Hamartomatous malformation of the left ventricle associated with sudden death

We describe unusual left ventricular cardiac lesions in a 17 year old boy who died suddenly during exertion. These consisted of two grossly evident regions of deficient myocardium, containing cavernous spaces which represented exaggerated intertrabecular regions of the left ventricular cavity. Dense fibro-elastotic tissue was deposited around these spaces along with a variable admixture of mature adipose tissue, fibrous tissue and blood vessels. The etiology of these presumably congenital developmental abnormalities is obscure. The lesions most probably represent a hamartomatous malformation, which is a poorly documented pathological entity.