Dual-chamber defibrillators reduce clinically significant adverse events compared with single-chamber devices: results from the DATAS (Dual chamber and Atrial Tachyarrhythmias Adverse events Study) trial

Europace. 2008 May;10(5):528-35. doi: 10.1093/europace/eun072. Epub 2008 Apr 7.


Aims: This randomized trial evaluated clinically significant adverse events (CSAEs), in patients implanted with dual-chamber (DC) vs. single-chamber (SC) implantable cardioverter defibrillator (ICD). DC-ICD had atrial tachyarrhythmia (AT) therapy capabilities. Strict programming recommendations were reinforced.

Methods and results: Patients with conventional SC-ICD indication were randomized to DC-ICD, SC-ICD, or a DC-ICD programmed as an SC-ICD (SC-simulated) and followed for 16 months. Patients in the DC and SC-simulated groups crossed over after 8 months. The primary endpoint was a composite of CSAE: all-cause mortality; invasive intervention; hospitalization (> 24 h) for cardiovascular causes; inappropriate shocks (two or more episodes); and sustained symptomatic AT lasting > 48 h. The outcome variable was a pre-specified score that corrected for clinical severity and follow-up duration. Three hundred and thirty-four patients were analysed (DC-ICD, n = 112; SC-ICD, n = 111; SC-simulated, n = 111). The mean left ventricular ejection fraction was 0.36 +/- 0.13, 69% were in functional class > or = II. CSAE occurred in 65 DC-ICD, 82 SC-ICD, and 84 SC-simulated patients. The outcome variable was 33% lower in the DC-ICD group (OR 0.31; 95% CI 0.14-0.67; P = 0.0028). Mortality was 4% in DC, 9% in SC, and 10% in SC-simulated.

Conclusion: In patients with a standard SC-ICD indication, DC-ICD was associated with less CSAE when compared with SC-ICD.

Trial registration: ClinicalTrials.gov NCT00157820.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Arrhythmias, Cardiac / mortality*
  • Arrhythmias, Cardiac / prevention & control*
  • Defibrillators, Implantable / statistics & numerical data*
  • Equipment Design
  • Equipment Failure Analysis
  • Europe
  • Female
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Risk Assessment / methods*
  • Risk Factors
  • Survival Analysis
  • Survival Rate

Associated data

  • ClinicalTrials.gov/NCT00157820