Abstract 16941: Device Therapies Among Patients Receiving Primary Prevention Implantable Cardioverter Defibrillators (ICDs): Insights From the Cardiovascular Research Network Longitudinal Study of ICDs
Introduction: Primary prevention implantable cardioverter defibrillators (ICDs) reduce mortality in select patients with left ventricular systolic dysfunction (LVSD). The occurrence of device therapies after ICD implantation in contemporary clinical practice is not well described, especially in patient subgroups designated in the Centers for Medicare and Medicaid Services (CMS) 2005 Coverage with Evidence Development (CED).
Methods: The Longitudinal Study of ICDs assessed rates and correlates of device therapies (overall and those requiring shock) up to 3 years post-implant among 2540 patients with LVSD receiving first-time primary prevention ICDs in 7 US health care systems from 2006-2009. Implant data from the National Cardiovascular Data Registry ICD Registry were linked to electronic longitudinal health care system data and a novel centrally adjudicated repository of device therapies abstracted from medical records. Proportional hazard models evaluated associations with device therapies by appropriateness, adjusted for demographic and clinical factors.
Results: Subjects were 26% women, 35% <65 years old, and 59% non-Hispanic white. Over a mean 26 months, 738 (29.1%) received at least 1 therapy (median 2). Estimated 3-year risk of any device therapy was 36% (24% appropriate, 12% inappropriate); for therapy requiring shock, corresponding values were 24%, 14%, 9%. The rate of appropriate therapy was higher in men than women (adjusted hazard ratio 1.84, 95% confidence interval 1.43-2.35). The rate of inappropriate therapy was higher for subjects <65 than for those >=65 years (1.40, 1.04-1.88), and lower among 2009 implants compared to 2006 (0.66, 0.46-0.95). Regarding the 3 CMS CED patient subgroups, neither ejection fraction nor heart failure symptom severity was associated with device therapy; for LVSD etiology, the rate of inappropriate therapy was nominally but not significantly higher among subjects with non-ischemic cardiomyopathy of < 9 months duration (1.38, 0.88-2.18).
Conclusions: In a representative cohort of primary prevention ICD patients in usual care, rates of device therapies were somewhat lower than in landmark trials, differed by some patient characteristics, but did not differ meaningfully for CMS CED subgroups.
Author Disclosures: R.T. Greenlee: None. A.S. Go: None. D.J. Magid: None. P.N. Peterson: None. A.E. Cassidy-Bushrow: None. C. Gaber: None. R. Garcia-Montilla: None. K.A. Glenn: None. N. Gupta: Research Grant; Significant; St. Jude, Medtronic, Boston Scientific. J.H. Gurwitz: None. S.C. Hammill: None. J.J. Hayes: None. A. Kadish: None. D.D. McManus: None. D. Multerer: None. J. Powers: None. L.M. Reifler: None. K. Reynolds: Research Grant; Significant; Amgen Inc., CSL Behring, iRhythm. C. Schuger: None. P.P. Sharma: None. D.H. Smith: None. M. Suits: None. S. Sung: None. P.D. Varosy: None. H.J. Vidaillet: None. F.A. Masoudi: Other; Significant; American College of Cardiology.
- © 2015 by American Heart Association, Inc.