The Value Of Quantitative Tissue Velocity Imaging In Studying The Motion Of Ventricular Wall And Myocardial Synchronicity On Patients With Coronary Artery Diseases

Background:Tissue Doppler Imaging(TDI) is a promising technology of echocardiography. It can evaluate regional myocardial motion along the long axis and offer more quantitative information about myocardial wall velocities and time durations in real-time. Quantitative Tissue Velocity Imaging(QTVI) is one modality of TDI. QTVI allows assessment of myocardial velocities of eight segments at the same two-dimensional echocardiography image.QTVI also offers more detailed information of velocities and time changes.There are many relevant researches to assess the velocities of segmental movement and cardiac synchronicity. But the features during isovolumic contraction ,the myocardial synchronicity and the relationship between +IVC and recovery of regional contraction are still not clear.Objective:The aim of this study was to evaluate changes that occur in IVC myocardial velocities in subjects who underwent angina or AMI, to investigate a sensitive index which can best predict the impairment of coronary artery,at the same time to explore the myocardial synchronicity and the relationship between +IVC and recovery of regional contraction.Methods:Group A consisted of forty-eight normal subjects, and group B included forty-two patients with angina. Thirty-two patients with AMI and an occluded left anterior descending artery were selected in group C, and thirty-four patients with AMI and heart failure were selected in group D. The patients of group C at one-month follow-up were selected in group E. From the apical four-chamber view, two-chamber view and the apical long-axis view, longitudinal myocardial velocities were assessed in twelve predefined myocardial segments. Peak velocities during IVC(peak positive and where visible, peak negative and differential) were measured in all groups. The time interval from the onset of QRS wave of the EKG to the peak systolic velocity(Ts) and the peak diastolic velocity(Te) were measured in group D.Results:Among A,B,C groups, the sex, age and heart rate showed no significant differences. The -IVC was similar. But +IVC was significantly different.Between A and B groups,the main parameters of routine echocardiography showed no significant differences. But the percentage of segments with negativeâ–³IVC was significantly different. When +IVC was used to evaluate the impairment of LAD, the +IVC at middle segment of anterior inter ventricular septum was best.Intraventricular contractile dyssynchrony was found in group D. In patients with recovery of regional contraction, the +IVC was obviously increased after one month of PCI than that after one week of PCI. But In patients without recovery, the +IVC was not increased.Conclusions:The +IVC is a sensitive index of echocardiography . Between patients with angina and AMI, +IVC was significantly different, which indicate +IVC may be relevant to the ischemic degree.When the percentage of segments with negativeâ–³IVC were amounted to 33.33 % or more than, it indicate that to do further diagnostic method of CAG for patients may be necessary. When +IVC was used to evaluate the impairment of LAD, the +IVC at middle segment of anterior inter ventricular septum was best. Intraventricular contractile dyssynchrony was existed in patients with early AMI. The +IVC correlated with improvement of myocardial contraction.