Results: 453 cases of sudden death from 1994 to 2003 (278 men (61.4%) and 175 women (38.6%), age range 15-81 years) were reviewed. Males predominated in both age groups (< or = 35 years, 35 years). More than half of the hearts (n = 269, 59.3%) were structurally normal. In the other 40.7%, cardiac abnormalities were noted, which included: (1) cardiomyopathies (23%) such as idiopathic fibrosis, left ventricular hypertrophy, hypertrophic cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic right ventricular dysplasia; (2) inflammatory disorders (8.6%) including lymphocytic myocarditis and cardiac sarcoidosis; (3) non-atheromatous abnormalities of coronary arteries (4.6%); (4) valve diseases; and (5) miscellaneous and rare causes.

Conclusion: The concept of the structurally normal heart in sudden death and the need for histological examination to detect underlying disease is highlighted. Relatives need to be referred for cardiological and genetic screening in cases of normal hearts found at necropsy

https://pubmed.ncbi.nlm.nih.gov/15923280/