To evaluate the effect of age on left ventricular hypertrophy-related arrhythmias in patients with essential arterial hypertension, 68 hypertensives (47 men and 21 women, mean age 59.4 +/- 9.5 years) without other cardiovascular disorders were studied. All patients underwent M-mode and two-dimensional echocardiogram and 24 h ambulatory electrocardiographic monitoring to measure left ventricular internal dimension, septum and posterior wall thickness, left ventricular mass index, premature ventricular beats and modified Lown grade. Premature ventricular beats (PVB) and modified Lown grade were significantly related to left ventricular mass index, but not to left ventricular internal dimension, fractional shortening, systolic and diastolic blood pressure. There was no relation between age and number of PVB, or severity of arrhythmias. In conclusion, in hypertensive patients only left ventricular hypertrophy, and not age, plays a significant role in the pathophysiology of the increased incidence of ventricular arrhythmias by a different mechanism than age-related increased ventricular arrhythmias.