Causes of sudden cardiac death in young athletes and non-athletes: systematic review and meta-analysis ' ?? Sudden cardiac death in the young

Introduction: The etiology of sudden cardiac death (SCD) in young people continues to attract much attention. This meta-analysis aimed to identify the most frequent causes of SCD in individuals aged <35 years, the differences between athletes and non-athletes and geographic areas.Methods: Studies published between 01/01/1990 and 01/31/2020 and evaluating post-mortem the aeti-ology of SCD in young individuals ( <35 years) were included. Individuals were divided into athletes and non-athletes. Studies that did not report separate data between athletes and non-athletes were excluded.Results: Thirty-four studies met the inclusion criteria, and a total population of 5,060 victims of SCD were analyzed (2,890 athletes, 2,170 non-athletes). Comparing the causes of SCD between athletes and non-athletes, non-ischemic left ventricular scar (NILVS) (5.1% vs. 1.1%, p = 0.01) was more frequent in the former, while coronary artery disease (CAD) (19.6% vs. 9.1%, p = 0.009), arrhythmogenic cardiomyopathy (ACM) (11.5% vs. 4.7%, p = 0.03) and channelopathies (8.4% vs. 1.9%, p = 0.02) were more frequent in the latter. In studies published in the last decade, hypertrophic cardiomyopathy (HCM) (p = 0.002), dilated cardiomyopathy (p = 0.047), and anomalous origin of coronary arteries (AOCA) (p = 0.009) were more fre-quently the causes of SCD in athletes while aortic dissection (0.022) was the cause in non-athletes. HCM (p = 0.01) and AOCA (p = 0.004) were more frequently the causes of SCD in the US while ACM (p = 0.001), structurally normal heart (p = 0.02), and channelopathies (p = 0.02) were more frequent in Europe. Conclusions: Among the causes of SCD, NILVS was the more frequent cause in athletes, while CAD, ACM and channelopathies were more frequent causes in non-athletes. The causes of SCD differ between the US and Europe.(c) 2021 Elsevier Inc. All rights reserved.