Cholesterol-lowering treatment is associated with improvement in coronary vascular remodeling and endothelial function in patients with normal or mildly diseased coronary arteries

Coronary vascular remodeling and altered endothelial function have been des cribed in the early stages of native atherosclerosis. The purpose of this s tudy was to evaluate the association between cholesterol-lowering therapy a nd coronary vascular remodeling and endothelial function in patients with n ormal or mildly diseases coronary arteries. Patients (N=101) with normal or mildly diseased coronary arteries by coronary angiography underwent intrav ascular ultrasound examination of the left anterior descending coronary art ery. Vessel and lumen area, atherosclerotic plaque area, and plaque morphol ogy were evaluated. Vascular reactivity was examined with the use of intrac oronary adenosine, acetylcholine, and nitroglycerin. Patients were divided into 3 groups based on the total cholesterol levels: group 1 (n=25), patien ts with a history of hypercholesterolemia adequately treated (total cholest erol <240 mg/dL); group 2 (n=26), patients with hypercholesterolemia not ad equately controlled (total cholesterol greater than or equal to 240 mg/dL); and group 3 (n=50), patients without hypercholesterolemia. Vessel area and lumen area were significantly greater in groups 1 and 3 than in group 2 (f or respective values in groups 1, 2, and 3: vessel area 11.9+/-0.5, 10.6+/- 0.4, and 11.8+/-0.4 mm(2), both P<0.05; lumen area 8.3+/-0.4, 6.9+/-0.3. an d 8.9+/-0.3 mm(2), both P<0.01). However, plaque areas in groups 1 and 2 we re similar. Furthermore, acetylcholine-induced percent increases in coronar y blood flow were significantly greater in groups 1 and 3 than in group 2 ( for respective values in groups 1, 2, and 3: 70.5+/-20.1%, 22.8+/-13.7%, an d 68.6+/-14.8%, both P<0.05). Cholesterol-lowering treatment is associated with an improvement in coronary lumen area that results not from a decrease in plaque area but from an increase in vessel area, reflecting vascular re modeling. Additionally, this adaptive process may occur in association with an improvement of endothelium-dependent vasodilation of the resistance cor onary artery.