三维超声心动图定量评价退行性二尖瓣反流瓣环动态变化

Quantitative evaluation of the dynamic changes of mitral annulus in patients with degenerative mitral regurgitation by three-dimensional echocardiography

目的应用经胸三维超声心动图定量分析退行性二尖瓣反流(DMR)患者二尖瓣环(MA)静态几何结构及动态变化。方法选取2019年8月至2021年3月于云南省阜外心血管病医院就诊的35例DMR(均为二尖瓣脱垂和Barlow样改变)患者作为DMR组,选取同期健康志愿者42例作为对照组。所有研究对象均在舒张晚期、收缩早期、收缩中期和收缩晚期定量测量二尖瓣环面积(MAA)、二尖瓣环周长(MAP)、二尖瓣环前外后内侧直径(DALPM)、二尖瓣环前后径(DAP)、二尖瓣非平面角(NPA)、二尖瓣环高度(AH)以及瓣环高度与联合间径的比值(AHCWR),并计算以上各参数的收缩期变化分数。比较两组间MA静态结构和动态变化差异,分析两组MA在整个心动周期内的动态变化特点。结果静态结构:DMR组整个心动周期内MAA、MAP、DAP和DALPM较对照组增大,差异有统计学意义(均P<0.05);DMR组收缩中期和晚期鞍形结构较对照组扁平(AHCWR:0.17±0.01比0.21±0.01,0.15±0.01比0.23±0.01;均P<0.05),其余时相鞍形结构相对保留。动态变化:对照组舒张晚期至收缩早期出现收缩前收缩(MAA、MAP、DAP、DALPM减小,均P<0.05),鞍形加深(NPA减小,AH和AHCWR增大,均P<0.05);与对照组相比,DMR组MA收缩前收缩和鞍形加深均消失(舒张晚期与收缩早期所有MA参数差异无统计学意义,均P>0.05);DMR组收缩期动态变化也较对照组减弱受损,表现为DALPM、NPA及AHCWR收缩期变化分数小于对照组(均P<0.05),除DAP外,其余MA参数4个时相差异无统计学意义(均P>0.05)。结论正常人MA鞍形结构明显,且MA在心动周期内动态变化显著,出现明显的收缩前收缩,鞍形加深现象。DMR患者MA明显增大,且MA鞍形结构在收缩中晚期扁平化。DMR患者整个心动周期内MA动能均减弱,收缩前收缩现象消失,收缩期动态变化也不同程度受损。

Objective To quantitatively analyze the static geometric structure and dynamic changes of the mitral annulus(MA)in patients with degenerative mitral regurgitation(DMR)by three-dimensional transthoracic echocardiography.Methods Thirty-five patients with DMR(both mitral valve prolapse and Barlow)were collected as DMR group in Yunnan Fuwai Cardiovascular Disease Hospital from August 2019 to March 2021,and 42 healthy volunteers were selected as control group during the same period.The mitral annulus area(MAA),mitral annulus perimeter(MAP),mitral annulus anterolateral-posteromedial diameter(DALPM),anteroposterior diameter(DAP),non-planar angle(NPA),mitral annulus height(AH),and the ratio of height to intercommissural diameter(AHCWR)were measured during the late-diastole,early-systole,mid-systole and late-systole,and the systolic change fractions of the above parameters were calculated.The differences of static structure and dynamic change of MA between the two groups were compared,and the characteristics of dynamic change of MA in the whole cardiac cycle were analyzed.Results Static structure:MAA,MAP,DAP and DALPM in DMR group were higher than those in control group during the whole cardiac cycle,and the differences were statistically significant(all P<0.05).Compared with the control group,the saddle structure in DMR group were flattened in the middle and late contraction stages(AHCWR:0.17±0.01 vs 0.21±0.01 and 0.15±0.01 vs 0.23±0.01,both P<0.05),while the saddle structure was relatively preserved in the rest of the contraction stage.Dynamic changes:Presystole contraction(MAA,MAP,DAP,DALPM decreased,all P<0.05)were appeared durng the late-diastole and early-systole in the control group,and saddle shape deepened(NPA decreased,AH and AHCWR increased,all P<0.05).Compared with the control group,presystole MA contraction and saddle deepening disappeared in DMR group(there were no significant differences in all MA parameters between late-diastole and early-systole,all P>0.05).The systolic dynamic changes were weaker and impaired when compared with the control group,which showed that the systolic change scores of DALPM,NPA and AHCWR were lower than those of the control group(all P<0.05).There were no statistical differences in the 4 time phases of MA parameters except DAP(all P>0.05).Conclusions The saddle-shape structure of MA in normal subjects is obvious,and the dynamic change of MA in the cardiac cycle is significant,with obvious contraction before contraction and saddle-shape deepening.The saddle structure of DMR patient is flattened in the middle and late systolic period,and the MA kinetic energy of DMR patient is weakened throughout the cardiac cycle,the contraction phenomenon disappeared before contraction,and the dynamic change of systolic period is impaired to varying degrees.