David F Katz1, Pamela Peterson2, Ryan T Borne3, Jarrod Betz4, Sana M Al-Khatib5, Paul D Varosy6, Yongfei Wang7, Jonathan C Hsu8, Kurt S Hoffmayer9, Ryan T Kipp9, Carolina Malta Hansen5, Mintu P Turakhia10, Frederick A Masoudi3. 1. Division of Cardiology, University of Colorado, Denver, Colorado; Colorado Cardiovascular Outcomes Research Group, Denver, Colorado. Electronic address: David.Katz@UCDenver.edu. 2. Division of Cardiology, University of Colorado, Denver, Colorado; Colorado Cardiovascular Outcomes Research Group, Denver, Colorado; Denver Health Medical Center, Denver, Colorado. 3. Division of Cardiology, University of Colorado, Denver, Colorado; Colorado Cardiovascular Outcomes Research Group, Denver, Colorado. 4. Department of Medicine, University of Colorado, Denver, Colorado. 5. Division of Cardiology, Duke University, Durham, North Carolina. 6. Division of Cardiology, University of Colorado, Denver, Colorado; Colorado Cardiovascular Outcomes Research Group, Denver, Colorado; Eastern Colorado VA Healthcare System, Denver, Colorado. 7. Yale University and Center of Outcomes Research and Evaluation, New Haven, Connecticut. 8. Division of Cardiology, University of California San Diego, San Diego, California. 9. Division of Cardiology, University of Wisconsin, Madison, Wisconsin. 10. VA Palo Alto Health Care System, Palo Alto, California; Division of Cardiology, Stanford University, Palo Alto, California.
Abstract
OBJECTIVES: This study sought to define the characteristics and risks of death of patients receiving a physician-designated secondary prevention implantable cardioverter-defibrillator (ICD) in contemporary clinical practice. BACKGROUND: Data on utilization and outcomes of ICDs for the secondary prevention of sudden cardiac death (SCD) are limited. METHODS: Patients enrolled in the National Cardiovascular Data Registry's (NCDR) ICD Registry from 2006 to 2009 with a physician-designated secondary prevention indication for ICD implantation were identified and linked to the Social Security Death Master File. Those patients with a history either of tachycardic arrest or sustained ventricular tachycardia (SCD/VT) or of syncope without SCD/VT were included. Kaplan-Meier survival analysis was used to assess mortality. Cox proportional hazards survival modeling was used to assess the risk of death in these groups, adjusting for patient characteristics. RESULTS: In the study cohort of 46,685 patients (mean age 66 ± 14 years, 73.5% male, 85% white), 78% had SCD/VT and 22% had syncope. Overall mortality was 10.4% at 1 year and 16.4% at 2 years. Compared with patients having SCD/VT, the adjusted hazard of death at 1 year was lower in the patients having syncope (hazard ratio: 0.89; 95% confidence interval: 0.83 to 0.96) but was not significantly different by 2 years (hazard ratio: 0.96; 95% confidence interval: 0.90 to 1.01). CONCLUSIONS: Nearly 9 of 10 patients receiving a secondary prevention ICD in clinical practice are alive 1 year after implantation. The risk of death varies by indication and is highest among patients who survive SCD or sustained VT in the first year after device implantation.
OBJECTIVES: This study sought to define the characteristics and risks of death of patients receiving a physician-designated secondary prevention implantable cardioverter-defibrillator (ICD) in contemporary clinical practice. BACKGROUND: Data on utilization and outcomes of ICDs for the secondary prevention of sudden cardiac death (SCD) are limited. METHODS:Patients enrolled in the National Cardiovascular Data Registry's (NCDR) ICD Registry from 2006 to 2009 with a physician-designated secondary prevention indication for ICD implantation were identified and linked to the Social Security Death Master File. Those patients with a history either of tachycardic arrest or sustained ventricular tachycardia (SCD/VT) or of syncope without SCD/VT were included. Kaplan-Meier survival analysis was used to assess mortality. Cox proportional hazards survival modeling was used to assess the risk of death in these groups, adjusting for patient characteristics. RESULTS: In the study cohort of 46,685 patients (mean age 66 ± 14 years, 73.5% male, 85% white), 78% had SCD/VT and 22% had syncope. Overall mortality was 10.4% at 1 year and 16.4% at 2 years. Compared with patients having SCD/VT, the adjusted hazard of death at 1 year was lower in the patients having syncope (hazard ratio: 0.89; 95% confidence interval: 0.83 to 0.96) but was not significantly different by 2 years (hazard ratio: 0.96; 95% confidence interval: 0.90 to 1.01). CONCLUSIONS: Nearly 9 of 10 patients receiving a secondary prevention ICD in clinical practice are alive 1 year after implantation. The risk of death varies by indication and is highest among patients who survive SCD or sustained VT in the first year after device implantation.