Contemporary hypertrophic cardiomyopathy (HCM)-related sudden cardiac death (SCD) rates have significantly decreased within the last 60 years. But high rates were found in young patients with HCM, and there geographical disparities in receiving SCD prevention treatment, according to a study published Sep. 28 in JACC: Clinical Electrophysiology.

Omar M. Abdelfattah, MD, et al., systematically searched electronic databases up to November 2021 for studies reporting on SCD rates in HCM patients. A total of 98 studies qualified, with 70,10 patients, comprising 431,407 patient-years and 2,183 SCD events for analysis. Researchers used a random-effects model to pool study estimates and calculate the overall incidence rates for each time-era, geographic region and age group. Two time-eras were analyzed: before and after 2000, following clinical implementation of ICD in HCM. Following 2000, 5-year intervals were used to demonstrate the temporal change in SCD rates.

Results show that contemporary HCM-related SCD rates are low (0.30%/y), representing a significant decrease compared to treatment eras prior to the application of primary prevention ICD for HCM. However, young patients <18 years of age demonstrated a greater than two-fold-risk for sudden deaths vs. adults (IR: 1.09%; 95% CI: 0.69%-1.73% vs. IR: 0.43%; 95% CI:0.37%-0.50%). Reported SCD rates for HCM were lowest in North America (IR: 0.28%; 95% CI: 0.18%-0.43%,) and highest in Asia (IR: 0.67%; 95% CI: 0.54%-0.84%).

The authors note, “maturation of SCD risk stratification strategies and the application of primary prevention ICD to HCM are likely responsible for the notable decline in SCD events over the last several decades,” but that geographic disparities in SCD were evident and show the importance of increasing access to SCD prevention treatment for all HCM patients.

Clinical Topics: Arrhythmias and Clinical EP, Heart Failure and Cardiomyopathies, Prevention, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias

Keywords: Asia, Electronics, North America, Electrophysiology, Risk Assessment, Primary Prevention, Cardiomyopathy, Hypertrophic, Death, Sudden, Cardiac, Incidence, Adult

< Back to Listings