Death without prior appropriate implantable cardioverter-defibrillator therapy: a competing risk study

Area of Science:

• Cardiology
• Medical Devices
• Clinical Research

Background:

• Implantable cardioverter-defibrillators (ICDs) are proven to improve survival in specific heart failure populations.
• However, in routine care, competing risks like death before ICD therapy may limit benefits.

Purpose of the Study:

• To evaluate the risk of death without appropriate ICD therapy in a contemporary patient cohort.
• To identify predictors of ICD therapy versus death without therapy.

Main Methods:

• A single-center prospective registry analysis of 442 patients with ischemic or dilated cardiomyopathy receiving ICDs (1994-2006).
• Competing risk regression was used to analyze time to first appropriate ICD therapy or death without prior therapy.

Main Results:

• Over a median of 3.6 years, 52% received appropriate ICD therapy, while 11% died without it.
• 23% died without therapy for ventricular fibrillation, compared to 13% receiving such therapy.
• Diuretic use for heart failure predicted a 4-fold increased risk of death before ICD therapy.

Conclusions:

• A substantial risk of death without prior appropriate ICD therapy exists in contemporary patients.
• This risk is particularly elevated in patients with advanced heart failure, underscoring the need for careful patient selection.