibrillator Placement in the United States, 2006–2010

Abstract

Background— Contemporary patterns of use and outcomes of implantable cardioverter-defibrillators (ICDs) in community practice settings are not well characterized. We assessed temporal trends in patient characteristics and outcomes among older patients undergoing primary prevention ICD therapy in US hospitals between 2006 and 2010. Methods and Results— Using the National Cardiovascular Data Registry’s ICD Registry, we identified Medicare fee-for-service beneficiaries aged ≥65 years and older with left ventricular ejection fraction ≤35% who underwent primary prevention ICD implantation, including those receiving concomitant cardiac resynchronization therapy between 2006 and 2010 and could be matched to Medicare claims. Outcomes were mortality and hospitalization (all-cause and heart failure) at 180 days, and device-related complications. We used multivariable hierarchical logistic regression to assess temporal trends in outcomes accounting for changes in patient, physician, and hospital characteristics. The cohort included 117 100 patients. Between 2006 and 2010, only modest changes in patient characteristics were noted. Fewer single lead devices and more cardiac resynchronization therapy devices were used over time. Between 2006 and 2010, there were significant improvements in all outcomes, including 6-month all cause mortality (7.1% in 2006, 6.5% 2010; adjusted odds ratio, 0.88; 95% confidence interval, 0.82–0.95), 6-month rehospitalization (36.3% in 2006, 33.7% in 2010; adjusted odds ratio, 0.87; 95% confidence interval, 0.83–0.91), and device-related complications (5.8% in 2006, 4.8% in 2010; adjusted odds ratio, 0.80; 95% confidence interval, 0.74–0.88). Conclusions— The clinical characteristics of this national population of Medicare patients undergoing primary prevention ICD implantation were stable between 2006 and 2010. Simultaneous improvements in outcomes suggest meaningful advances in the care for this patient population.