Introduction Sudden cardiac death (SCD) from non-atherosclerotic causes is increasingly becoming recognised cause of death in the young. It is of major importance as it often concerns inheritable diseases. We report the cardiac pathology and demographics in non-atherosclerotic SCD referred for expert cardiac pathology examination to our tertiary centre in 18 years. To date this is the largest sudden cardiac death database for SCD.

Methods and results A total of 3225 cases were referred to CRY cardiovascular pathology unit for expert pathological analysis by MNS. Cases with coronary atherosclerotic disease (n = 190), congestive heart failure (n = 90) and other non-cardiac (n = 104) or post-op causes (n = 48) were included. Cases were classified into 2 age groups: 1–35 years and >35 years. The majority were young (57%, <35 years) and males dominated 2.8:1. Median age was 33 years, range <1–98 years. Less than 10% of deaths (n = 227) occurred in the paediatric age group (<16 years). In males the age group with the highest number of SCD was 26–30 years followed by 16–20 years. Females were older peaking 36–40 years. There is an upward trend in the referral number where the coefficient per year is 16 (11, 21). The overall increase is experienced after 2 years. SCD with a normal heart predominated (n = 1707, 53%) indicating possible ion-channelopathy or Sudden Adult Death Syndrome (SADS).

Cardiomyopathy accounted for almost a third of the deaths (n = 935, 29%) with LVH (n = 210, 10%) HCM (n = 161, 5%) and ARVC (n = 131, 4%) as the most significant contributors. Left ventricular hypertrophy (LVH) without evidence of disarray was the most common structural abnormality in our cohort and was associated with obesity in 18% of cases. Other important causes included inflammation, coronary artery pathology and complex CHD making up 12% of the cohort. A normal heart occurred mostly in the young (58%) and females were more commonly affected compared to males. The worldwide incidence of a normal heart in young sudden death is variable from 3.8%3 to 41%. Cardiomyopathy was most significantly associated with males and affected the older age groups.

Conclusion The CRY SCD database contains the largest world pathology series of non-atherosclerotic SCD in all ages. Particularly in the young the major cause of SCD is SADS, followed by cardiomyopathy. When the autopsy identifies SADS or primary cardiomyopathy, the families of victims with SADS or other inheritable cardiomyopathies should be referred for cardiological screening to expert centres. Because of the importance of expert opinion in diagnosis inherited cardiac disease, referral to specialist cardiac pathologists must be regarded as the ¡®gold standard¡¯.