冠状动脉分叉病变斑块分布特点的血管内超声研究

目的:应用血管内超声(IVUS)研究冠状动脉分叉病变处斑块分布特点。方法:研究入选45例患者52处分叉病变,根据分支发出的部位将主支血管四等分,比较四个象限的斑块面积和面积百分比,采用逐步回归分析确定影响斑块分布位置的因素,应用重塑指数和血管代偿比率评估主支血管分叉近端和远端的血管重塑模式。结果:主支血管分叉近端斑块偏心指数明显低于主支血管分叉远端(1.86±0.64vs9.52±2.78,P<0.05)。主支血管分叉近端斑块面积在四个象限内无明显区别(2.31±1.05)mm2vs(2.46±0.97)mm2vs(2.24±0.98)mm2vs(2.44±1.05)mm2(P>0.05),主支血管分叉远端斑块面积在分支对侧管壁明显大于分支侧[(2.61±1.20)mm2,(2.66±1.85)mm2vs(0.74±0.66)mm2,(0.68±0.58)mm2]。主支血管分叉远端斑块与分支的角度和分叉角度正相关(R=0.793,R2=0.628)。主支血管分叉近端血管重塑指数(1.05±0.10vs0.94±0.08,P<0.05)和血管代偿比率[0.07±0.15vs-(0.17±0.26),P<0.05]明显大于主支血管分叉远端。结论:分叉病变主支血管分叉两侧斑块分布和血管重塑模式明显不同。主支血管分叉近端血管多呈正性重塑,斑块呈向心性360°环周分布。主支血管分叉远端血管多为负性重塑,斑块分布呈偏心性,主要分布在分支开口的对侧管壁,斑块相对于分支开口的角度与分叉角度正相关,分叉角度接近直角时,斑块分布在分支开口的对侧壁(180°±),分叉角度为锐角时,斑块分布在分支开口的旁侧壁(90°±和270°±)。

Characteristics of Atherosclerotic Plaque Distribution in Coronary Artery Bifurcation:An Intravascular Ultrasound Study

Objective:To investigate atheroma distribution at coronary bifurcation by intravascular ultrasound.Methods:Fifty-two coronary bifurcation lesions in 45 patients were enrolled in our study.We quartered main vessel lumen according to the site of side branch and measured plaque area and area percent of each quadrant.We analyzed influential factors with angle of plaque center and branch vessel by step regression.Vessel remodeling was evaluated by remodeling index and vessel compensation ratio.Results:Eccentric indexes were smaller in proximal segment than distal segment.Plaque area and area percent was no difference among each quadrant in proximal segment,but in distal segment,plaque area and area percent was larger in opposite wall than in the same wall of side branch ostial.The angle between plaque center and side branch was correlated with the side branch take-off angle positively.Remodeling index and vessel compensation ratio were larger in proximal segment than distal segment.Conclusion:Proximal segment of coronary bifurcation demonstrated concentric plaque and negative remodeling.Distal segment demonstrated eccentric plaque and positive remodeling,plaque accumulated opposite to the flow divider.Plaque accumulated in the opposite wall when side branch took off by straight angle.Conversely,plaque accumulated in the lateral wall when side branch took off by acute angle.