应变率成像评价冠状动脉搭桥对冠心病患者左心房功能的影响

目的 应用应变率成像(SRI)技术评价冠状动脉搭桥(CABG)对冠心病患者左心房功能的影响.方法 分别于CABG术前、术后1周、1月和3月应用SRI技术对23例冠心病患者左心房功能进行评价.结果 与术前比较,术后I周左心房收缩期前容积(LAVp)、最大容积(LAVmax)、最小容积(LAVmin)、主动排空分数(LAAEF)及被动排空分数(LAPEF)变化差异无统计学意义(P>0.05);术后1月,LAVp、LAVmax、LAVmin和LAAEF减小,LAPEF增加,差异均有统计学意义(P<0.05);术后3月,上述指标变化更为显著,差异均有统计学意义(P<0.01).与术前比较,术后1周SRs、SRe和SRa差异无统计学意义(P>0.05),术后1月SRs和SRe升高、SRa降低,差异均有统计学意义(P<0.05);术后3月SRs和SRe升高更为显著,SRa降低更明显,差异均有统计学意义(P<0.01).与术前比较,术后1月、3月左室射血分数的变化率分别与SRa的变化率呈显著负相关(r=-0.751,-0.783,均P<0.01).结论 CABG术可影响冠心病患者左心房功能,表现为储蓄功能和辅泵功能减低,管道功能增加.SRI可以评价左心房功能,动态观察CABG手术前、后左心房功能的变化.

Evaluation of the effect of coronary artery bypass grafting on left atrial function with strain rate imaging

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.