Recent studies have proved close relations between cardiovascular and endocrinic systems. This relation has been observed in acromegaly, the disease connected with unrestrained secretion of growth hormone. The aim of the study was to assess Holter monitoring and echocardiography of acromegalic patients. The study group consisted of 28 acromegalic patients, including 15 patients with hypertension, was considered. As control groups we examined 20 patients with essential hypertension and 20 normotensive healthy subjects: All subjects underwent twenty-four hour Holter recordings, complete M-mode, two-dimentional and spectral Doppler echocardiography. Ventricular premature complexes occurred in 65% of acromegalic patients. Frequency and severity of ectopic beats were significantly increased compared to control groups. Left ventricular ejection fraction was considered to be normal, although significant decreased compared to healthy subjects. Left ventricular mass was above normal value in acromegalic patients--no significant difference was found between hypertensive and normotensive acromegalics. Doppler examination has shown the abnormalities of left and right ventricular filling in 89% of acromegalics. We have observed the correlations between left and right ventricular filling indices and the duration of the disease, and left ventricular mass. Left ventricular hypertrophy frequently occurs in acromegalic patients and this is not simply secondary to systemic hypertension. The prevalence of ventricular arrhythmias in acromegalic patients seems to be associated with left ventricular hypertrophy. Doppler examination suggests impaired left and right diastolic filling in patients with acromegaly.