A Study On Left Ventricular Systolic Strain, Torsion And Untwisting In Patient With Coronary Artery Disease By Two-dimensional Speckle Tracking Imaging

Part One A study on left ventricular torsion and untwisting inpatient with coronary artery disease by two-dimensionalspeckle tracking imagingObjective: To investigate left ventricular torsion and untwisting inpatients with coronary artery disease by two-dimensional speckle trackingimaging.Methods: Thirt-eight patients who were diagnosed coronary arterydisease by Coronary Angiorgraphy (any of coronary artery stenosis＞50%)were divided into two groups: mild stenosis group (any of coronary arterystenosis＜75%, n=20), moderate or severe stenosis group (any of coronaryartery stenosis≥75%, n=18). Twenty healthy subjects were choosed as controlgroup. Recording the left ventricular short-axis views at basal and apicallevels, then using2D strain software calculated the left ventricular Peak Twist(Ptw), twist at aortic valve closure (AVCtw), twist at mitral valve opening（MVOtw）, untwisting Rate（Untw-R）, peak twist velocity（PTV）, timeto peak twist velocity（TPTV）.Rsults: Ptw, AVCtw, Untw-R showed a trend of decline, the differenceswere significant(P＜0.05). TPTV showed a trend of increasing, thedifferences were significant(P＜0.01). PTV of the moderate-severe stenosisgroup was lower than the rest of two groups,the differences weresignificant(P=0.043). Untw-R and Ptw had a negative linear correlation to leftvertricular end-systolic volume(r=-0.26、-0.36，P=0.047、0.006）. Untw-R hadpositive correlation to LVSV、LVEF、E/A, e/a and Ptw(r=0.43,0.65,0.41, 0.537,0.69，P=0.001,＜0.001,=0.001,＜0.001,＜0.001）. Untw-R had anegative linear correlation to E-wave decending time (E-DT), E/e（r=-0.325,-0.425,P=0.012）. Ptw had positive correlation to LVEF（r=0.39，P=0.002）.Conclusion: STI could evaluate left ventricular torsion correctly. Alongwith the narrow aggravating coronary artery lesions, Ptw, AVCtw, Untw-R ofthe patients with coronary artery disease became lower. Untw-R is aquantitative index to evaluate myocardial diastolic function. Part Two Assessment of Ischemia Myocardial SystolicStrain,Rotation and Torsion in Patients with Coronary ArteryDisease by Two-Dimensional Speckle Tracking ImagingObjective: To assess strain,rotation and torsion of ischemia myocardiumin patients with coronary artery disease(CAD) by two-dimensional speckletracking imaging(2D-STI), and to explore the changes of the strain,rotationand torsion in different graded coronary artery stenosis.Methods: Thirty one patients with CAD were enrolled into this studyand21healthy volenteers in the control groups(357segments).According tostenosis degree of coronary artery, the affected myocardiums were dividedinto two groups.＜70%group(137segments),≥70%group(174segments).2Dstrain software was used to calculate the radial strain(RS),circumferentialstrain(CS), longitudinal strain(LS), rotation and torsion at three levels of the shorts axis views (mitral valve,papillary muscle and cardiac apex) and apical4-chamber view, apical2-chamber view and long axis view in the samecardiac cycle.Results: Compared with control group, the RS,CS,LS,and torsion werelower in CAD group, the differences were statistical significant (LS：-21.06±2.26VS17.47±2.92、-14.91±2.91；CS：-22.29±3.50VS-19.72±6.99;-15.75±3.90；RS:24.52±9.89VS20.95±7.53、15.97±2.61,P＜0.05). With thefurther impairment of coronary artery stenosis,these values became lower.The AUC of the LS was biggest. And when the cut value was-17.58%, thesensitivity was93%, the specificity was52%.Conclusions: Systolic dysfunction of left vertricular regionalmyocardium in patients with CAD could be accurately analyzed by2D-STI.The decreased vaules of the RS，CS，LS and torsion could reflect theseverity degree of coronary artery stenosis.