Improvement of endothelial function in patients with hypercholesterolemia and normal coronary arteries with lipid-lowering therapy

Introduction and aims. In patients with coronary risk factors the presence of endothelial dysfunction in epicardial arteries has been documented. The purpose of this study was to determine whether endothelial dysfunction, doc umented hypercholesterolemic patients and angiographycally normal coronary arteries, improves by reduction and normalization of lipid levels. Patients and method. In 10 patients with hypercholesterolemia and normal co ronary angiography, the endothelium-dependent coronary vasomotion was studi ed by intracoronary infusion of acetylcholine into the left anterior descen ding coronary artery. Vasomotion changes in response to acetylcholine were analized by quantitative angigraphy. Five patients without coronary risk fa ctors and normal coronary arteries formed the control group. Patients with hypercholesterolemia were treated with lipid-lowering therapy (diet and lov astatin) and endothelial function was reevaluated after 24 +/- 4 months. Results. In the initial study, hypercholesterolemic patients compared with the control group showed a vasocontrictor response to serial doses of acety lcholine (10(-6) M, 10(-5) M, 10(-4) M) indicative of endothelial dysfuncti on (study group: -0.3 +/- 10%, -6 +/- 4%, -18 +/- 10% vs control group: -0. 6 +/- 6%, -2 +/- 6%, 3 +/- 6%; p < 0.01 to 10(-4) M acetylcholine dose). Du ring follow-up hypercholesterolemic patients showed a significant reduction in total cholesterol levels and LDL. Compared to first study, at follow-up , there was an improvement in the response to acetylcholine (-0.4 +/- 4%, - 3 +/- 6%, -3 +/- 10%; p < 0.001 vs basal values at 10-4 M acetylcholine con centration). Reduction in total cholesterol during follow-up was related to the improvement in the vasoconstrictor response to acetylcholine (r = 0.53 ; p < 0.05). Conclusion. In patients with hypercholesterolemia and angiographycally norm al coronary arteries with documentated endothelial dysfunction, the reducti on and normalization of lipid levels during follow-up may improve endotheli um-dependent coronary vasomotion.