Essential hypertension is characterized by a left ventricular dysfunction. However, the majority of the studies performed so far investigated patients under drug treatment and/or with concomitant diseases, such as obesity, diabetes, metabolic syndrome or coronary heart disease, which per se may affect diastolic function independently on the blood pressure elevation. The present study aimed at investigating left ventricular diastolic function in untreated, uncomplicated and newly diagnosed hypertensive patients by employing both routine echo-Doppler and pulse tissue-Doppler technique. Data were collected in 86 middle-aged essential hypertensive patients and in 18 sex-matched normotensive controls. At the echo-Doppler approach, about half of the hypertensive patients displayed a diastolic dysfunction (n = 44, E/A: 0.79 +/- 0.02). They showed body mass index values slightly greater than hypertensive patients without diastolic dysfunction but superimposable blood pressure values and metabolic variables. When assessed via the pulse tissue-Doppler approach, patients with a reduced E/A displayed an Em/Am ratio significantly lower than patients without diastolic dysfunction and control subjects. This was the case when the data were related to the lateral and septal mitral annulus or averaged together. Furthermore, whereas myocardial systolic peak velocity (Sm) was lower in hypertensive patients than in control subjects, no significant between-groups difference in E/Em ratio was observed. Differently from the data obtained via the echo-Doppler approach, the tissue-Doppler method in patients without diastolic dysfunction showed a significant higher deceleration and isovolumetric relaxation times, with a lower Em velocity compared with the normotensive subjects. At the stepwise multiple regression analysis E/A ratio and E'/A' values were related with left ventricular mass index and body mass index after correction for age. These data provide evidence that diastolic dysfunction is of frequent detection in the earlier uncomplicated phases of the disease and that tissue Doppler detects an initial impairment of left ventricular relaxation in the patients in which at echo Doppler is still normal.