Effect of moxonidine and cilazapril on microcirculation as assessed by finger nailfold capillaroscopy in mild-to-moderate hypertension.

Disorders in peripheral microcirculation are observed in arterial hypertension and may be improved by antihypertensive treatment. In this pilot study the authors measured capillary blood cell velocity in the finger nailfold in 14 patients (mean age 50 +/- 14 years, range 30-71 years; 9 men, 5 women) with mild-to-moderate essential hypertension. After a 3-week placebo period, patients received double-blind randomized treatment with either 0.2- to 0.4-mg moxonidine (n=7) or 2.5- to 5.0-mg cilazapril (n=7). Finger nailfold video capillaroscopy was performed at baseline and after 8 weeks of treatment. Blood pressure was measured by conventional office technique. Capillary blood cell velocity, 1 minute after local finger cooling, increased in the Moxonidine group (0.65 +/- 0.53 mm/sec to 1.13 +/- 0.77 mm/sec; p<0.05) after 8 weeks treatment compared to the baseline. The increase in the Cilazapril group from 0.79 +/- 0.45 mm/sec to 0.93 +/- 1.03 mm/sec did not reach a level of statistical significance. Blood pressure decreased from 151 +/- 8/101 +/- 5 to 147 +/- 6/98 +/- 7 mmHg in the Moxonidine group and from 164 +/- 12/102 +/- 6 to 140 +/- 9/93 +/- 9 mmHg in the cilazapril group. Moxonidine increased nailfold capillary blood cell velocity 1 minute after local finger cooling in patients with mild-to-moderate hypertension. This improvement of the peripheral microcirculation may be associated with reversal of vascular dysfunction in hypertension.