MSCT评价心动周期中主动脉瓣环动态变化

MSCT evaluation on dynamic changes of aortic annulus during cardiac cycle

目的采用MSCT探讨主动脉瓣环(AA)在心动周期中的动态变化特点及其与瓣环钙化的关系。方法收集接受MSCT扫描的69例主动脉瓣狭窄患者(AS组)及69名志愿者(正常对照组),于收缩期和舒张期测量AA长径、短径、面积及周长,分析各瓣环径变化特点及其与钙化积分的相关性,对比不同钙化级别瓣环的运动差异。结果 2组收缩期各瓣环径均大于舒张期(P均<0.001),椭圆指数小于舒张期(P<0.001),AS组与正常对照组收缩期各瓣环径差异无统计学意义(P均>0.05)。AS组AA周长衍生直径(DP)在收缩期及舒张期均大于面积衍生直径(DA,P均<0.001),AA面积相对变化率显著高于周长相对变化率(P<0.001)。AA钙化积分与心动周期中DA、Dp变化量呈负相关(r=-0.264、-0.302,P均<0.05)。瓣环不同级别钙化的各参数变化量差异均有统计学意义(P均<0.05)。结论 AA形态与结构在心动周期中变化显著,重度钙化AA动态变化显著降低。测量收缩期参数可为经导管主动脉瓣置换术提供准确的解剖学数据。

Objective To explore the dynamism of aortic annulus(AA)during cardiac cycle and the correlation with calcification with MSCT.Methods A total of 69 aortic stenosis patients(AS group)and 69 controls(normal control group)underwent MSCT.Dimensions of AA were assessed on both systolic and diastolic phase.For each phase,the long diameter,short diameter,area and perimeter of AA were measured,respectively.The features of annular dimension change and the relationship with calcium score were analyzed.Finally,the differences of dynamic of AA in different calcification grades were compared.Results The mean annular dimensions were significantly larger during systole than diastole(all P<0.001),whereas ellipticity index was significantly lower during diastole than systole in both group(P<0.001).There was no significant difference in the diameters of AA between the two groups during systole(P>0.05).In AS group,the perimeter-derived diameter(D P)of AA was significantly larger than the area-derived diameter(D A)in both systolic and diastolic phase(P<0.001).The change rate of AA area was significantly higher than change rate of perimeter(P<0.001)during cardiac cycle.There were negative correlation between the calcium score of AA and the change of D A and D p(r=-0.264,-0.302,P<0.05).The dynamic of AA had significant difference among different calcification grades(P<0.05).Conclusion The morphology and structure of AA significantly changed during cardiac cycle,and the dynamic change of AA with severe calcification significantly reduced.Systolic multiparameter measurement might provide accurate anatomical data for transcatheter aortic valve replacement.