In 50 patients with different forms of hypertrophic cardiomyopathy the effect of many months (mean 23.3 +/- 15.7) therapy with verapamil was estimated. Interventricular septum thickness, isovolumetric relaxation period (IRP), "a" wave amplitude were evaluated as well as changes of parameters indirectly testifying to intraventricular obstruction such as: abnormal systolic anterior mitral leaflet motion (SAM) and midsystolic aortic valve closure (AVC). Pre- and post therapy physical efficacy was estimated basing on effort duration. Results were compared with those observed in a group of 20 patients with hypertrophic cardiomyopathy not treated with calcium channel antagonists. Verapamil therapy resulted in inhibition of a disease progression and in diminution of interventricular septum thickness respectively in 74% and 48% of patients. Differences are significant in comparison with a control group. Characteristics of diastole was improved almost in a half of verapamil patients. In the majority of cases, active diastolic period improvement was referred to patients with nonobstructive cardiomyopathy forms and corresponded with their physical fitness improvement. Verapamil resulted in diminution or regression of SAM and AVC in patients with obstructive forms and most likely caused physical efficacy improvement in some of them. The study also confirmed that the group of patients with hypertrophic cardiomyopathy is not homogenous one with regard to morphology of hypertrophy, hemodynamics, disease progression and response to therapy. Observed differences do not always depend on a cardiomyopathy form which suggests that the applied nowadays classification is not sufficient.