Evaluation on changes of left atrial function after coronary artery bypass grafting using two-dimensional speckle tracking imaging and real-time three-dimensional echocardiography / 中国医学影像技术

ABSTRACT

Objective To evaluate changes of left atrial function after coronary artery bypass grafting (CABG) with two-dimensional speckle tracking imaging (2D-STI) and real-time three-dimensional echocardiography (RT-3DE). Methods Totally 30 patients with multivessel coronary artery disease treated with CABG (CABG group) and 30 healthy volunteers (control group) were enrolled. 2D-STI was used to measure the left atrial strain curve, i.e. left atrial reserve strain (εs), conduit strain (εe) and contraction strain (εa) in control group and CABG group before operation, as well as 1 month and 3 months after operation. RT-3DE was used to measure maximum left atrium volume (LAVmax), minimum left atrial volume (LAVmin), pre-systolic left atrial volume (LAVP), left atrial passive ejection fraction (LAPEF) and active ejection fraction (LAAEF). Correlation analysis was performed between the ratio of left atrial strain, volume change and difference value of peak mitral flow velocity (E)/mitral annular peak velocity (e') 3 months after CABG and pre-operation (ΔE/e'). Results εa and LAAEF showed no significant difference among CABG group before operation, 1 month, 3 months after operation and the control group (both P>0.05), whereas εs, εe, LAVmax, LAVmin, LAVp and LAPEF were statistically significant (all P<0.05). Compared with control group, before CABG, εs, εe and LAPEF decreased, LAVmax, LAVmin and LAVp increased (all P<0.05), while compared with those before operation, εs, εe and LAPEF increased, LAVmax, LAVmin and LAVp decreased 1 month and 3 months after operation (all P<0.05), the differences of εs, εe, LAVmax, LAVmin, LAVp and LAPEF were statistically significant between 3 months and 1 month after operation (all P<0.05). The rate of changes of LAVmax, LAVmin, LAVp in CABG group 3 months after operation was positively correlated with ΔE/e'(r=0.608, 0.631, 0.587, all P<0.01), while of left atrium εs, εe was negatively correlated with ΔE/e' (r=-0.615, -0.637, all P<0.01). Conclusion 2D-STI and RT-3DE can dynamically evaluate the left atrium function before and after CABG, and have certain value in evaluating the improvement of myocardial function and prognosis after CABG.