EFFECT OF ANTIHYPERTENSIVE TREATMENT ON SMALL ARTERIES OF PATIENTS WITH PREVIOUSLY UNTREATED ESSENTIAL-HYPERTENSION

In a double-blind randomized trial, the effects of treatment with an a ngiotensin-converting enzyme (ACE) inhibitor (perindopril) and a beta- blocker (atenolol) on small artery structure were compared in previous ly untreated essential hypertensive patients. Subjects (diastolic bloo d pressure greater than or equal to 100 and less than or equal to 120 mm Hg) were randomly assigned to treatment for 12 months with either p erindopril(n=13, 4 to 8 mg/d) or atenolol (n=12, 50 to 100 mg/d); the dosage was adjusted upward and in some cases combined (n=5, perindopri l; n=2, atenolol) with thiazide diuretic to achieve target blood press ure (diastolic blood pressure below 90 mm Hg). Before and at the end o f treatment, gluteal biopsies were taken under local anesthetic; from these biopsies, two small arteries were dissected and mounted on a myo graph for morphometry. The reduction in blood pressure with atenolol ( drop in mean blood pressure 28.4+/-1.8 mm Hg) was greater than with pe rindopril (20.6+/-1.8 mm Hg, P<.05). Perindopril treatment caused an i ncrease in small artery diameter (231+/-14 to 274+/-13 mu m, P<.05) an d a reduction in the ratio of media thickness to lumen diameter (7.94/-0.65% to 5.96+/-0.42%, P<.05), whereas atenolol had no effect (246+/ -114 to 231+/-13 mu m and 7.14+/-0.47% to 6.79+/-0.45%, respectively). The change in small artery morphology caused by perindopril was not a ccompanied by any change in media cross-sectional area, suggesting tha t the change was due to ''remodeling.'' The results support the possib ility that treatment with ACE inhibitors causes a greater normalizatio n of the structure of the resistance vasculature in essential hyperten sive patients than treatment with beta-blockers.