Clinical Application Of Three Dimensional Speckle Tracking In Diagnosis Of Coronary Artery Disease

Objective:To quantitatively evaluate left ventricular segmental and global systolic function by 3D speckle tracking echocardiography in patients of coronary artery disease. Estimate the value of 3D strain in clinical diagnosis of coronary artery disease.Methods:150 inpatients with suspected coronary artery disease were included in the study during 2010.9～2011.2. According to the selective coronary artery angiography, these patients were divided into 2 groups:CAD group (n=120) and normal group (n=30). CAD group was re-divided into 4 groups according to the distribution of affected coronary arteries. LAD group (n=46), LCX group (n=25), RCA group (n=23) and multi-vessel group (n=26). Gensini score was calculated according to CAG. Conventional echocardiography was applied in each patient and WMSI was calculated.3D speckle tracking echocardiography was applied in each patient to evaluate the segmental and global systolic function of left ventricle.Results:1. Compared with normal group, LV and LA were significantly dilated in all CAD groups (P<0.05). EF was decreased in multi-vessel group (P<0.05).2. Compared with normal group, wall motion score indexes in CAD groups were significantly increased (P<0.05).3. Compared with normal group, peak systolic 3D strain in BA, BAS, MA, MAS, MS, AA, AS, AI, AL were decreased in LAD group (P<0.05). Peak systolic 3D strains in BP, BL, MP, ML, AL were decreased in LCX group (P<0.05). Peak systolic 3D strains in BS, BI, MS, MI, AS, AI were decreased in RCA group (P<0.05). Peak systolic 3D strains in all segments were decreased in multi-vessel group (P<0.01). 4. Receiver-operating characteristic curve analysis demonstrated that a cutoff value of 23.88 in G3DS has a sensitivity of 90%, a specificity of 70% and an accuracy of 86% to detect CAD (P<0.01). The Youden index was 0.60. Compared with WMSI>1, G3DS<23.88 had a higher sensitivity and accuracy in the detection of CAD (P<0.01), but no difference was found in specificity (P>0.05).5. Global 3D strain correlated well with Gensini score in CAD patients (r=-0.76, P<0.01).6. Variations in peak systolic 3D strain between or within observers were both below 15%.Conclusions:1.3D STE may quantitatively evaluate left ventricular segmental and global systolic function. It shows good repeatability.2. The declination in global 3D strain may reflect the extent of coronary artery stenosis in CAD patients.