Congestive heart failure affects over five million people in the United States with over 500,000 new cases reported annually. About half of patients die from heart failure related causes within the first 5 years of diagnosis. Conventional medical therapy including beta blockers, renin-angiotensin antagonists, aldosterone antagonists, and more recently angiotensin receptor neprilysin inhibitors, glucagon-like peptide 1 receptor agonists, and sodium-glucose cotransporter-2 inhibitors have further improved morbidity and mortality in this population. However, sudden cardiac death (SCD) remains a leading cause of death in this group of patients. Implantable cardioverter-defibrillators (ICDs) were initially used to prevent future arrhythmic deaths in patients who survived SCD. Utilization of ICDs was expanded when landmark clinical trials demonstrated that ICDs reduce mortality, particularly due to arrhythmic events, in various heart failure populations. Although advances in medical therapy for systolic heart failure have reduced cardiovascular mortality, ICD implantation remains the standard of care in his cohort, regardless of the etiology of heart failure.