Time to Shock the System: Moving Beyond the Current Paradigm for Primary Prevention Implantable Cardioverter-Defibrillator Use

• Type of Material: Article
• Authors: Faisal Merchant, Emory University; Wayne C. Levy, University of Washington; Daniel B. Kramer, Harvard Medical School
• Language: English
• Date: 2020-03-03
• Publisher: Wiley
• Publication Version: Final Published Version
• Copyright Statement: © 2020 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1161/JAHA.119.015139
• Title of Journal or Parent Work: Journal of the American Heart Association
• Volume: 9
• Issue: 5
• Start Page: e015139
• End Page: e015139
• Grant/Funding Information: None declared
• Keywords: Sudden cardiac death; Heart failure; defibrillation; Life Sciences & Biomedicine; Science & Technology; Prediction; Myocardial infarction; Cardiovascular System & Cardiology; Cardiac & Cardiovascular Systems; Mortality; Older patients; arrhythmia; Therapy; Clinical trials; sudden cardiac arrest; Risk stratification; Survival benefit
• Research Categories: Biology, Physiology; Health Sciences, Medicine and Surgery; Health Sciences, Rehabilitation and Therapy

Abstract

Primary prevention implantable cardioverter‐defibrillators (ICDs) play a crucial role in the treatment of patients at heightened risk of sudden cardiac death (SCD) caused by ventricular arrhythmias. The use of ICDs for primary prevention is supported by multiple, randomized clinical trials now codified into guidelines that drive clinical practice.1 However, there are well‐known shortcomings of the current paradigm, which determines primary prevention ICD candidacy based largely on left ventricular ejection fraction (LVEF) and heart failure class.2, 3 Most ICD recipients never receive appropriate device therapy, whereas others may receive shocks but die from progressive heart failure or noncardiac causes without deriving a meaningful survival benefit from the device.4 Despite well‐acknowledged limitations, there have been no significant new trials refining patient selection for primary prevention ICDs in nearly 15 years, with the guidelines themselves likely presenting a significant barrier to randomization. In this article, we review areas where current risk stratification algorithms perform poorly and highlight opportunities for improving decision making regarding ICD implantation. We also propose research and policy solutions for improving the yield of primary prevention ICD implantation.