Abstract 18129: Age-related Distribution of Structural Substrates of Sudden Cardiac Death in the Young
Objective. To establish the age-distribution of various causes of sudden cardiac death (SCD) as assessed at autopsy in a consecutive series of cases occurring in young people (aged 1-40 yrs).
Design and Results. In the time interval 1980-2011, 594 SCDs in the young (185 female, mean age 25±9 yrs) have been prospectively studied according to a uniform pathology protocol in our referral pathology Centre. The mechanism of SCD was mechanical in 37 (6%), while in the remaining 557 (94%) was arrhythmic. Major causes included atherosclerotic coronary artery disease (ath-CAD 108, 18%), myocarditis (72, 12%), arrhythmogenic right ventricular cardiomyopathy (ARVC 58, 10%), hypertrophic cardiomyopathy (HCM 55, 9%), dilated cardiomyopathy (22, 4%), non ath-CAD (41, 7%) and mitral valve prolapse (MVP 45, 7.5%). In 101 cases (17%) the heart was structurally normal at autopsy (“unexplained SCD”). To analyze the age-related distribution of various causes of SCD, we subdivided the study population in four age-groups, i.e. group I ≤10 yrs old (7%), group II 11-20 (21%), group III 21-30 (37%), and group IV 31-40 (35%). In group I, myocarditis was the leading cause (30%), followed by HCM (17%), DCM (12%) and non ath-CAD (12.5). In group II and III the leading causes were myocarditis (14% and 12%), ARVC (both 13%), HCM (both 11%), followed by non ath-CAD (10% and 5%) and MVP (5% and 6%). Noteworthy, ath-CAD accounted for 16% in group III and 34% in group IV, while it was present in only 2.5% in group II and was never detected in group I. SCD victims with ath-CAD were older than those with other substrates (31.5 vs. 25 yrs, p<0.0001). Unexplained SCD ranged from 15% (groups I, III and IV) to 25% (group II).
Conclusions. An age-related distribution of structural substrates of SCD in the young is found at autopsy. In people older than 30 yrs, ath-CAD is by far the most common cause accounting for more than one-third of all SCDs. Children and adolescents more often die due to non ath-CAD and cardiomyopathies, either inflammatory and inherited. Ath-CAD, ARVC and MVP are never observed before the age of 10. The high prevalence of structurally normal heart underlie the crucial role of molecular pathology while investigating SCD in the young.
- © 2012 by American Heart Association, Inc.