The Evaluation Of Tissue Velocity Imaging On The Left Ventricular Regional Contractive Function In Coronary Artery Disease

Objectives To evaluation diagnosis value on ischemic myocardium in patients with coronary artery disease(CAD) by tissue velocity imaging(TVI) including quantitative tissue velocity imaging(QTVI),tissue tracking imaging(TZI),strain imaging(SI)and strain rate imaging(SRI),compare the difference of the four techniques in evaluating ischemic myocardium in CAD;to evaluation left ventricular regional contractive function quantitatively before and after percutaneous coronary intervention(PCI),and determine the therapeuric efficacy of PCI in patients with CAD.Methods(1)From April 2007 to November 2007,72 patients(50 men,22 women;mean age(56.97±10.78) years)with CAD according to the results of coronary arteriography(CAG)in SXMU First Hospital were enrolled in this study,which were divided into two groups,one of which was myocardial infraction group(n=17) and the other one was non- myocardial infraction group(n=55).Then,according to the degree of blood-supply coronary artery stenosis,55 patients were divided into group 1,2,3(coronary artery stenosis＜50%,50%-75%,＞75%,respectively).And there was no other heart disease in all the objects.In 15 patients with CAD transthoracic echocardiographic views at the apical level were obtained before and after PCI.(2)Vivid 7 color Doppler ultrasound diagnostic instrument was used and an M3S transducer in harmonic 1.7-3.4 MHz mode was adopted,frame frenquency of which was above 90 frames/s.The TVI images from long axis view of left ventricle,apical two-chamber view,apical four-chamber view and apical long axis view of left ventricle in 3 continuous cardiac cycles were recorded.(3)The post septum,lateral wall,anterior wall and inferior wall were divided into 16 segments by the method of American echocardiogram academy,and increased 2 segmengts to 18 segments.(4)The velocity-time curve of QTVI,displacement-time curve of TTI,strain curve of SI and strain rate curveof SRI were acquired in different segments under the modes of QTVI,TTI,SI and SRI,respectively,according to which,SV,SD,S and SR were measured.Results1.SV,SD,S,SRI were lower significantly in myocardium with coronary stenosis,until myocardial infraction group(P＜0.05).1)The change of SD and SV,(base segments and middle segments and anterior wall apical segment of theleft anterior descending branch)SV,SD were lower significantly between myocardial infraction group and grade 1,grade 2(P＜0.05);(apical segments of posterior wall,anterior wall,posterior septum and inferior wall) SD were lower significantly between myocardial infraction group and grade 1(P＜0.05);(anterior septum base segment,anterior wall base segment and middle segment) SV,SD were lower significantly between grade 3and grade 1(P＜0.05);There was no significant difference between myocardial infraction group and grade 3(P＞0.05).2) The change of S and SR,all 11 segments S,SR were lower significantly between myocardial infraction group and grade 1(P＜0.05);(except apical segment of siderior wall) 10 segments S,SR were lower significantly between myocardial infraction group and grade 2(P＜0.05);5 segments(anterior septum base segment and middle segment,anterior base segment and middle segment and apical segment) S,SR were lower significantly between myocardial infraction group and grade 3(P＜0.05);5 segments(anterior septum base segment and middle segment,anterior wall base segment and middle segment and apical segment) S,SR were lower significantly between grade 3 and grade 1(P＜0.05).2.In 15 patients with CAD transthoracic echocardiographic views at the apical level were obtained before and 1 week,1month and 3 month after PCI,SV,SD,S,SRI were higher significantly.1) The change of SD and SV before,after PCI,since 1 month after PCI,2 segments (anterior wall base segment and middle segment)SV and SD were higher significantly than of before PCI(P＜0.01);after 3 months,8 segments(except apical segment of anterior septum,siderior wall,posterior septum) SV and SD were higher significantly than of before PCI(P＜0.01);6 segments(anterior septum base segment and middle segment,anterior wall base segment and middle segment,posterior septum base segment and posterior wall apical segment) SV and SD were higher significantly than of 1 week after PCI(P＜0.01).2) The change of S and SR before,after PCI,since 1 week after PCI,3 segments(anterior wall base segment,middle segment and apical segment)S and SR were higher significantly than of before PCI(P＜0.01);after 1 months,5 segments(anterior septum base segment and middle segment,anterior wall base segment and middle segment and apical segment) S and SR were higher significantly than of before PCI(P＜0.01);3 months after PCI,9 segments(apical segment of except siderior wall and posterior septum wall) S and SR were higher significantly than of before PCI,1 week after PCI(P＜0.01).Conclusions1.With the aggravation of coronary stenosis,the contractive peak of QTVI,TTI,SI and SRI of the corresponding segments decreased gradually—regular variation.2.Tissue velocity imaging could evaluate the regional myocardial function of ischemic myocardium quantitatively and determine the therapeutic efficacy of PCI in patients with CAD.