Methods: Morphologic characteristics of coronary arteries in eight women with myocardial infarction and angiographically normal or not significantly stenosed vessels were investigated with intracoronary ultrasound. The infarct-related vessel was assessed by three-dimensional volumetric analysis and compared with a control vessel from a noninfarcted area.
Results: Atherosclerosis was found in all infarct-related arteries. The plaques were predominantly soft, eccentric, poorly calcified, and with little lipid pools or none at all. Although the average area and thickness of plaques and cross-sectional narrowing of the infarct-related arteries were greater than those of control arteries, there were no pathognomonic characteristics of plaques in the infarct-related vessels.
Conclusion: The possibility that atherosclerosis is the main etiologic factor for myocardial infarction can not be excluded even for women without an angiographically obvious coronary stenosis in the infarct-related vessels.