Evaluation Of Globle And Regional Left Ventricular Myocardial Systolic Function In Patients With Coronary Stenosis By Real-time Three-dimensional Speckle Tracking Imaging Echocardiography

Objective:To quantitatively evaluate left ventricular global and segmental area strain of coronary stenosis patients without regional wall motion abnormality(RWMA) by real-time three-dimensional speckle tracking imaging(RT3D-STI) echocardiography according to coronary artery angiography(CAG),to explore the value of RT3D-STI in the early detection of globle and regional left ventricular myocardial systolic function in coronary stenosis patients without RWMA.Methods:64 objects without RWMA who were enrolled in the study were divided into 2 groups:without coronary stenosis group(n=20) and coronary stenosis group(n=44,one or more coronary stenosis) according to CAG,and all the myocardial segments of objects were divided into 5 groups:without coronary stenosis group normal myocardial segments(n=340,no coronary stenosis),coronary stenosis group normal myocardial segments(n=235,no coronary stenosis), mild coronary stenosis myocardial segments(n=126,coronary stenosis rate1%~<50%), moderate coronary stenosis myocardial segments(n=213,coronary stenosis rate50%~<75%) and severe coronary stenosis myocardial segments(n=174,coronary stenosis rate≥75%).Real-time three-dimensional full volume of left ventricle was obtained,left ventricular global area strain(GAS) and regional area strain(AS) of 17 myocardial segments,left ventricular end-diastolic volume(EDV),end-systolic volume(ESV),left ventricular ejection fraction(LVEF),etc,were measured by RT3D-STI respectively.Gensini score were calculated according to CAG.General parameters and GAS between the two groups were compared with the independent sample t-test,One-way ANOVA was used to analyze AS among the five sub groups,the correlation between GAS and coronary artery Gensini score was analyzed by Pearson correlation analysis,agreement was assessed using the method proposed by Bland- Altman.Results:1 AS curve and bull ’s-eye map features of coronary stenosis group and without coronary stenosis groupAS curve of without coronary stenosis group was negtive single-peak, smooth, shape was consistent,red bull ’s-eye map was relatively uniform;AS curve of coronary stenosis group was disorder,twisted,negative single-peak disappeared, or even reversed,red bull ’s-eye map unevenly distributed,corresponding parts of some myocardial segments turned light or blue.2 The comparison of general parameters and GAS between coronary stenosis group and without coronary stenosis groupGAS in coronary stenosis group significantly reduced compared with without coronary stenosis group(P<0.05),EDV,ESV,LVEF,etc,had no difference between the two group relatively(P>0.05).3 The comparison of AS among different degrees of coronary stenosis myocardial segmentsSegmental AS gradually reduced with the increasing of the degree of coronary stenosis.There was no statistically difference of segmental AS among without coronary artery group normal myocardial segments,coronary stenosis group normal myocardial segments and mild coronary stenosis myocardial segments(P>0.05),AS in moderate and severe coronary stenosis myocardial segments significantly reduced by comparison(P<0.05),and that in severe coronary stenosis myocardial segments was lower than that in moderate coronary stenosis myocardial segments, the differences were statistically significant(P<0.05).4 Left ventricular GAS of all objects was significantly correlated with coronary artery Gensini score(r=0.828,P<0.01) by Pearson correlation analysis.5 Variation coefficients of RT3D-STI GAS were 3.53% for intraobserver and 5.04% for interobserver with good consistency.Conclusions:GAS and myocardial segmental AS of RT3D-STI can quantitatively assess the early changes of left ventricular globle and regional myocardial systolic function in coronary stenosis patients without RWMA,showing high reliability and providing reliable clinical basis for early detection of coronary stenosis patients.