组织多普勒及应变率成像技术对二尖瓣狭窄患者右心室收缩功能的评价

Assessment of right ventricular systolic function in patients with mitral stenosis using tissue Doppler imaging and strain rate imaging

关键词:  组织多普勒  应变  应变率  二尖瓣狭窄  右心室功能  超声心动图

Key words:  [Key words]　tissue Doppler imaging  strain  strain rate  mitral stenosis  right ventricular function  echocardiography

摘要:

目的　 应用组织多普勒（TDI）及应变率成像（SRI）技术评价无右心衰症状的二尖瓣狭窄（MS）患者的右心室（RV）整体及局部心肌收缩功能。方法　单纯性MS患者40例，健康对照组20例。测量左心房前后径（LAD）、肺动脉收缩压（PASP），描记二尖瓣口面积（MVA），M型超声测量三尖瓣环的收缩期位移（TAPSE），计算右室面积变化率（RVFAC）。应用TDI技术测量三尖瓣环收缩期速度（Tric-s），等容收缩期速度（IVV），等容收缩期加速度（IVA）。SRI测量右心室游离壁（RVFW）及室间隔的收缩期应变（S）及应变率（SR），RVFW及室间隔的S及SR的均值作为RV整体长轴的S和SR。并将S和SR与PASP进行相关性分析。结果　与对照组相比，MS组的LAD及PASP明显增高（P<0.01）。MS组的TAPSE及Tri-s、IVV、IVA明显低于对照组（P<0.01或P<0.05）。RV长轴整体S及SR，RVFW基底段及中段的S及SR，室间隔基底段S明显低于对照组（P<0.05或P<0.01），室间隔中段S及室间隔各段SR在两组间无差别。RV长轴整体S、SR均与PASP呈负相关，相关系数分别为 r=-0.71，r=-0.59（P均<0.05）。结论　应用TDI及SRI技术可以早期发现MS患者RV整体及局部功能的受损情况。

Abstract:

[Abstract] Objective　To investigate the global and regional longitudinal systolic function of right ventricle (RV) using tissue Doppler imaging （TDI ）and strain rate imaging （SRI） in mitral stenosis (MS) patients without clinical symptoms of right heart failure. Methods　Conventional echocardiography and TDI, SRI analysis were performed in 40 MS patients and 20 normal subjects. left atrial end-systolic diameter (LAD), pulmonary artery systolic pressure (PASP) were measured. End-diastolic and end-systolic areas of RV were measured from the apical four-chamber view to calculate RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPS) was determined in apical four-chamber view. Parameters derived from TDI and SRI included tricuspid annulus S-wave velocity (Tric-s), peak isovolumic contraction velocity （IVV） and myocardial acceleration during isovolumic contraction （IVA）, longitudinal systolic strain (S) and strain rate (SR) of right ventricular free wall (RVFW) and septum. The average of RVFW and septum S, SR were defined as the whole S, SR of RV. Correlation between S, SR and PASP were analyzed. Results　Compared with normal subjects, LAD and PASP were significantly higher in patients with MS (P<0.01), TAPSE and Tric-s （IVV） and （IVA） were significantly lower in MS patients (P<0.01 or P<0.05). S and SR of the global RV and all segments of RVFW were significantly reduced in MS patients (P<0.05 or P<0.01), regional longitudinal S was significantly reduced in the basal septum (P<0.05). Correlation analysis indicated a significant relationship between the PASP and global S, SR of RV. Conclusion　RV global and regional systolic function evaluated by TDI and SRI analysis in patients with MS has shown decreased before right heart failure.