Sudden cardiac death and implantable cardioverter defibrillators: two modern epidemics?

Critical analysis of the existing evidence indicates that: In patients with documented sustained ventricular arrhythmias and/or cardiac arrest, implantable cardioverter defibrillators (ICDs) confer a survival benefit. In several clinical settings this is rather transient, and might be lost when modern medical therapy including -blockers is implemented. In patients without sustained ventricular arrhythmias or cardiac arrest, ICDs confer a significant survival benefit only in high-risk patients with ischaemic cardiomyopathy and left ventricular ejection fraction of 35 due to a remote myocardial infarction. Left ventricular ejection fraction alone is rather unlikely to be sufficient for effective sudden cardiac death risk prediction, due to low sensitivity and specificity. The benefits of ICDs in the elderly as well as in women are not established. With current prices, ICDs are probably cost-effective only when used in high-risk patients without associated comorbidities that limit the life expectancy to 10 years. Recommendations by current guidelines may result in unnecessary overuse of ICD.