Hypertrophic cardiomyopathy (HCM) is a primary myocardial disorder characterized by asymmetric left ventricular hypertrophy with myocyte and myofibrillar disarray. The wide diversity in cardiac morphology, pathophysiologic features and clinical manifestations is evident even within the same family. The aim of this study was to screen a group of patients for the incidence of familial hypertrophic cardiomyopathy (FHC). The study group comprised 65 subjects - members of 12 unrelated families. Overall, HCM was diagnosed in 24 out of 65 patients, mostly male - 20 cases. There were two cases of cardiomyopathy in women. FHC was confirmed in 7 out of the 12 screened families. Most often hypertrophy involved substantial portions of both the ventricular septum and anterolateral left ventricular free wall and qualified as type III, according to Marons' classification. During a 3 year follow-up period we observed no characteristics of progressive left ventricular hypertrophy nor left ventricular failure amongst 16 subjects treated with verapamil for an average period of 2 years and those without medication. The pattern of left venricular hypertrophy distribution was similar between first degree relatives, but the degree of hypertrophy varied significantly. The authors did not observe correlations between the pattern of distribution and degree of left ventricular hypertrophy, ecg disturbances and clinical manifestations.

Keywords: hypertrophic cardiomyopathy, Epidemiology, familial occurrence