组织二尖瓣环位移与纵向应变评价左心室长轴收缩功能

摘要

Objective To evaluate the value of tissue motion tracking of mitral annular displacement (TMAD) method and longitudinal strain in the assessment of longitudinal systolic function of left ventricule in healthy subjects.Methods Forty healthy subjects were enrolled in this study .Left ventricular end-diastolic dimension(LVEDd),left ventricular end-systolic volume ( LVESV),left ventricular end-diastolic volume( LVEDV) and left ventricular ejection fraction ( LVEF) were measured by using two-dimensional echocardiography.The maximal displacement of the six points (anteroseptal,lateral,inferior,anterior,posterior and septal regions ) on mitral annulus ( Ds) and peak systolic longitudinal strain of 18 segments were measured.The average value of left ventricular longitudinal strain in 18 segments was taken as global longitudinal strain(GLS).The correlation between mean displacement (MDS) and LVEF,GLS and LVEF,MDS and GLS were analyzed.Results The systolic displacements of mitral annulus at anteroseptal,lateral, inferior,anterior,posterior and septal regions were (12.37 ±2.05)cm,(12.94 ±2.85)cm,(12.79 ±2.48)cm, (12.97 ±2.29)cm,(12.33 ±2.34)cm and (11.59 ±1.99)cm respectively.But the differences were not statistically significant among six points (F =2.245,P =0.051).The left ventricular systolic GLS was gradually increasing from base to apex.But the differences were not statistically significant among different segments(F=2.988,1.902,2.379,3.164,1.278,0.044,all P>0.05).Also,the systolic peak GLS was significantly different among different segments at the same level (F=2.871,2.752,1.560,all P>0.05).A good correlation was showed between TMAD [(12.67 ±1.57) cm] and LVEF[(57.98 ±4.37)%],GLS [(21.81 ±2.61) cm] and LVEF,and TMAD and GLS ( r =0.853, -0.75, -0.72,all P <0.01). Conclusions The significant correlations were found among two-dimensional strain,TMAD and LVEF by two-dimensional ultrasound speckle tracking technology .Sampling in mitral annulus is simple, fast and non-angle-dependent.TMAD is expected to become a new method to evaluate global left ventricular systolic function.%　　目的探讨定量组织运动二尖瓣环位移（TMAD）技术及左心室心肌的纵向应变在评价健康人左心室长轴收缩功能中的价值。方法选取健康志愿者40名，二维测量左心室舒张末期内径、舒张末期容积、收缩末期容积和左心室射血分数（LVEF）。测量二尖瓣环6个位点（前间隔、侧壁、下壁、前壁、后壁、后间隔）的收缩期最大位移（Ds）及左心室各节段纵向应变收缩期峰值，左心室各节段纵向应变收缩期峰值平均值为左心室整体纵向应变（GLS），并分析平均Ds及左心室GLS与简化双平面Simpson法测得的LVEF的相关性。结果二尖瓣环前间隔位移为（12．37±2．05）cm，侧壁位移为（12．94±2．85）cm，下壁位移为（12．79±2．48） cm，前壁位移为（12．97±2．29） cm，后壁位移为（12．33±2．34）cm，后间隔位移为（11．59±1．99）cm，二尖瓣环6个位点位移比较差异无统计学意义（F＝2．245，P＝0．051）。从基底部到心尖部左心室不同节段（前间隔、前壁、侧壁、后壁、下壁、后间隔）纵向应变收缩期峰值基本呈现逐步递增的趋势，但差异均无统计学意义（F＝2．988、1．902、2．379、3．164、1．278、0．044，P均＞0．05）；基底部、中部、心尖部同一水平不同节段纵向应变收缩期峰值差异亦均无统计学意义（F＝2．871、2．752、1．560，P均＞0．05）。二尖瓣环6个位点平均Ds为（12．67±1．57）cm，与简化双平面Simpson法测得的LVEF［（57．98±4．37）％］呈显著正相关（r＝0．853，P＜0．01）；左心室GLS为（－21．81±2．61）cm，与LVEF呈显著负相关（r＝－0．75，P＜0．01）；二尖瓣环6个位点平均Ds与左心室GLS呈显著负相关（r＝－0．72，P＜0．01）。结论应用二维斑点追踪技术测定的二维应变及TMAD与LVEF存在显著相关性，二尖瓣环取点简便、快捷、无角度依赖，TMAD有望成为定量评价左心室收缩功能的新方法。