Improvement of Impaired Myocardial Vasodilatation Due to Diffuse Coronary Atherosclerosis in Hypercholesterolemics After Lipid-Lowering Therapy

Background—Diminished myocardial vasodilatation (MVD) in hypercholesterolemics without overt coronary stenosis has been reported. However, whether the diminished MVD of angiographically normal coronary arteries in hypercholes-terolemics can be reversed after lipid-lowering therapy is not known. Methods and Results—A total of 27 hypercholesterolemics and 16 age-matched controls were studied. All patients had.1 normal coronary artery, and those segments that were perfused by anatomically normal coronary arteries were studied. Myocardial blood flow (MBF) was measured during dipyridamole loading and at baseline using positron emission tomography and 13N-ammonia, after which MVD was calculated before and after lipid-lowering therapy. Total cholesterol was significantly higher in hypercholesterolemics (263633.8) than in controls (195616.6), and it normalized after lipid-lowering therapy (197619.9). Baseline MBF (ml z min21 z 100 g21) was comparable among hypercholesterolemics (both before and after therapy) and controls. MBF during dipyridamole loading was significantly lower in hypercholesterolemics before therapy (189675.4) than in controls (2996162