Atherosclerosis impairs flow-mediated dilation of coronary arteries in humans.
Publication/Presentation Date
9-1-1989
Abstract
Studies in animals have suggested that increases in blood flow result in dilation of large arteries by an endothelium-dependent mechanism. Atherosclerosis can impair endothelium-dependent vasodilation to vasoactive agents. The purpose of this study was to determine whether or not large coronary arteries in humans exhibit dilation with increases in blood flow and to test the hypothesis that this response is impaired in the presence of atherosclerosis. Graded concentrations of adenosine were infused into the distal left anterior descending (LAD) coronary artery to test the dilator response of the proximal LAD to increases in blood flow. The proximal LAD was thereby exposed to changes in blood flow, but not directly to adenosine. Ten patients with angiographically smooth proximal LAD segments (group 1) and seven patients with irregularities in the proximal LAD consistent with mild atherosclerosis (group 2) were studied. Infusions of adenosine throughout the range of 0.022 to 2.2 mg/min into the LAD produced a dose-dependent increase in estimated coronary blood flow and a mean increase of 305 +/- 27% at 2.2 mg/min adenosine. At 2.2 mg/min adenosine, a striking difference (p less than 0.001) occurred between the significant flow-mediated dilation of the proximal LAD observed in group 1 (+13.2 +/- 1.3% from 2.63 +/- 0.16 mm, p less than 0.001), and the lack of dilation in group 2 (+1.8 +/- 1.5% from 3.20 +/- 0.17 mm, p = NS), despite a greater increase in coronary blood flow in group 2 (+387 +/- 29%) than in group 1 (+230 +/- 36%).(ABSTRACT TRUNCATED AT 250 WORDS)
Volume
80
Issue
3
First Page
458
Last Page
465
ISSN
0009-7322
Published In/Presented At
Cox, D. A., Vita, J. A., Treasure, C. B., Fish, R. D., Alexander, R. W., Ganz, P., & Selwyn, A. P. (1989). Atherosclerosis impairs flow-mediated dilation of coronary arteries in humans. Circulation, 80(3), 458–465. https://doi.org/10.1161/01.cir.80.3.458
Disciplines
Medicine and Health Sciences
PubMedID
2527643
Department(s)
Department of Medicine
Document Type
Article