Cholesterol reduction improves myocardial perfusion abnormalities in patients with coronary artery disease and average cholesterol levels

OBJECTIVES We sought to evaluate whether pravastatin treatment increases my ocardial perfusion, as assessed by thallium-201 single-photon emission comp uted tomographic (SPECT) dipyrid-amole testing, in patients with coronary a rtery disease (CAD) and average cholesterol levels. BACKGROUND Previous studies in hypercholesterolemic patients hale demonstra ted that cholesterol reduction restores peripheral and coronary endothelium -dependent vasodilation and increases myocardial perfusion. METHODS This was a randomized, placebo-controlled study with a cross-over d esign. Twenty patients with CAD were randomly assigned to receive 20 mg of pravastatin or placebo for 16 weeks and then were crossed over to the oppos ite medication for a further 16 weeks. Lipid and lipoprotein analysis and d ipyridamole thallium-201 SPECT were performed at the end of each period. Th e SPECT images were visually analyzed in eight myocardial segments using a 4-point scoring system by two independent observers. A summed stress score and a summed rest score were obtained for each patient. Quantitative evalua tion was performed by the Cedars-Sinai method. The magnitude of the defect was expressed as a percentage of global myocardial perfusion. RESULTS Total and low density lipoprotein cholesterol levels during placebo were 214 +/- 29 mg/dl and 148 +/- 25 mg/dl, respectively. These levels wit h pravastatin were 170 +/- 23 mg/dl and 103 +/- 23 mg/dl, respectively. The summed stress score and summed rest score were lower with pravastatin than with placebo (7.2 +/- 2.3 vs. 5.9 +/- 2.3, p = 0.012 and 3.2 +/- 1.6 vs. 2 .4 +/- 2.2, p = 0.043, respectively). Quantitative analysis showed a smalle r perfusion defect with pravastatin (29.2%) as compared with placebo (33.8% ) (p = 0.021) during dipyridamole stress. No differences were found at rest . CONCLUSIONS Reducing cholesterol levels with pravastatin in patients with C AD improves myocardial perfusion during dipyridamole stress thallium-201 SP ECT. (C) 1999 by the American College of Cardiology.