title: Longitudinal study of implantable cardioverter-defibrillators: methods and clinical characteristics of patients receiving implantable cardioverter-defibrillators for primary prevention in contemporary practice.
abstract: BACKGROUND
  Implantable cardioverter-defibrillators (ICDs) are increasingly used for primary prevention after randomized, controlled trials demonstrating that they reduce the risk of death in patients with left ventricular systolic dysfunction. The extent to which the clinical characteristics and long-term outcomes of unselected, community-based patients with left ventricular systolic dysfunction undergoing primary prevention ICD implantation in a real-world setting compare with those enrolled in the randomized, controlled trials is not well characterized. This study is being conducted to address these questions.
  
  
  RESULTS
  The study cohort includes consecutive patients undergoing primary prevention ICD placement between January 1, 2006 and December 31, 2009 in 7 health plans. Baseline clinical characteristics were acquired from the National Cardiovascular Data Registry ICD Registry. Longitudinal data collection is underway, and will include hospitalization, mortality, and resource use from standardized health plan data archives. Data regarding ICD therapies will be obtained through chart abstraction and adjudicated by a panel of experts in device therapy. Compared with the populations of primary prevention ICD therapy randomized, controlled trials, the cohort (n=2621) is on average significantly older (by 2.5-6.5 years), more often female, more often from racial and ethnic minority groups, and has a higher burden of coexisting conditions. The cohort is similar, however, to a national population undergoing primary prevention ICD placement.
  
  
  CONCLUSIONS
  Patients undergoing primary prevention ICD implantation in this study differ from those enrolled in the randomized, controlled trials that established the efficacy of ICDs. Understanding a broad range of health outcomes, including ICD therapies, will provide patients, clinicians, and policy makers with contemporary data to inform decision-making.
authors.affiliation: Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. fred.masoudi@ucdenver.edu
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Masoudi
authors.forename: Alan S
authors.initials: AS
authors.lastname: Go
authors.forename: David J
authors.initials: DJ
authors.lastname: Magid
authors.forename: Andrea E
authors.initials: AE
authors.lastname: Cassidy-Bushrow
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Doris
authors.forename: Frances
authors.initials: F
authors.lastname: Fiocchi
authors.forename: Romel
authors.initials: R
authors.lastname: Garcia-Montilla
authors.forename: Karen A
authors.initials: KA
authors.lastname: Glenn
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Goldberg
authors.forename: Nigel
authors.initials: N
authors.lastname: Gupta
authors.forename: Jerry H
authors.initials: JH
authors.lastname: Gurwitz
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hammill
authors.forename: John J
authors.initials: JJ
authors.lastname: Hayes
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Jackson
authors.forename: Alan
authors.initials: A
authors.lastname: Kadish
authors.forename: Michael
authors.initials: M
authors.lastname: Lauer
authors.forename: Aaron W
authors.initials: AW
authors.lastname: Miller
authors.forename: Deborah
authors.initials: D
authors.lastname: Multerer
authors.forename: Pamela N
authors.initials: PN
authors.lastname: Peterson
authors.forename: Liza M
authors.initials: LM
authors.lastname: Reifler
authors.forename: Kristi
authors.initials: K
authors.lastname: Reynolds
authors.forename: Jane S
authors.initials: JS
authors.lastname: Saczynski
authors.forename: Claudio
authors.initials: C
authors.lastname: Schuger
authors.forename: Param P
authors.initials: PP
authors.lastname: Sharma
authors.forename: David H
authors.initials: DH
authors.lastname: Smith
authors.forename: Mary
authors.initials: M
authors.lastname: Suits
authors.forename: Sue Hee
authors.initials: SH
authors.lastname: Sung
authors.forename: Paul D
authors.initials: PD
authors.lastname: Varosy
authors.forename: Humberto J
authors.initials: HJ
authors.lastname: Vidaillet
authors.forename: Robert T
authors.initials: RT
authors.lastname: Greenlee
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D006760:Hospitalization; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011322:Primary Prevention / Q000379:methods*; D012042:Registries; D012107:Research Design; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000628:therapy*