Assessment of the anti-hypertensive effect of diltiazem in delayed-action capsules by ambulatory monitoring of arterial pressure]

The aim of this parallel controlled-placebo study was to assess the antihypertensive effect of diltiazem in a slow release formulation in monotherapy by the ambulatory blood pressure monitoring (ABPM). Twenty patients with moderate essential hypertension entered the trial. Whole day ambulatory blood pressure (BP) monitoring, with a COLIN ABPM 630, was done after a wash-out period, after placebo administration and 60 days of therapy with diltiazem in a 120 or 180 mg once or twice daily administration. We verified by ABPM that placebo administration did not have an antihypertensive effect (146 +/- 10 mmHg/87 +/- 7 mmHg at base line to 145 +/- 8 mmHg/84 +/- 6 mmHg with placebo p = ns). Eithy four percent of the patients showed a significant systolic and diastolic BP decrease after 60 days of therapy (from 146 +/- 10 mmHg/87 +/- 7 mmHg at base line to 132 +/- 7/77 +/- 6 mmHg - p less than 0.025). In 56% of the patients this was achieved with 180 mg/day and this effect was sustained throughout the 24 hours. We did not find a significant decrease on heart rate. The ABPM is a valuable technique to assess the effect of antihypertensive drugs and demonstrated that diltiazem in a slow release formulation was effective in decreasing systolic and diastolic BP, throughout the day even in patients with low doses, once daily.