The aim of this study was to evaluate left ventricular function in 26 patients with essential arterial hypertension, compared with 33 normal subjects, using gated radionuclide ventriculography. The hypertensive patients had reduced values of ventricular ejection fraction (EF), peak ejection and peak filling (PRF) rates. A group of 10 hypertensive patients with normal EF, showed significantly reduced values of PFR, as compared to normal subjects. The older hypertensive patients had significantly reduced PRF values, compared to younger patients. PFR is a more sensitive index in evaluating the impairment of ventricular function in patients with hypertension, though it lacks real discriminating diagnostic value. In hypertrophic heart disease the association between arterial hypertension and old age contributed to accentuate the abnormality in ventricular diastolic filling.