Revisiting ICD Therapy for Primary Prevention in Patients With Heart Failure and Reduced Ejection Fraction

Implantable cardioverter-defibrillators (ICDs) are recommended to reduce the risk of sudden cardiac death (SCD) in patients with heart failure with reduced ejection fraction (HFrEF). The landmark studies leading to the current guideline recommendations preceded the 4 pillars of guideline-directed medical therapies (GDMTs). Therefore, some have questioned the role of ICDs for primary prevention in current clinical practice. In this paper, the authors provide an overview of the current ICD recommendations, including the instrumental clinical trials, the risk of SCD as observed in clinical trials vs real-world scenarios, disparities in ICD use among different patient populations, the impact of contemporary GDMT on outcomes, and ongoing and future trials and methodologies to help identify patients who are at an increased risk of SCD and who may benefit from an ICD. The authors also propose a pragmatic guidance for clinicians when they engage in the shared decision-making discussions for primary ICD implantation. (JACC Heart Fail. 2025;13:1-13) (c) 2025 by the American College of Cardiology Foundation.