房缩期二尖瓣前向血流速度联合二尖瓣环纵向位移评估左室僵硬度

Assessment of Left Ventricular Stiffness Using Anterior Mitral Flow Velocity Combined with Longitudinal Dis⁃placement of Mitral Annulus by Shear Wave Elastography During Atrial Systole

目的:探索房缩期二尖瓣前向血流速度联合二尖瓣环纵向位移评估左室僵硬度的可行性。方法:募集门诊接受经胸超声心动图检查的志愿者117例。超声心动图测量常规参数,描计组织多普勒a波的速度时间积分记作VTIa′,计算A2/VTIa′。将受试者分为舒张功能正常组(GROUP 1,n=35)、舒张功能障碍I级组(GROUP 2,n=61)、舒张功能障碍Ⅱ级及Ⅲ级组(GROUP 3,n=21),对比三组间A2/VTIa′及其他参数差异;行A2/VTIa′与现有僵硬度参数、僵硬度影响因素的相关性分析;将GROUP 1与GROUP 2归为僵硬度正常组(NS),GROUP 3归为僵硬度异常组(AS),分析A2/VTIa′鉴别两组的诊断效能。结果:舒张功能不同分组间A2/VTIa′差异存在显著统计学意义(P<0.001);A2/VTIa′与LVEDP/LVEDV、KLV分别呈中度、低度正相关(r=0.411、0.222,P<0.05),与年龄、收缩压、E/e′分别呈低度正相关(r=0.364、0.338、0.356,P<0.001),与e′呈低度负相关(r=-0.365,P<0.001);A2/VTIa′鉴别AS与NS的AUC为0.805,诊断敏感度和特异度分别为81.0%和66.7%。结论:A2/VTIa′可用于评估左室僵硬度,且对僵硬度异常的鉴别价值高于目前左室僵硬度评估指标。

Objective To investigate the feasibility of anterior mitral flow velocity combined with the longitudinal displace⁃ment of mitral annulus during atrial systole to assess left ventricular stiffness.Methods A total of 117 volunteers who under⁃went transthoracic echocardiography at the outpatient clinic were enrolled.Conventional echocardiographic parameters were measured,and the velocity-time integral(VTI)of the tissue Doppler a-wave,denoted as VTIa′,was calculated to derive A2/VTIa′.Subjects were categorized into three groups:normal diastolic function group(GROUP 1,n=35),grade I dias⁃tolic dysfunction group(GROUP 2,n=61),and gradeⅡ&Ⅲdiastolic dysfunction group(GROUP 3,n=21).The differences in A2/VTIa′and other parameters among the groups were analyzed alongside correlational assessments with known stiffness parameters and influencing factors of stiffness.GROUP 1 and GROUP 2 were collectively termed the normal stiffness group(NS),and GROUP 3 was designated as the abnormal stiffness group(AS)to analyze the diagnostic per⁃formance of A2/VTIa′.Results Significant differences in A2/VTIa′were observed across the groups(P<0.001).A2/VTIa′exhibited a moderate-to-low positive correlation with LVEDP/LVEDV and KLV(r=0.411,0.222,P<0.05),a low positive correlation with age,systolic blood pressure,and E/e′(r=0.364,0.338,0.356,P<0.001),and a negative correla⁃tion with e′(r=-0.365,P<0.001).The AUC of A2/VTIa′for distinguishing AS from NS was 0.805,with a diagnostic sensitivity of 81.0%and specificity of 66.7%.Conclusion A2/VTIa′proves to be a valuable measurement for evaluating left ventricular stiffness.Its diagnostic utility in identifying abnormal stiffness surpasses that of existing left ventricular stiff⁃ness assessment methods.