title: Dual-chamber implantable cardioverter-defibrillator selection is associated with increased complication rates and mortality among patients enrolled in the NCDR implantable cardioverter-defibrillator registry.
abstract: OBJECTIVE
  The aim of this study was to compare single- versus dual-chamber implantable cardioverter-defibrillator (ICD) implantation and complication rates in a large, real-world population.
  
  
  BACKGROUND
  The majority of patients enrolled in ICD efficacy trials received single-chamber devices. Although dual-chamber ICDs offer theoretical advantages over single-chamber defibrillators, the clinical superiority of dual-chamber models has not been conclusively proven, and they may increase complications.
  
  
  METHODS
  The National Cardiovascular Data Registry ICD Registry was used to examine the association between baseline characteristics and device selection in 104,049 patients receiving single- and dual-chamber ICDs between January 1, 2006, and December 31, 2007. A longitudinal cohort design was then used to determine in-hospital complication rates.
  
  
  RESULTS
  Dual-chamber devices were implanted in 64,489 patients (62%). Adverse events were more frequent with dual-chamber than with single-chamber device implantation (3.17% vs. 2.11%, p < 0.001), as was the rate of in-hospital mortality (0.40% vs. 0.23%, p < 0.001). After adjusting for demographics, medical comorbidities, diagnostic test data, and ICD indication, the odds of any complication (odds ratio: 1.40; 95% confidence interval: 1.28 to 1.52; p < 0.001) and in-hospital mortality (odds ratio: 1.45; 95% confidence interval: 1.20 to 1.74; p < 0.001) were increased with dual-chamber versus single-chamber ICD implantation.
  
  
  CONCLUSIONS
  In this large, multicenter cohort of patients, dual-chamber ICD use was common. Dual-chamber device implantation was associated with increases in periprocedural complications and in-hospital mortality compared with single-chamber defibrillator selection.
authors.affiliation: Division of Cardiology, University of California-San Francisco, CA, USA.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Dewland
authors.forename: Cara N
authors.initials: CN
authors.lastname: Pellegrini
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Wang
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Marcus
authors.forename: Edmund
authors.initials: E
authors.lastname: Keung
authors.forename: Paul D
authors.initials: PD
authors.lastname: Varosy
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation / Q000401:mortality; D012042:Registries; D014481:United States / Q000453:epidemiology