Evaluation of the effect of coronary artery bypass grafting on left atrial function with strain rate imaging / 中华超声影像学杂志

ABSTRACT

Objective To explore the effect of coronary artery bypass grafting(CABG) on left atrial (LA) function by strain rate imaging(SRI). Methods Twenty-three patients with coronary heart disease who underwent coronary artery bypass grafting were involved. SRI was performed on those patients to evaluate LA function quantitatively at baseline (before CABG),and at 1 week, 1 month and 3 months after CABG. Peak strain rate(SR) was measured at each segment (septal, lateral, posterior, anterior, and inferior walls) and mean peak systolic SR (SRs),peak early diastolic SR (SRe) and peak atrial systolic SR (SRa) were calculated by averaging data in each segment. Results Compared with the baseline,LV pre-systolic volume(LAVp), maximal volume (LAVmax), minimal volume (LAVmin), LV active emptying fraction (LAAEF) and passive empting fraction(LAPEF) had on significant differences at 1 week (P >0.05). LAVp,LAVmin,LAVmax and LAAEF decreased gradually after CABG, LAPEF increased gradually after CABG (P <0.05). Compared with the baseline, the peaks of SR curve showed no significant differences at 1 week (P >0.05). Nevertheless,the peaks of SR were increased at systole and early diastole,decreased at atrial contraction at 1 month (P <0.05). Those changes were turned more significantly at 3 months (P 0.01). Left ventricular ejection fraction (LVEF) both increased at 1 month and 3 months,and its changing rate correlated inversely with the changing rate of SRa respectively (r = -0.751, -0.783,all P<0.01).Conclusions LA function is affected by CABG, presented as reservoir and pump functions decreased and conduit function increased. SRI can evaluate the atrial function quantitatively and monitor the changing of LA function dynamically after CABG.