Assessment Of Left Ventricular Myocardial Strain In Patients With Different Degrees Of Coronary Artery Stenosis By Speckle Tracking Imaging

BackgroundCoronary artery stenosis can reduce myocardial blood supply and lead to segmental dysfunction of the myocardium at the corresponding segments of the ventricular wall,which is the basis for ultrasound diagnosis of coronary heart disease.It is of great clinical significance to find a simple,quantitative and safe method to evaluate coronary artery stenosis.Echocardiography is commonly used to evaluate the segmental dysfunction of the ventricular wall.Speckle tracking imaging can quantitatively evaluate the local and global function of the heart by tracking the movement track of the spots in the myocardium and measuring the myocardial strain parameters during the movement.And the results of this method are reliable.Automated Functional Imaging(AFI)and Real-Time Three-Dimensional Speckle Tracking Imaging(RT3D-STI)are the latest development and improvement of speckle tracking imaging technology.ObjectiveAFI and RT3D-STI are used to evaluate the changes of local and global strain parameters of left ventricular myocardium in patients with different degrees of coronary stenosis without segmental wall motion pulsation,and to explore the values of various parameters and speckle tracking imaging in the determination of coronary artery stenosis.MethodsFrom March 2018 to July 2018,100 patients with coronary heart disease who underwent coronary angiography are selected from the Department of Cardiology,First Affiliated Hospital of Zhengzhou University.According to the stenosis degree of coronary angiography,the patients are divided into four groups: non-stenosis group(0%),mild stenosis group(1%-49%),moderate stenosis group(50%-75%)and severe stenosis group(>75%).Cardiac color Doppler examination is performed before angiography,and 17 segment strain bovine eye maps of left ventricular wall are obtained by AFI and RT3D-STI.The global peak longitudinal strain(2D-GLPS)of left ventricle and the local peak longitudinal strain(2D-LLPS)of corresponding segments of each coronary artery branch are obtained by AFI.The left ventricular global longitudinal strain(4D-GLPS),global circumferential strain(4D-GCPS),global area strain(4D-GAPS),global radial strain(4D-GRPS)and the corresponding segments of the coronary branch local longitudinal strain(4D-LLPS),local circumferential strain(4D-LCPS),local area strain(4D-LAPS),local radial strain(4D-LRPS)are obtained by RT3D-STI.Results1.The angiographic results show that there are 12 patients without coronary artery stenosis,24 patients with single coronary artery stenosis(21 patients with anterior descending artery stenosis,2 patients with circumflex artery stenosis,1 patient with right coronary artery stenosis),22 patients with double coronary artery stenosis(12 patients with anterior descending artery and circumflex artery stenosis,10 patients with anterior descending artery and right coronary artery stenosis),and 42 patients with three coronary artery stenosis.2.There is no significant difference in gender,age,incidence of hypertension,diabetes mellitus and hyperlipidemia,heart rate,PRO-BNP serum level,LVEDV and LVESV among the four groups with different degrees of coronary artery stenosis(P > 0.05),but LVEF in severe stenosis group is significantly lower than that in non-stenosis group,mild stenosis group and moderate stenosis group(P < 0.05).3.As a whole: the overall strain parameters have a tendency to decrease as the degree of stenosis increases.There are significant differences in 2D-GLPS,4D-GLPS,4D-GCPS and 4D-GRPS between non-stenosis group and moderate stenosis group(P < 0.05),and significant differences in 2D-GLPS,4D-GLPS,4D-GCPS,4D-GAPS and 4D-GRPS between non-stenosis group and severe stenosis group(P < 0.05).There are significant differences between mild stenosis group and moderate stenosis group in 2D-GLPS,4D-GLPS and 4D-GRPS(P<0.05),and significant differences in 2D-GLPS,4D-GLPS,4D-GCPS,4D-GAPS and 4D-GRPS between mild stenosis group and severe stenosis group(P<0.05).There is no significant difference between non-stenosis group and moderate stenosis group,and between moderate stenosis group and severe stenosis group(P > 0.05).4.For the local part: the strain parameters of each branch have a tendency to decrease as the degree of stenosis increases.In the anterior descending branch,there are significant differences in 2D-LLPS,4D-LLPS,4D-LCPS,4D-LAPS and 4D-LRPS between non-stenosis group and moderate stenosis group,the severe stenosis group(P < 0.05),and significant differences in 2D-LLPS,4D-LLPS,4D-LAPS and 4D-LRPS between mild stenosis group and moderate stenosis group(P < 0.05).There are significant differences in 2D-LLPS,4D-LLPS,4D-LCPS,4D-LAPS and 4D-LRPS between mild stenosis group and severe stenosis group(P < 0.05).There is no significant difference between non-stenosis group and mild stenosis group,and between moderate stenosis group and severe stenosis group(P > 0.05).In the circumflex branch,there are significant differences in 2D-LLPS between non-stenosis group and moderate stenosis group(P < 0.05),and significant differences in 2D-LLPS,4D-LLPS,4D-LCPS,4D-LAPS and 4D-LRPS between non-stenosis group the severe stenosis group(P < 0.05).There are significant differences in 2D-LLPS between mild stenosis group and moderate stenosis group(P < 0.05),and significant differences in 2D-LLPS,4D-LLPS,4D-LCPS,4D-LAPS and 4D-LRPS between mild stenosis group the severe stenosis group(P < 0.05).There is no significant difference between non-stenosis group and mild stenosis group,and between moderate stenosis group and severe stenosis group(P > 0.05).In right coronary artery,there is no significant difference between the groups.5.ROC curve shows that in the overall diagnosis,the area under the curve of 2D-GLPS is the largest,and AUC(95% CI)is 0.823(0.738-0.907),the cutoff value is-20.25 with 86.5% sensitivity and 74.6% specificity.In the diagnosis of anterior descending branch,the area under the curve of 4D-LRPS is the largest,AUC(95% CI)was 0.772(0.679-0.865),the cutoff value is 42.50 with 84.1% sensitivity and 69.6% specificity.In the diagnosis of the circumflex branch,the area under the curve of 2D-LLPS is the largest,AUC(95% CI)is 0.775(0.678-0.873),the cutoff value is-18.10 with 60.0% sensitivity and 86.7% specificity.In the diagnosis of right coronary artery,the area under curve of 4D-LLPS is the largest,AUC(95% CI)is 0.660(0.550-0.770),the cutoff value is-15.50 with 54.5% sensitivity and 82.4% specificity.6.LVEF is negatively correlated with left ventricular strain parameters including 2D-GLPS,4D-GLPS,4D-GAPS and 4D-GCPS(P < 0.001),positively correlated with strain parameters including 4D-GRPS(P < 0.001).And 4D-GAPS has the strongest correlation with LVEF.ConclusionSpeckle tracking imaging AFI and RT3D-STI can reflect the changes of strain parameters of myocardium corresponding to coronary artery stenosis,and it can evaluate the degree of coronary artery stenosis in patients with coronary heart disease who have abnormal wall motion abnormalities to some extent.The combination of AFI and RT3D-STI is more effective.