Arrhythmogenic cardiomyopathy: right, left, both

Abstract

The index case is a 64-year-old man with a past medical history of emphysema, who was found dead at home. The cause of death at autopsy was ischaemic heart disease. An incidental finding of myocyte necrosis, fibrosis and fatty infiltration was found in the left ventricle epicardium, suggestive of arrhythmogenic cardiomyopathy (ACM). Family members were referred for further investigation. ACM is a rare genetic condition associated with sudden death. Fibrofatty tissue replaces myocardium, starting from the epicardial surface. ACM is often described in the right ventricle although left ventricular involvement is possible. Cases of ACM over 22 years were reviewed at a large mortuary. In 19 cases, ACM was diagnosed with certainty, while ‘suspected ACM’ was diagnosed in 23 cases. The latter cohort had more comorbidities and decedents were older. In the combined group of 42 individuals, the distribution of pathology was as follows: 57% biventricular, 29% right ventricle and 14% left ventricle. ACM can be a subtle incidental finding, but with significant implications for family. We share the macro and microscopic features and compare differences amongst diagnosed versus suspected cases. Issues of search satisfaction and diagnostic uncertainty in older and often co-morbid patients are discussed.