At what ejection fraction is an implanted defibrillator indicated for CHF patients?

An implanted defibrillator, specifically a cardioverter-defibrillator (ICD), is indicated for patients with chronic heart failure (CHF) if their ejection fraction is less than 35%. This is based on clinical evidence suggesting that patients with significantly reduced ejection fraction are at higher risk for life-threatening ventricular arrhythmias, which can lead to sudden cardiac death. The device is used as a preventive measure to reduce mortality in these high-risk patients by delivering electric shocks when dangerous arrhythmias are detected.

A reduction in ejection fraction indicates impaired cardiac function, and an ejection fraction below 35% serves as a threshold for considering the use of an ICD, especially in patients with symptomatic heart failure or those who have experienced specific cardiac events. This guideline helps practitioners identify candidates who would benefit the most from this life-saving intervention. Thus, the indication for an implanted defibrillator is firmly established around this pivotal ejection fraction level, reinforcing its critical role in managing patients with severe heart failure.