Clinical relevance of intraplaque hemorrhage in the internal carotid artery.

In this study the correlation between hemispherical ischemic symptoms and the presence of intraplaque hemorrhage in carotid plaques has been evaluated. 38 patients who had undergone carotid endarterectomy were examined clinically and the specimens obtained from operation were studied morphologically. The patients were divided into two groups, asymptomatic and symptomatic regarding the territory of the supplying carotid artery. The presence of intraplaque hemorrhage, shown by Ladewig's Trichrom stain, as well as evidence of iron, immunohistochemical stain of hemoglobin and native fluorescence microscopy was noted, and, according to their extension, classified into three degrees. As a result, there was neither a correlation between history of ischemic brain symptoms and the presence of intraplaque hemorrhage, nor between clinical symptoms and extension of hemorrhage. The plaques were high degree stenotic (greater than 80%) in most of the patients and showed various degenerative changes. In 97% of all plaques with hemorrhages surface defects were seen. Our results confirm that intraplaque hemorrhage is one out of a series of pathological events which occurs during advanced atherosclerosis. Blood inflow from the lumen through an already damaged plaque surface is a common event and a correlation with the onset of symptoms is unlikely.