Assessment Of Left Ventricular Synchrony Of The Patients With Chronic Heart Failure By Tissue Doppler Imaging And Speckle Tracking Imaging

ObjectiveWith tissue velocity imaging(TVI) and speckle-tracking imaging(STI) technique, this study compare the data of synchrony of the contraction of left ventricle(LV)myocardium between health person and patients with chronic heart failure(CHF).The purposes of this study were:To assess the LV dysynchrony above them in the long and radial axis;To compare difference between them about the LV dysynchrony in the long and radial axis.Materials and Methods1.Subjects:The study subjects include 27 healthy volunteers(15 men,12 women;range:26-64 years mean age 43±10 years) and 26 patients with CHF(17 men,9 women,range:13-76 years,mean age 50±16 years).16 patients with dilated cardiomyopathy,9 patients with ischemic cardiomyopathy(comfirmed by coronary angiography),1 patients with alcohol cardiomyopathy.All patients were excluded arhythmia.2.Echocardiography:All echocardiographic studies with Doppler studies were performed with an echocardiography system(GE VIVID7-DIMENSION).Digital routine grayscale 2-dimensional and TDI cine loops from 4 consecutive beats were obtained at end-expiratory apnea from standard apical and mid-LV short-axis views.Mean frame rates were 60±15 Hz for grayscale imaging used for specke tracking and 100 to 154 Hz for TDI.Sector width was optimized to allow for complete myocardial visualiztion while maximizing frame rate.Specific views used for this study included:mid-LV short-axis views at the papillary muscle level,apical long-axis views and 4-chamber view and 2-chamber view. Quantitative analysis was performed on all digitally stored images (EchoPAC).With the software,the sample volume was placed at the following segments:LV anteroseptal,posteroseptal,anterior,lateral,inferior and posterior segments at both basal and middle levels utilizing apical four-and two-chamber,apex views,and get the curve of all segments.For the measurement of time intervals,the start of the QRS complex was used as the reference point,from which the time to peak myocardial sustained systolic velocities(Ts) during ejection phase were measured and expressed in milliseconds.For the assessment of systolic asynchrony,the standard deviation of Ts(Ts-SD) and the maximal temporal difference of Ts(Ts-diff) of all 12 segments were calculated;then in the 2D-strain program,regions of interest were placed and enveloped totally in the LV myocardium in the short-axis views at the papillary muscle level.Similar data can be obtained as previously described.3.Statistical analysis:The data were analyzed using the SPSS software(versionl3.0,SPSS Inc.,Chicago,Illinois).Summary data were expressed as mean values±SD.Comparisons of the baseline characteristics between the groups were performed with independent-sample t test.The results are expressed as p values.A value of p≤0.05 was considered statistically significant.Results1.Compared the controls and the patients with CHF,there were significant difference in HR,QRScomplex,LVEF,and LVEDD(p＜0.05),no significant difference in age(p＞0.05).2.The asynchrony indexes(Ts-diff,Ts-SD) between the controls and the patients with CHF in the long axis and radial axis had significant difference(p＜0.05).In the patients with CHF,the Ts of free wall had obviously delay,compared the Ts of opposited wall in self.3.Compared the controls,Ts-diff and Ts-SD in the patients with CHF increased significantly(p＜0.05).Ts-SD of all segments of radial strain at the papillary muscle level increased,indicating increased discrete of curve.4.After statistical analysis for 26 patients with CHF,postior and lateral walls were main in the delayed walls measured in the long axis by TVI and in the radial axis by STI.It was observed that 8 patients were both longitudinal and radial dyssynchrony(31%),5 patients were both negative(19%),and 13 patients were either(50%).Conslusions1.Compared the controls,patients with CHF have obvious dyssynchrony in the long axis and radial axis.2.In the patients with CHF,postior and lateral walls are most delayed in the long axis and radial axis3.TVI and STI technique can assess dyssynchrony of the patients with CHF,can provide more acute and abundant information for CRT,increase specificity of detection,and improve effectness for CRT.