血管内超声对不稳定斑块处血管重构的实验研究

目的明确血管内超声(IVUS)不稳定斑块的血管重构特点。方法通过转染p53基因建立动脉粥样硬化不稳定斑块的兔模型。应用IVUS分别观察测量腹主动脉同一血管段中破裂斑块与未破裂斑块处血管的外弹力膜面积(EEMA)、管腔面积(LA)、斑块面积(PA)及管腔面积狭窄率,计算斑块处血管的重构指数(RI)。通过比较两组的RI,明确不稳定斑块的血管重构特点。结果与未破裂斑块相比较,破裂斑块的EEMA、PA及管腔面积狭窄率明显大于前者,具有显著的统计学意义(P<0.01),破裂斑块呈现明显的正性重构,占80%(16/20),而稳定斑块主要为负性重构,占70%(14/20)。结论IVUS应用于已建立的AS不稳定斑块动物模型上,发现AS不稳定斑块处血管呈现明显的正性重构,正性重构是不稳定斑块突出的特征之一。

Arterial Remodeling of Unstable Atherosclerotic Plaques with Intravascular Ultrasound an Experimental Study

Objective To identify the arterial remodeling pattern of unstable atherosclerotic plaques with intravascular ultrasound (IVUS).Methods Unstable animal models were duplicated by transferred p53 genes.IVUS was used to measure the external elastic membrane area (EEMA),lumen area(LA),plaque area(PA) and lumen area narrowing (%) of plaque ruptured and nonruptured group,respectively,and arterial remodeling index was calculated.The arterial remodeling pattern of unstable atherosclerotic plaques was derived by comparing the results of IVUS in the ruptured and non-ruptured plaques.Results The EEMA,LA,PA and lumen area narrowing in the ruptured plaques were larger than those of non-ruptured plaques (P<0.01).Positive remodeling pattern was observed in ruptured plaques and accounted for 80%(16/20),while non-ruptured plaques showed negative remodeling which was responsible for 70%(14/20).Conclusions Using our animal models of unstable atherosclerotic plaques,IVUS reveals that unstable atherosclerotic plaques mainly show positive remodeling,which is a prominent feature of plaques vulnerable to rupture.