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A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
16:40

A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation

Published on: February 28, 2012

Indications for internal cardioverter defibrillator implantation predict time to first shock and the modulating

Haitham Hreybe1, Maninder Bedi, Rana Ezzeddine

  • 1University of Pittsburgh, Pittsburgh, PA 15213, USA.

American Heart Journal
|November 18, 2005
PubMed

Insights

Implantable cardioverter-defibrillator (ICD) shock risk varies by indication. Secondary prevention patients face higher shocks, but beta-blockers improve shock-free survival.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Devices

Background:

  • Implantable cardioverter-defibrillators (ICDs) are used for various cardiac conditions.
  • The influence of specific ICD indications on shock timing is unclear.
  • The role of beta-blockers in modifying shock-free survival needs further clarification.

Purpose of the Study:

  • To investigate how different indications for ICD implantation affect the time to the first shock.
  • To evaluate the impact of beta-blocker therapy on shock-free survival in ICD patients.

Main Methods:

  • Retrospective analysis of 230 patients undergoing ICD implantation.
  • Patients categorized into four groups based on ICD indication (secondary prevention, LVEF criteria).
  • Kaplan-Meier method used to analyze time to first shock, with subgroup analysis for beta-blocker use.

Main Results:

  • Overall 1-year shock-free survival varied significantly by indication (57% to 91%).
  • Patients with secondary prevention indications had lower shock-free survival (57% total, 75% appropriate shocks).
  • Beta-blocker use in secondary prevention patients increased 1-year shock-free survival (48% to 61% total shocks).

Conclusions:

  • ICD implantation indication, not electrophysiology study results, predicts time to first shock.
  • Patients receiving ICDs for secondary prevention are at the highest risk of shocks.
  • Beta-blockers demonstrably increase time to first shock in patients with secondary prevention indications.
Abstract

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