This study was undertaken to determine the chronic effects of a long-acting
calcium-channel blocker (
nitrendipine) on resting left ventricular filling abnormalities in ten patients with
essential hypertension.
Radionuclide left ventricular curves of these hypertensive patients were compared with the curves of twelve normal volunteers and of eight asymptomatic older patients. The curves were analyzed for ejection fraction, peak filling rate (normalized for end-diastolic counts and for
stroke counts), time to peak filling rate and filling fraction in the first-third of diastole normalized for cycle length. Heart rate and ejection fraction were similar in both control groups and hypertensive patients before and after
nitrendipine. Before
nitrendipine, diastolic filling parameters were significantly different in the hypertensive patients as compared with the volunteers and with the asymptomatic aged patients: peak filling rate was lower, time to peak filling rate was longer and the first-third filling fraction was smaller. After six weeks of
nitrendipine therapy, systolic and diastolic blood pressure decreased significantly. After
nitrendipine, the time to peak filling rate decreased and the first-third filling fraction and the peak filling rate (normalized for
stroke counts) increased significantly. The acute
oral administration of 100 mg
atenolol induced a further decrease in systolic blood pressure and a significant decrease in heart rate. The effect of combining
nitrendipine and
atenolol on diastolic indexes was a preserved effect on time to peak filling rate and on the first-third filling fraction. These results suggest that short-term
therapy with
nitrendipine improves early diastolic dysfunction in hypertensives: the addition of a beta-blocking agent further improved the early diastolic indexes.