Head-to-head comparison of arrhythmia discrimination performance of subcutaneous and transvenous ICD arrhythmia detection algorithms: the START study

J Cardiovasc Electrophysiol. 2012 Apr;23(4):359-66. doi: 10.1111/j.1540-8167.2011.02199.x. Epub 2011 Oct 28.


Background: The development of a totally subcutaneous implantable defibrillator (S-ICD) system requires a new approach for arrhythmia detection. To evaluate arrhythmia discrimination of one such system, the Subcutaneous versus Transvenous Arrhythmia Recognition Testing (START) study was designed as a prospective, multicenter trial comparing simulated sensing performances of the S-ICD system with single- (SC-TV) and dual-chamber transvenous (DC-TV) implantable cardioverter-defibrillator (ICD) systems.

Methods: At ICD implantation, induced ventricular and atrial arrhythmias were recorded simultaneously in transvenous (right ventricular [RV] → superior vena cava [SVC]+ Coil) and cutaneous electrode configurations. Recorded signals of ventricular (n = 46) and atrial arrhythmias (n = 50) with ventricular rates >170 bpm from 64 patients were used to compare detection performance of the S-ICD system with TV-ICD systems from 3 manufacturers. Appropriate detection of ventricular tachyarrhythmias was assessed with devices programmed in single-zone (rate ≥ 170 bpm) and dual-zone configurations (ventricular fibrillation ≥ 240 bpm; ventricular tachycardia ≥ 170 bpm). S-ICD specificity performance for supraventricular arrhythmias was compared to single- and dual-chamber devices in a dual-zone configuration.

Results: Appropriate detection of ventricular tachyarrhythmias for subcutaneous and TV devices in single- and dual-zone configurations was 100% and >99%, respectively. Specificity for supraventricular arrhythmias was significantly better for the S-ICD system compared to 2 of 3 TV systems, as well as the composite of TV devices (98.0%[S-ICD] vs 76.7%[SC-TV range: 64.0-92.0%] vs 68.0%[DC-TV range: 32.7-89.8%; P < 0.001]).

Conclusion: Appropriate ventricular arrhythmia detection is excellent for all ICD systems evaluated; however, specificity of supraventricular arrhythmia discrimination by the S-ICD system is better than discrimination by 2 of 3 TV systems.

Publication types

  • Comparative Study
  • Multicenter Study

MeSH terms

  • Aged
  • Algorithms*
  • Arrhythmias, Cardiac / diagnosis*
  • Arrhythmias, Cardiac / therapy*
  • Computer Simulation
  • Defibrillators, Implantable*
  • Electric Countershock / instrumentation*
  • Electrocardiography / instrumentation*
  • Electrophysiologic Techniques, Cardiac
  • Equipment Design
  • Female
  • Humans
  • Male
  • Materials Testing
  • Middle Aged
  • Predictive Value of Tests
  • Prospective Studies
  • Sensitivity and Specificity
  • Signal Processing, Computer-Assisted*