Amiodarone or an implantable cardioverter-defibrillator for congestive heart failure

Gust H Bardy1, Kerry L Lee, Daniel B Mark

  • 1Seattle Institute for Cardiac Research, Seattle, WA 98103, USA. gbardy@sicr.org

Insights

Sudden cardiac death in heart failure patients is a concern. Implantable cardioverter-defibrillator (ICD) therapy significantly reduced mortality by 23% compared to placebo, while amiodarone showed no survival benefit.

Area of Science:

  • Cardiology
  • Clinical Trials
  • Heart Failure Management

Background:

  • Sudden cardiac death is a primary cause of mortality in congestive heart failure (CHF) patients.
  • Amiodarone and implantable cardioverter-defibrillators (ICDs) are potential interventions to improve prognosis.

Purpose of the Study:

  • To compare the efficacy of amiodarone and ICD therapy versus conventional therapy in reducing mortality in CHF patients.
  • To evaluate the impact of these treatments on overall survival rates.

Main Methods:

  • A randomized trial involving 2521 patients with NYHA class II/III CHF and LVEF ≤ 35%.
  • Patients were assigned to conventional therapy with placebo, amiodarone, or a single-lead, shock-only ICD.
  • The primary endpoint was all-cause mortality, with a median follow-up of 45.5 months.

Main Results:

  • ICD therapy was associated with a 23% reduction in the risk of death compared to placebo (HR, 0.77; P=0.007).
  • Amiodarone showed no significant difference in mortality risk compared to placebo (HR, 1.06; P=0.53).
  • ICD therapy resulted in an absolute mortality reduction of 7.2 percentage points after five years.

Conclusions:

  • In patients with moderate to severe CHF and reduced ejection fraction, amiodarone does not improve survival.
  • Single-lead, shock-only ICD therapy is effective in reducing overall mortality in this patient population.
Abstract

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