A prospective randomized trial of single- or dual-chamber implantable cardioverter-defibrillators to minimize inappropriate shock risk in primary sudden cardiac death prevention

Paul A. Friedman, David Bradley, Celeste Koestler, Joshua Slusser, David Hodge, Kent Bailey, Fred Kusumoto, Thomas M. Munger, Arie Militanu, Michael Glikson

Research output: Contribution to journalReview article

22 Scopus citations


Aims: Dual-chamber implantable cardioverter-defibrillators (ICDs) may improve specificity and reduce the risk of inappropriate shocks, and enhance atrial arrhythmia (AT/AF) detection to permit stroke prevention compared with single-chamber ICDs, but at additional expense and risk. Methods and results: Patients (n = 100) receiving primary prevention ICDs at two USA and two Israeli centres were randomized to dual-chamber or single-chamber devices between December 2008 and December 2010 and were followed for 1 year. Programming in both groups included: delayed detection to avoid therapy for non-sustained episodes; high detection cut-off rates to avoid treating slower, better tolerated arrhythmias; minimized right ventricular pacing; and routine use of supraventricular-ventricular tahcycardia discriminators and antitachycardia pacing. The primary outcome was the proportion of patients with inappropriate shocks. One patient in each group (2%) received inappropriate shocks (P = 1.00). Death occurred in two patients in the single-chamber arm, and in none of the patients in the dual-chamber arm (P = 0.15). New AT/AF was detected in 12 patients (24%) in the dual-chamber group, vs. no patients in the single-chamber group (P < 0.001). Among US participants, the mean cost of dual- vs. single-chamber ICD implantation was $16 579 vs. $14 249, respectively (P < 0.001); there was no difference in the quality of life (EQ-5D index difference 0.013, P = 0.769; EQ VAS difference 3.3, P = 0.49). Conclusion: When optimal programming is utilized, inappropriate shocks are rare in primary prevention patients with both single- and dual-chamber ICDs. The routine use of dual-chamber ICDs increases the expense without reducing inappropriate shocks or improving the quality of life at 1 year.

Original languageEnglish (US)
Pages (from-to)1460-1468
Number of pages9
Issue number10
StatePublished - Jan 1 2014



  • Implantable defibrillator
  • Quality of life
  • Shock prevention
  • Single vs. dual chamber

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

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