Implantable cardioverter-defibrillators: indications and unresolved issues

Area of Science:

• Cardiology
• Medical Devices

Background:

• Implantable cardioverter-defibrillators (ICDs) have been clinically available since 1980.
• Numerous randomized controlled trials (RCTs) have established the efficacy of ICD therapy across diverse patient groups.

Purpose of the Study:

• To review the established benefits of ICD therapy.
• To identify areas requiring further investigation regarding ICD use.

Main Methods:

• Systematic review of evidence from large randomized controlled trials.
• Analysis of data supporting ICD use in primary and secondary prevention of sudden cardiac death.
• Evaluation of ICDs in conjunction with cardiac resynchronization therapy (CRT).

Main Results:

• ICD therapy is beneficial for secondary prevention in patients with a history of arrhythmic events.
• ICDs are effective in primary prevention for patients with coronary artery disease and nonischemic cardiomyopathy.
• Combined ICD and CRT therapy improves survival and quality of life in severe heart failure patients.

Conclusions:

• ICD therapy is a proven intervention for preventing sudden cardiac death in selected populations.
• Further research is warranted to optimize ICD use in elderly, female, and hemodialysis-dependent patients.
• Optimal timing for ICD implantation post-myocardial infarction, revascularization, or heart failure diagnosis requires further study.