INTRAVASCULAR ULTRASONIC EVIDENCE BY CONSTANT CROSS-SECTIONAL AREA OFATHEROSCLEROTIC PLAQUES DURING CORONARY VASOMOTION IN HUMANS

Aims This study aims to visualize ultrasonically deformation of athero sclerotic plaques in human coronary arteries during vasoconstriction a nd vasodilatation. Methods and results Intravascular ultrasound detect ed occult atherosclerosis in angiographically normal coronary arteries of eight patients with chest pain at rest. During the acetylcholine p rovocative test, intravascular ultrasound monitored deformation of the atherosclerotic plaques. At the last step of the test, intracoronary injection of isosorbide dinitrate caused vasodilation. Under control, acetylcholine-treated, and isosorbide dinitrate-treated conditions, cr oss-sectional areas of sonolucent circle and vessel lumen were measure d. Subtraction of the latter from the former gave the area of atherosc lerotic plaque. In the process of vasoconstriction and vasodilation, t he plaque area did not change significantly. Conclusion The cross-sect ional area of the atherosclerotic plaque appeared to be constant durin g vasomotion of human coronary arteries.