Bassiouny H S, Davis H, Massawa N, Gewertz B L, Glagov S, Zarins C K
Department of Surgery, University of Chicago, IL 60637.
J Vasc Surg. 1989 Feb;9(2):202-12.
To identify microanatomic and chemical features that may mark the transition from asymptomatic to symptomatic atherosclerotic carotid lesions, we evaluated 62 carotid artery bifurcation plaques including 45 high-grade stenoses removed at endarterectomy and 17 nonstenotic plaques recovered at autopsy. Morphologic features were evaluated on multiple-interval histologic sections and were graded for the presence of hemorrhage, ulceration, thrombosis, lumen surface irregularity, and calcification. Plaque hemorrhage, recent and remote, was found in most of the specimens, and did not discriminate between symptomatic and asymptomatic stenotic plaques. High-grade carotid stenotic plaques were associated with a significantly higher incidence of ulceration (53%), thrombosis (49%), and lumen irregularity (78%) when compared to nonstenotic asymptomatic plaques (6%, 0%, and 17%, respectively; p less than 0.01). Although these features were more prominent in lesions that produced symptoms, they were present in 80% of the stenotic bifurcations, and did not distinguish between symptomatic and asymptomatic endarterectomy plaques. No significant differences were found between symptomatic and asymptomatic high-grade lesions with respect to collagen, DNA, total cholesterol, fibrinogen, lipase, elastase, or collagenase content. We conclude that intraplaque hemorrhage is commonly seen in carotid plaques even without severe stenosis, and it does not appear to be a dominant determinant of symptoms. Ulceration and surface thrombi that may lead to cerebral embolization are prominent features in markedly stenotic plaques even when symptoms are absent. The disruptive processes that underlie plaque instability appear to be closely associated with plaque size and stenosis rather than plaque composition.
为了识别可能标志着无症状性动脉粥样硬化性颈动脉病变向症状性病变转变的微观解剖和化学特征，我们评估了62个颈动脉分叉处斑块，其中包括45个在动脉内膜切除术中切除的高度狭窄斑块和17个在尸检中发现的无狭窄斑块。在多个间隔的组织学切片上评估形态学特征，并对出血、溃疡、血栓形成、管腔表面不规则和钙化的存在进行分级。在大多数标本中都发现了近期和远期的斑块出血，并且它并不能区分有症状和无症状的狭窄斑块。与无症状的无狭窄斑块相比（分别为6%、0%和17%；p小于0.01），高度颈动脉狭窄斑块的溃疡发生率（53%）、血栓形成发生率（49%）和管腔不规则发生率（78%）显著更高。尽管这些特征在产生症状的病变中更为突出，但它们在80%的狭窄分叉处都存在，并且不能区分有症状和无症状的动脉内膜切除术斑块。在有症状和无症状的高度病变之间，关于胶原蛋白、DNA、总胆固醇、纤维蛋白原、脂肪酶、弹性蛋白酶或胶原酶含量未发现显著差异。我们得出结论，即使没有严重狭窄，斑块内出血在颈动脉斑块中也很常见，并且它似乎不是症状的主要决定因素。即使没有症状，可能导致脑栓塞的溃疡和表面血栓也是明显狭窄斑块的突出特征。斑块不稳定背后的破坏过程似乎与斑块大小和狭窄密切相关，而不是与斑块成分相关。
