The autopsy study of 553 cases of sudden cardiac death in Chinese adults.

Despite a recent epidemiological study reporting a lower incidence of sudden cardiac death (SCD) in China as compared with that in Western countries, the exact causes of SCD are still unknown. Using a uniform review protocol and diagnostic criteria, a retrospective autopsy study identified 553 cases of SCD in 14,487 consecutive autopsies from eight regions in China representing different geographic and population features. Their ages ranged from 18 to 80 years (median 43.0 years) with a ratio of 4.3/1.0 for male/female. Out-of-hospital deaths and unwitnessed cases accounted for 74.3 and 22.6 %, respectively. The main causes of death were coronary atherosclerotic disease (CAD 50.3 %), myocarditis (14.8 %), and hypertrophic cardiomyopathy (4.5 %), with unexplained sudden death accounting for 12.1 % of the cases. CAD had a proportion of 10.4 % in victims <35 years, lower as compared with 59.0 and 83.0 % in victims aged 35-54 and in victims ≥55 years. On the other hand, myocarditis and unexplained sudden death were major causes and accounted for 34.7 and 22.5 % in victims <35 years. In order to differentiate the degree of the cause-effect relationship between autopsy findings and sudden death, a grading method was used in this series and characterized 24.3 % of findings as certain, 52.9 % as highly probable, and 22.8 % as uncertain. Our data indicated that there most likely are less CAD but more myocarditis and unexplained sudden death in Chinese youth with SCD than in populations from Western countries. Molecular genetic testing should be conducted in those cases with uncertain findings and unexplained sudden death in routine autopsy.