What ejection fraction (EF) qualifies for LifeVest or Automatic Implantable Cardioverter-Defibrillator (AICD)?

From the Guidelines

An ejection fraction (EF) of 35% or less typically qualifies a patient for consideration of a LifeVest wearable defibrillator or an implantable cardioverter-defibrillator (ICD). Patients with an EF of 35% or less are at higher risk for life-threatening arrhythmias and sudden cardiac death, as indicated by the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1. The LifeVest is often used as a temporary measure for patients who are at risk but not yet ready for a permanent ICD. An ICD is usually considered for long-term protection.

Additional considerations for qualifying for a LifeVest or ICD include:

• The patient should have a life expectancy of more than one year
• The low EF should persist despite at least 3 months of optimal medical therapy
• The cause of the low EF (e.g., ischemic vs. non-ischemic cardiomyopathy) may influence the decision Other factors, such as the patient's overall health, specific cardiac condition, and personal preferences, are also taken into account, as noted in the European Society of Cardiology's task force on sudden cardiac death 1. A thorough evaluation by a cardiologist is necessary to determine the most appropriate treatment plan. The most recent and highest quality study, the 2022 AHA/ACC/HFSA guideline, provides the strongest evidence for the recommendation of an EF of 35% or less for consideration of a LifeVest or ICD 1.

From the Research

Ejection Fraction Qualification for LifeVest or AICD

• The qualification for LifeVest or Automatic Implantable Cardioverter-Defibrillator (AICD) is typically based on a left ventricular ejection fraction (LVEF) of ≤35% 2, 3, 4.
• Current guidelines recommend an implantable cardioverter-defibrillator (ICD) for prevention of sudden death in patients with heart failure and reduced ejection fraction (HFrEF) specifically those with a LVEF ≤35% after at least 3 months of optimized HF treatment 3.
• However, the evidence for a benefit of prophylactic ICD implantation in patients with HFrEF of non-ischaemic aetiology is less strong, and other risk parameters such as late gadolinium enhancement on cardiac magnetic resonance imaging and genetic testing for high-risk genetic variants should be considered 5.
• Patients with improved left ventricular ejection fraction (EF) to >35% after implantation (HFimpEF) have a reduced risk of appropriate ICD therapies and sudden cardiac death, but the risk is not eliminated 6.

Considerations for ICD Implantation

• The decision to implant an ICD should take into account additional risk parameters for both arrhythmic and non-arrhythmic death, such as age, comorbidities, and sex 5.
• The presence of advanced New York Heart Association stage predicts both total mortality and cardiac death 2.
• The use of disease-modifying therapies such as beta-blockers, mineralocorticoid receptor antagonists, and angiotensin receptor-neprilysin inhibitors may reduce the risk of sudden cardiac death in patients with HFrEF 3.
• The risk of appropriate ICD therapies and sudden cardiac death is lower in patients with HFimpEF, especially those with super-response (EF ≥50%) 6.