The clinicopathologicspectrum of hypertrophiccardiomyopathy. The experience of the italian heart transplant program

Hypertrophic cardiomyopathy (HCM) is an idiopathic cardiac disease which is predominantly genetic in origin and transmitted as an autosomally dominant trait [1, 2]. The mutated genes code for altered contractile myofibrillar proteins, leading to deformed myocytes and histological evidence of extensive myocell disorganization, namely the disarray typical of hypertrophie cardiomyopathy (HCM). In the natural history of HCM endstage heart failure is relatively infrequent and associated with a pattern of left ventricular systolic impairment with cavity dilatation, which occurrs in about 10% of patients [3, 4], with a yearly incidence of 1.5% [5]. End-stage disease may coexist with premature sudden death in family members carrying the same genetic abnormality [6]. This pattern is characterized by a particularly poor prognosis, so that heart transplantation has been advocated in this subgroup of patients.