Applied Study Of Evaluation On Ventricular Synchrony And Cardiac Function In Patients With Cardiac Resynchronization Therapy By Two-dimensional Speckle Tracking Imaging And Real-time Three-dimensional Echocardiography

Background:At present,chronic congestive heart failure(CHF)not only has high morbidity,but also has high mortality.However,there is no better treatment for CHF.Cardiac resynchronization therapy(CRT)can improve symptoms in some patients with CHF and reduce their mortality.Two-dimensional speckle tracking imaging(2D-STI)is a newly developed echocardiography with high accuracy in quantitative evaluation of cardiac function and wall motion.Real-time three-dimensional echocardiography is a major breakthrough in the field of echocardiography,with high sensitivity,specificity and good reproducibility.It can collect and acquire the heart stereo image in real time,and accurately measure the overall and local ventricular volumes.Objective:To investigate the value of 2D-STI combined with RT-3DE in evaluation of ventricular synchrony and cardiac function in patients with CRT.Methods:A total of 48 CHF patients who were eligible with Class I indications referred for CRT in this study.In addition to conventional echocardiography,2D-STI and RT-3DE were used to measure the below parameters before and 6 months after implantation:left atrial diameter(LA),left ventricular end-diastolic diameter(LVEDD),left ventricular end-systolic diameter(LVESD),left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV),left ventricular ejection fraction(LVEF),area of mitral value regurgitation(MRA),left ventricular filling time and cardiac cycle ratio(LVFT/RR),time difference between aorta and pulmonary artery ejection(IVMD),left ventricular global longitudinal strain(GLS),left ventricular global circumferential strain(GCS),left ventricular global radial strain(GRS),standard deviation of left ventricular systolic 16 segments longitudinal strain(Tls16-SD),standard deviation of left ventricular systolic 16 segments circumferential strain(Tcs16-SD),standard deviation of left ventricular systolic 16 segments radial strain(Trs16-SD),three-dimensional left ventricular end-systolic volume(3D-LVESV),three-dimensional left ventricular end-diastolic volume(3D-LVEDV),three-dimensional left ventricular ejection fraction(3D-LVEF),three-dimensional systolic dyssynchrony index(SDI),the maximal difference of time to minimal systolic volume of 16 segments and cardiac cycle ratio(Tmsv16-Dif%).We compared the differences of these parameters between responders and no-responders before and 6 months after implantation.The univariate and multivariate regression analysises were used to find the synchronic parameters related to the curative effects of CRT.The ROC curves were drawn to compare the accuracy of different parameters in predicting the response of CRT.Results:1.Evaluation of ventricular synchrony and cardiac function by 2D-STI in patients with CRT(1)Compared with the echo parameters before implantation,they were improved significantly 6 months after implantation measured by 2D-STI.The differences were statistically significant(P<0.05).(2)In a total of 48 CRT patients,35 of them were responders,13 were non-responders.Compared with the echo parameters before implantation between responders and non-responders,we found that the response in non-ischemia cardiomyopathy(NICM)patients was significantly better than that in ischemia cardiomyopathy(ICM)patients.Both GLS and Tls16-SD had significantly differences in responders and non-responders(P<0.05).(3)LVEDD and LVEDV measured before implantation were larger in NICM patients than those in ICM patients,and other parameters were no differences in NICM and ICM patients(P>0.05).2.Evaluation of ventricular synchrony and cardiac function by RT-3DE in patients with CRT(1)Compared with the echo parameters before implantation,3D-LVESV and 3D-LVEDV decreased,3D-LVEF increased,3D-SDI and Tmsv16-Dif%were also improved.The differences were all statistically significant(P<0.05).(2)Compared with the echo parameters before implantation between responders and non-responders,SDI and Tmsv16-Dif%had significantly differences(P<0.05),while there were no differences in 3D-LVEF,3D-LVESV and 3D-LVEDV(P>0.05).3.Prediction of response to patients with CRT by 2D-STI and RT-3DE(1)Compared with the echo parameters before implantation in responders and non-responders,GLS,Tls16-SD%,SDI and Tmsv16-Dif%had significantly differences(P<0.05).The response in NICM patients was significantly higher in ICM patients.(2)Using univariate analysis of clinic and echo-related parameters with CRT response(6 months after implantation),it was found that NICM,GLS,Tls16-SD,SDI and Tmsv16-Dif%had significant correlation with response of CRT(P<0.05).Then using multivariate regression analysis,it was revealed that only GLS and SDI were significantly associated with the response of CRT(P<0.05).ROC curves of GLS,SDI and GLS combined with SDI were Separately drawn,and the largest area under curve was 0.908,with sensitivity 91.4%,specificity 84.6%,which belonged to GLS combined with SDI(P<0.05).Conclusions:CRT can significantly improve ventricular synchrony and cardiac function in CHF patients with indications of CRT implantation,but there are still some non-responders after implantation.Both 2D-STI and RT-3DE can evaluate ventricular synchrony and cardiac function of CRT patients accurately and quantitatively.The combination of GLS and SDI is the best method in the assessment of ventricular dyssynchrony and can use it for screening and evaluation of CRT patient evaluation prior to and after CRT procedures.