Study On Evaluation Of The Coronary Artery By Examining Ventricular Wall Motion With Real-time Three Dimensional Echocardiography

Objective:Detecting the left ventricular regional wall motion abnormality (RWMA) with real-time three-dimensional echocardiography (RT-3DE), explore the relationship of the RWMA and coronary artery stenosis and evaluate the degree of coronary artery stenosis.Methods:One hundred and fifty hospitaized patients (male96cases, female54cases, mean age63.4±13.6years) with suspected CHD were enrolled in the research, They were to undergo coronary angiography (CAG). Three groups were divided into group A (left anterior descending artery lesion group), group B (left circumflex artery lesion group) and group C (right coronary artery lesion group). In the each group, subgroups were further divided into group A1/B1/C1and group A2/B2/C2according to whether the stenosis of coronary artery was≥75%or≤75%. Sixty eight patients who were no significant stenosis of coronary artery showed by CAG were enrolled as a control group. All patients underwent routine echocardiography and their left ventricular ejection fraction (LVEF) were>50%. RT-3DE examination was performed and the required section was recorded, Using RT-3DE of QLAB3DQ advanced quantitative analysis software program to get17segments VTC and bull’s-eye diagram, sequence frame by frame analysis, recording an average LV16segments range of motion EA; systolic ventricular peak exercise time (TS); segmental diastolic end volume (sEDV), segmental systolic volume (sESV), calculated the formula segmental left ventricular ejection fraction (sEF), sEF=(sEDV-sESV)/sEDV*100%. Some parameters on the resulting ROC curve were analysised. The area under the curve and the index cutoff value were recorded. All datas were statistically analyzed and processed. The discriminant analysis was performed.Results:1. The EA of middle section and apical segment of anterior and anterior septum wall in group A2wes significantly lower than that in group Al or group N (p<0.05), the sEF of middle segment of anterior wall and apical segment of anterior and anterior septum wall in group A2wes significantly lower than that in group Al or group N (p<0.05), there was no significant difference between group Al and group N. There was no significant difference of Ts among the three groups (p>0.05).2. The EA of basal and middle segment of lateral wall, basal segment of posterior wall in group B2wes significantly lower than that in group B1or group N (p<0.05), the sEF of basal and middle segment of lateral wall and basal segment of posterior wall in group B2wes significantly lower than that in group B1or group N (p<0.05), there was no significant difference between group B1and group N. There was no significant difference of Ts among the three groups (p>0.05).3. The EA of basal and middle segment of inferior wall and posterior septum wall,basal segment of posterior wall in group C2wes significantly lower than that in group C1or group N (p<0.05), the sEF of basal segment of inferior wall and posterior septum wall in group C2wes significantly lower than that in group C1or group N (p<0.05), there was no significant difference between group C1and group N. There was no significant difference of Ts among the three groups (p>0.05).4. The VTC are "U-shaped" and uniform and the coordinates of curve peak and valley are nearby in patients in group N, patients of the group VTC was irregular and clutter, normal segmental amplitude is larger, ischemic segments amplitude is small or even reverse movement in patients in group A2/B2/C2. The patients in group A1/B1/C1had a similar VTC but shape was irregular. The bull’s-eye map was displaying all left ventricular segmental are green in the patients in group N,but the bull’s-eye map showed red in the part of the left ventricular segments in group A2/B2/C2..5. The area under the ROC of sEF of apical and middle segment in anterior wall, middle segment in anterior septum wall were89.4%,87.7%,95.3%, their intercept values were53.57%,50.84%,53.14%respectively in group A. The area under the ROC of EA of apical and middle segment in anterior wall and anterior septum wall were92,8%,91.5%,94.5%,90.3%,their cutoff value were5.67,5.31,5.39,5.25respectively in group A;6. The area under the ROC of sEF of basal and middle segment in latearl wall were91.8%,89.3%, their intercept values were51.17%,52.79%respectively in group B; The area under the ROC of EA of basal and middle segment in anterior wall and basal segment in posterior wall were94.1%,94.6%,92.7%, their cutoff value were5.48,5.31,4.88respectively in group B.7. The area under the ROC of sEF of basal segment in inferior wall and posterior septum wall were91.5%,88.9%, their intercept values were48.77%,50.96%respec- tively in group C; The area under the ROC of EA of basal and middle segment in inferior wall and basal segment in posterior wall were93.2%,89.4%,94.5%, their cutoff value were4.63,5.25,4.88respectively in group C.8. The stenosis≥75%as the grouping variable, group A1/B1/C1was defined1, group A2/B2/C2was defined2, the EA and sEF as independent variables, the discriminant function was Y=0.461sEF+0.672EA(group A); Y=0.500sEF+0.771EA1+0.783EA(group B); Y=0.830sEF+0.481EA(group C) respectively. The critical value of discriminant was Ya=0.438, Yb=0.694, Yc=0.653respectively; The correct rate of the discriminant function and the critical value was over85%; The sensitivity and specificity of stenosis coronary (≥75%) were82%-92%.Conclusion:1. The EA, sEF in the segments which was supplied by stenosis coronary artery (≥75%) reduced significantly, there was no significant change in Ts. It suggested that exercise and capacity parameter are more sensitive then time parameter for judging the degree of coronary stenosis.2.The VTC and the bull’s-eye diagram can recognize the segments supplied by stenosis coronaries and the lesion site of coronary.3. The area under the ROC and the cutoff value of EAand sEF in part myocardial segments may be as one of indicators by which stenosis coronary(≥75%) was corresponded.4. The correct rate of the discriminant function and the critical value was over85%. Their sensitivity and specificity were82%-92%for diagnosis of stenosis coronary (≥75%).5. The conclusion need to be confirmed by further studies because the sample size was smaller in our study.