Quantitative Assessment Of Left Ventricular Wall Motion By Velocity Mode Of Dopper Tissue Imaging

OBJECTIVES. This study was performed to observe and measure the movement of ventricular wall in patients with myocardial infarction comparing with that of normal ventricular wall and to evaluate the diagnostic value of Doppler tissue imaging(DTI) for detection of myocardium in myocardial infarction comparing with that of two-dimensional(2D) echocardiography.METHODS. The left ventricular wall motion of 46 patients with myocardial infarction(anterior-septum group in 29, inferior-posterior group in 17) and 48 HEALTH was assessed. In six views(ap4cv,ap2cv,alax,pslax,pssax(CT), pssax(PM)), The regional left ventricular wall motion was observed by 2D echocardiography according to 16 segments and abnormal movement was recorded. The thickness of myocardial segments was measured in alax. Having switched to DTI in each view, the color coded by DTI of ventricular wall motion and the form of spectrum curve of ventricular wall motion in myocardial infarction were observed and compared with those of normal myocardium. The markers(Sm, Em, PVGS, PVGe, MVGS, MVGe) of pulsed wave-DTI(PW-DTI) of segments were measured or calculated and each of them was compared in infra-group and intra-group. The diagnostic result of PW-DTI for detection of myocardium in myocardial infarction and myocardium in myocardial ischemia was compared with that of 2D echocardiography.RESULTS. 1. ㏕he color coded by DTI of ventricular wall motion was well-distributed and bright in HEALTH and endocardial velocities of the same ventricular wall which were in the same direction decreased gradually along cardiac base to cardiac apex. (2) At myocardium in myocardial infarction, the color coded by DTI of ventricular wall motionwas faint relatively and the amplitude of S wave was lower and the form of S wave was chaotic. 2. ㊣n the same direction, myocardial velocity of interventricular septum , anterior wall, anteroseptal wall was respectively smaller than that of lateral wall, inferior wall, posterior wall and endocardial velocity was larger than epicardial velocity. All above-mentioned differences were extremely significant(p<0.01 or p<0.05). (2) No matter long-axis or short-axis, all velocities of segments in patients with myocardial infarction were smaller than those in HEALTH and the majority of differences was significant(p<0.01 or p<0.05).However, there were differences of velocity variety existed between ventricular wall in myocardial infarction and normal ventricular wall. In the direction of long-axis, the velocity difference between anteroseptal endocardium and anteroseptal epicardium was not significant(p>0.05) in patients with anterior-septum myocardial infarction and the velocity difference between posterior endocardium and posterior epicardium was still significant(p<0.05) and larger significantly than that of HEALTH(p<0.05). In patients with inferior-posterior myocardial infarction, the decreasing degree of velocity in inferior wall(long-axis) and in posterior wall(short-axis) was respectively more significant than that in anterior wall and in anteroseptal wall(p<0.01 or p<0.05). 3. Except for cardiac apex, the positive rate of PW-DTI for detection of segments whose ventricular wall motion was abnormal was larger than or equal to that of 2D echocardiography. The accuracy and sensibility of PW-DTI for detection of myocardium in myocardial infarction and myocardium in myocardial ischemia were all larger than those of 2D echocardiography and the specificity of PW-DTI for detection of myocardium in myocardial infarction and myocardium in myocardial ischemia was smaller than that of 2D echocardiography. The difference of sensibility and of specificity was respectively significant between PW-DTI and 2Dechocardiography(p<0.05). 4. The repetition of PW-DTI for detection of myocardial velocity was better among infra-examiner and within intra-examiner.CONCLUSIONS. 1. DTI is a new technigue by which operation is simple and non-invasive and by which detection is accurate > quantitative and easy to repeat. 2. The feature of normal...