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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

Implantable defibrillator therapy

A M W Alings1

  • 1Department of Cardiology, Amphia Hospital, Molengracht 21, 4818 CK Breda, The Netherlands. Malings@Amphia.nl

The Netherlands Journal of Medicine
|August 16, 2003
PubMed

Insights

Implantable cardioverter-defibrillators (ICDs) are more effective than antiarrhythmic drugs (AADs) in preventing sudden cardiac death (SCD). ICDs show consistent benefits in both secondary and primary prevention for heart attack survivors with reduced ejection fraction.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Preventive Medicine

Background:

  • Sudden cardiac death (SCD) is a leading cause of mortality globally.
  • Antiarrhythmic drugs (AADs) have shown limited efficacy in preventing SCD, with beta-blockers being a notable exception.
  • This led to the development of trials comparing implantable cardioverter-defibrillators (ICDs) against drug therapy for SCD prevention.

Purpose of the Study:

  • To evaluate the efficacy of implantable cardioverter-defibrillators (ICDs) compared to antiarrhythmic drugs (AADs) in preventing sudden cardiac death (SCD).
  • To assess ICD benefit in both secondary and primary prevention settings, particularly in patients with a history of myocardial infarction and left ventricular dysfunction.

Main Methods:

  • Meta-analysis of three large randomized secondary prevention trials in patients resuscitated from ventricular tachycardia (VT) or ventricular fibrillation (VF) after myocardial infarction.
  • Analysis of three large randomized primary prevention trials in patients with prior myocardial infarction and left ventricular dysfunction.

Main Results:

  • Meta-analysis confirmed a consistent benefit of ICD therapy in secondary prevention post-myocardial infarction.
  • ICD therapy also demonstrated significant benefit in primary prevention for patients with prior myocardial infarction and left ventricular dysfunction.
  • The beneficial effect of ICDs was most pronounced in patients with the lowest left ventricular ejection fraction (26-30%).

Conclusions:

  • Implantable cardioverter-defibrillators (ICDs) are superior to antiarrhythmic drugs (AADs) for preventing sudden cardiac death (SCD) in specific patient populations.
  • ICD implantation is evidence-based for secondary prevention in patients with non-ischaemic dilated cardiomyopathy and low ejection fractions.
  • Further research may be warranted to optimize ICD use in primary prevention for diverse cardiomyopathies.

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