The Assessment Of Left Ventricular Twist And Untwist In Patients With Acute Infarcted Myocardial By Two-Dimensional Speckle Tracking Imaging

Objective:To assess the left ventricular twist and untwist in patients with acute infarcted myocardial (AMI) by two-dimensional speckle tracking imaging (STI),and to assess the effect of different treatment methods.Methods:100 patients with AMI are selected. Patients with AMI were divided according to 3 methods:1.Be divided into two groups according to global LV systolic function: normal LV ejection fraction (LVEF) group, (LVEF=50%, n=46) and abnormal LVEF gruop (LVEF<50%, n=36).2. Be divided into three groups according to different parts of myocardial infarction:anterior myocardial infarction group, (n=30),inferior myoctardia infarction group(n= 30) and partition myoctardia infarction group(n=30).3. Be divided into three groups according to different treatment methods:emergeney percutancous coronary intervention group(n=30),selecting time percutancous coronary intervention group(n=25) and expectant treatment group(n=25),and giving them a following up after discharge from hospital 4 to 6 months.40 healthy subjects are selected simultaneous to be the control group.GE Vivid 7 ultrasound diagnostic applications,the conventional two-dimensional echocardiography, conventional measurement data including the Left Ventricular diastollc diameter (LVDd),Left Ventricular systolic diame(?)(LVDs),Left Ventricular Ejection fraction(LVEF) and E/A,and rotation were measured in the left ventricular short-axis views using 2D-strain software. LV Peak twist(Ptw),apical Peak rotation (PAR), the basal Peak rotation (PBR) and the time to Peak were measured separately, twist at aortic valve closure(AVCtw), twist at mitral valve opening (MVO tw), untwisting rate(Untw R), and half time of untwisting (HTU)were calculated.Results:1. In the control group,the rotation of apical is anticlockwise,the rotation of basal is clockwise in systole;the untwisting of apical is clockwise and the untwisting of basal is anticlockwise in diastole.The rotation of left ventricular is anticlockwise. In AMI group,the rotation trend of the apical and basal is identical compared with the control group. The rotation of left ventricular is anticlockwise too. The value of Ptw and PAR significantly decreased in AMI group.2. Be divided according to global LV systolic function:Compared with the control group, the value of Ptw,PAR,PBR,AVCtw and MVOtw significantly decreased in abnormal LVEF group, and in normal LVEF group,the value of Ptw,PAR,AVCtw and MVOtw decreased Compared with the control group. Compared with normal LVEF group,the value of Ptw,AVCtw and MVOtw significantly decreased in abnormal LVEF group.3. Be divided according to different parts of myocardial infarction:Compared with the control group, the value of Ptw, PAR, AVCtw and MVOtw significantly decreased in myocardial infarction group; the value of PAR decreased in anterior wall myoctardia group compared with another two group.4. Be divided according to therapeutic method:Compared with the expectant treatment group, the value of Ptw, PAR in the following up are improved in emergeney percutancous coronary intervention group and selecting time percutancous coronary intervention group, the value of LVEF improved are no significant difference.5. The correlation was found between LV twist and LVEF.,r=0.527,p<0.05;No correlation was found between UntwR and E/A,p>0.05.Conclusions:1.Left ventricular twist trend isn't change in AMI patients, but the value of Ptw and PAR significantly decreased, indicating that myocardial infarction can damage regional systolic function and distortion ability. and untwist can be measured using speckle tracking echocardiography. LV rotation can be the quantitative index to evaluate the systolic function of LV.2.Ptw is significantly correlated with LVEF,and when Ptw was decreased LVEF was not decreased,indicating that Ptw can assess LV systolic function more exactly than LVEF.3. The effect of apical rotation was more significant in anterior wall myoctardia group than inferior myoctardia infarction group and partition myoctardia infarction group.The apical was very important in LV rotation. 4. After emergeney PCI and selecting time PCI, the left ventricular rotation and apical rotation angle were more inproved than expectant treatment,the relieving of infarction related artery is the best treatment for AMI.5. The time to Peak of LV rotation and the parameter of untwisting aren't chaged in AMI,needing enlargement the sample for more research.