The Importance of Hemorrhage in the Relationship Between Gross Morphologic Characteristics and Cerebral Symptoms in 376 Carotid Artery Plaques

Abstract

In a prospective study 376 carotid artery plaques (275 symptomatic, 101 asymptomatic) were obtained from endarterectomies (184 unilateral and 96 bilateral) in 280 patients. The gross morphologic features of each plaque were noted at surgery and, together with the patient's clinical history, stored in computer memory. These data were analyzed in order to investigate the relationship of gross morphologic plaque characteristics with both the presence of cerebral symptoms and the degree of stenosis associated with the plaque. Ulceration was the most frequently observed of the five major gross plaque morphologic characteristics (46.0% of all plaques), but only intramural hemorrhage (30.6% of all plaques) was significantly more common in all symptomatic compared with all asymptomatic plaques (p less than 0.02). Hemorrhage was also the only gross characteristic significantly more common in focal symptomatic plaques when compared with either asymptomatic plaques (p less than 0.05) or nonfocal symptomatic plaques (p less than 0.01). When all the plaques were divided into three broad degrees of stenosis groups (0-39%, 40-69%, 70-99%) on the basis of angiographic data, only hemorrhage showed a significant correlation in incidence with increased degree of plaque stenosis, both when all plaques were considered (p less than 0.001) and when only symptomatic plaques were examined (p less than 0.001). The results indicate that intramural hemorrhage is the only carotid plaque gross morphologic characteristic significantly more frequent in symptomatic compared with asymptomatic plaques and the only characteristic significantly correlated with increased plaque size. These findings indicate that factors other than plaque ulceration and intraluminal thrombus play an important role in carotid plaque related cerebral symptoms. The data also raise questions concerning the unequivocal value of anticoagulant therapy in carotid artery disease, especially in highly stenotic lesions.

Relationships of Cerebral MRI Findings to Ultrasonographic Carotid Atherosclerosis in Older Adults

“…2 Given the strong and consistent relationships of MRI abnormalities to severity of carotid atherosclerosis, the question arises whether there are other ultrasound-definable characteristics of carotid disease that are related to MRI abnormalities. Clinical studies of carotid atherectomy specimens suggest that ulcerated, 20 less organized, 15 and hemorrhagic 21,22 plaques are associated with symptoms. Some of these associations have been disputed, however, with other investigators failing to demonstrate more frequent symptoms associated with ulcerations 14,21 and plaque hemorrhage.…”

“…Clinical studies of carotid atherectomy specimens suggest that ulcerated, 20 less organized, 15 and hemorrhagic 21,22 plaques are associated with symptoms. Some of these associations have been disputed, however, with other investigators failing to demonstrate more frequent symptoms associated with ulcerations 14,21 and plaque hemorrhage. 23,24 The documented ability of B-mode ultrasonographic scanning to detect plaque ulceration, 25 heterogeneity, 26,27 and hemorrhage, 28 though disputed by some, 24,29,30 has led to the demonstration that these ultrasound-defined characteristics are also associated with ipsilateral neurologic symptoms, 31 clinical events, 26 and MRI-defined infarcts.…”

Multidetector-Row Computed Tomography in Evaluation of Atherosclerotic Carotid Plaques Complicated with Intraplaque Hemorrhage

“…13,14 Atherosclerotic carotid plaques complicated with intraplaque hemorrhage (AHA type VIb) are considered as unstable and are associated with a higher incidence of 3 cerebrovascular events. 12,[15][16][17] Computed tomography (CT) angiography demonstrated high accuracy in diagnosing carotid artery stenosis. [18][19][20][21][22] Additional feature of computed tomography is its ability to measure tissue density (expressed as a number of Hounsfield units [HU]).…”

Carotid Atherosclerotic Calcification Does Not Result in High Signal Intensity in MR Imaging of Intraplaque Hemorrhage

“…10,11 For decades, IPH has been thought to play a role in the progression of atherosclerosis. [12][13][14][15] However, recent studies have clarified its importance. 16 The rapid and excessive accumulation of red blood cells in the plaque promotes lipid deposition and enlargement of the necrotic core, which is believed to be a pro-atherogenic stimulus.…”