In our retrospective study, we evaluated whether ACE inhibitors can influence left ventricular (LV) morphofunctional characteristics in essential hypertension independently of the antihypertensive effect. We studied 21 hypertensive patients (group 1) before and after at least 18 months of treatment with ACE inhibitors that did not induce any blood pressure (BP) reduction; as a control group, we evaluated 19 hypertensive patients (group 2) not treated with antihypertensive drugs during the same period. At baseline, the 2 groups, neither one previously treated with antihypertensive drugs, were not significantly different with regard to sex, age, body mass index, 24-hour BP, and heart rate; LV mass index was similar between the groups, whereas LV diastolic indices were significantly lower in group 1. At the second evaluation, body mass index, 24-hour BP, and heart rate were unchanged in both groups; LV mass index was significantly decreased in group 1 and increased in group 2. LV diastolic parameters were significantly improved in group 1, whereas in group 2, diastolic function was significantly deteriorated. In conclusion, our clinical study shows that ACE inhibitors can induce LV hypertrophy regression and improvement of diastolic function also in the absence of any antihypertensive effect.