Sudden cardiac death (SCD) is a major public health problem worldwide. Despite many advances in the care of sudden cardiac arrest (SCA), 90% of individuals with SCA do not survive. A major challenge in SCD prevention is that although the highest incidence of SCD is in known high-risk groups such as patients with previous sustained ventricular arrhythmias and those with heart failure, the absolute number of SCD events is highest among individuals who are not presently known to be at an increased risk of SCD. Another difficulty is that although current guidelines recommend implantable cardioverter-defibrillators for individuals at a high risk of SCD, a large number of these patients never receive a lifesaving therapy from their device. How to identify high-risk patients in low-risk groups and low-risk patients in high-risk groups remains a fundamental challenge. Recognizing the major impact of SCD and SCA on the lives of many individuals and the enormous burden of SCD and SCA, the Heart Rhythm Society convened a think tank meeting of stakeholders, "The Present and The Future of Risk Stratification for and Prevention of SCD." The objectives of the meeting were to (1) improve understanding of the current public health impact of SCD, (2) review the current state of prediction and prevention of SCD, (3) identify gaps in prediction and prevention of SCD, and (4) develop an action plan to address the identified gaps. This manuscript summarizes the proceedings of the meeting and proposes a plan for reducing the burden and impact of SCD.

Cardiac physiologic pacing, also known as cardiac resynchronization therapy, is indicated in patients with heart failure, reduced left ventricular ejection fraction (LVEF) of 50% or less, and either a high (or anticipated high) ventricular pacing burden or a wide QRS complex. Traditionally, physiologic pacing has been achieved with biventricular pacing with a right ventricular lead and a coronary sinus branch lead. Randomized trials involving more than 10,000 patients with heart failure have shown clinical, exercise, and quality-of-life benefits associated with biventricular pacing, as well as improved LVEF and reduced mitral regurgitation and ventricular volumes. These benefits are greatest in patients with left bundle-branch block and a QRS duration of 150 msec or longer. Recent studies support targeting the His bundle or left bundle branch as an alternative cardiac physiologic pacing strategy. Ongoing randomized trials are expected to more clearly define the comparative efficacy and safety of conduction system pacing as compared with biventricular pacing.

Out-of-hospital cardiac arrest remains a leading cause of mortality in the United States, with survival critically dependent on timely bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use. Despite strong evidence supporting early intervention, bystander-initiated CPR remains suboptimal, with persistent racial, demographic, socioeconomic, literacy-related, and geographic disparities. National legislative efforts have been hampered by inadequate funding. To improve out-of-hospital cardiac arrest survival and address these disparities, the Institute of Medicine has identified US high school students as a prime target for CPR education and AED use. Although most US states have legislated mandates for CPR and AED education, there is no consistent, standardized implementation process. 1-time or didactic-only training, limited hands-on practice, lack of longitudinal reinforcement, and inequitable AED access undermine effectiveness. This Heart Rhythm Society Scientific Statement evaluates the current landscape of CPR and AED education for US high school students, including the effectiveness of state legislative mandates, implementation strategies, and disparities in access and outcomes. We identify critical gaps and propose evidence-based solutions and an implementation framework for uniform, effective, and equitable initial and longitudinal CPR and AED training aiming to transform generations of US high school students into lifesavers.

Background The Seattle Proportional Risk Model (SPRM) estimates the proportion of sudden cardiac death (SCD) in heart failure (HF) patients, identifying those most likely to benefit from implantable cardioverter-defibrillator (ICD) therapy (those with ≥50% estimated proportion of SCD). The GISSI-HF trial tested fish oil and rosuvastatin in HF patients. We used the SPRM to evaluate its accuracy in this cohort in predicting potential ICD benefit in patients with EF ≤50% and an SPRM-predicted proportion of SCD either ≥50% or <50%. Methods The SPRM was estimated in patients with EF ≤50% and in a logistic regression model comparing SCD with non-SCD. Results We evaluated 6,750 patients with EF ≤50%. There were 1,892 all-cause deaths, including 610 SCDs. Fifty percent of EF ≤35% patients and 43% with EF 36% to 50% had an SPRM of ≥50%. The SPRM (OR: 1.92, P < 0.0001) accurately predicted the risk of SCD vs non-SCD with an estimated proportion of SCD of 44% vs the observed proportion of 41% at 1 year.By traditional criteria for ICD implantation (EF ≤35%, NYHA class II or III), 64.5% of GISSI-HF patients would be eligible, with an estimated ICD benefit of 0.81. By SPRM >50%, 47.8% may be eligible, including 30.2% with EF >35%. GISSI-HF participants with EF ≤35% with SPRM ≥50% had an estimated ICD HR of 0.64, comparable to patients with EF 36% to 50% with SPRM ≥50% (HR: 0.65). Conclusions The SPRM discriminated SCD vs non-SCD in GISSI-HF, both in patients with EF ≤35% and with EF 36% to 50%. The comparable estimated ICD benefit in patients with EF ≤35% and EF 36% to 50% supports the use of a proportional risk model for shared decision making with patients being considered for primary prevention ICD therapy.