心肌分层应变评估二叶式主动脉瓣畸形左室收缩功能的可行性研究

Feasibility of layer-specific myocardial strain in assessing left ventricular systolic function in patients with bicuspid aortic valve

目的探讨超声心动图心肌分层应变评估二叶式主动脉瓣畸形患者亚临床心肌损害的可行性。方法选择左室射血分数(LVEF)正常的二叶式主动脉瓣畸形患者104例,根据是否伴有瓣膜功能异常分为瓣膜功能正常者44例(A组)和瓣膜功能异常者60例(B组),另选50例健康志愿者为对照组。比较各组一般资料、常规超声心动图参数及心肌分层应变参数。随机选取20例患者进行观察者内和观察者间的重复性分析。结果 B组平均年龄明显高于A组,差异有统计学意义(P<0.05);B组左室舒张末内径和升主动脉内径均较A组及对照组明显增大,差异均有统计学意义(均P<0.05)。A组全层心肌收缩期整体纵向应变峰值(LSavg)、外层心肌收缩期纵向应变峰值(LSepi)、内层心肌收缩期纵向应变峰值(LSendo)均较对照组明显减小,差异均有统计学意义(均P<0.05);B组LSavg、LSepi、中层心肌收缩期纵向应变峰值、全层心肌收缩期整体圆周应变峰值、外层心肌收缩期圆周应变峰值、中层心肌收缩期圆周应变峰值均较对照组和A组明显减小,差异均有统计学意义(均P<0.05);B组LSendo、内层心肌收缩期圆周应变峰值均较对照组明显减小,差异均有统计学意义(均P<0.05)。心肌分层应变评估左室心肌整体全层、各层心动周期纵向应变峰值及圆周应变峰值观察者内部和观察者间一致性限度为-6.0%~5.0%,组内相关系数均≥0.80。结论应用超声心动图心肌分层应变评估LVEF正常的二叶式主动脉瓣畸形左室外层及内层纵向应变峰值,有利于早期检出亚临床心肌损害。

Objective To investigate the feasibility of layer-specific myocardial strain based on echocardiography in evaluating subclinical myocardial injury in patients with bicuspid aortic valve.Methods One hundred and four patients with bicuspid aortic valve and normal LVEF were selected,they were divided into normal valve function group with 44 patients(group A) and abnormal valve function group with 60 patients(group B) according to whether valve dysfunction occurred.In addition,50 healthy volunteers were selected as control group.The general clinical data,conventional ultrasound parameters and layer-specific myocardial strain parameters were compared.Twenty patients were randomly selected to analyze inter-and intraobserver coherence.Results The average age in group B was significantly higher than that in group A,and the difference was statistically significant(P<0.05).The average LVIDd and AAO in group B were significantly higher than those in group A and the control group,and the differences were statistically significant(all P<0.05).LSavg,LSepi and LSendo in group A were significantly lower than those in the control group,and the differences were statistically significant(all P<0.05).LSavg,LSepi,LSmid,CSavg,CSepi and CSmid in group B were significantly lower than those in the control group and group A,and the differences were statistically significant(all P<0.05).LSendo and CSendo in group B were significantly lower than those in the control group,and the differences were statistically significant(all P<0.05).The intra-and inter-observer LOA of the longitudinal strain peak and circumferential strain peak in all layers of left ventricular myocardium evaluated by layer-specific myocardial strain were-6.0%~5.0%,and the intra-class correlation coefficient were≥0.80.Conclusion Layer-specific myocardial strain based on echocardiography can be used to assess the cardiac cycle longitudinal peak strain of the left ventricular outer and inner layer in patients with bicuspid aortic valve and normal LVEF,which is beneficial to the early detection of subclinical myocardial injury.