心脏MRI评估法洛四联症和肺动脉瓣狭窄术后患儿左心房功能的价值

Value of cardiac MRI in evaluation of left atrial function in the postoperative tetralogy of Fallot and pulmonary stenosis patients

目的探讨心脏MRI评估法洛四联症(TOF)和肺动脉瓣狭窄(PS)术后患儿左心房功能的价值。方法回顾性分析2019年1月至2021年10月于上海交通大学医学院附属上海儿童医学中心接受心脏MRI的左心室射血分数保留的TOF和PS术后患者67例,其中TOF术后组49例、PS术后组18例。2017年7月至2018年8月间收集与患儿性别、年龄匹配的正常志愿者33例为对照组。基于心脏MRI图像,采用心功能分析软件获得左心房功能参数,包括储存期、管道期、收缩期的射血分数、应变、应变率;测量左心房容积指数,包括左心房最大容积指数、最小容积指数及收缩前容积指数。采用单因素方差分析或Kruskal-Wallis检验比较3组间的差异,两两比较采用事后比较及Bonferroni校正。结果与对照组比较,TOF术后患儿的储存期射血分数、储存期应变、储存期应变率、管道期射血分数、管道期应变和左心房最大容积指数均下降(P<0.05),收缩期射血分数升高(P>0.05)。与对照组比较,PS术后组仅储存期应变率下降(P<0.05),余左心房功能参数和容积指数差异均无统计学意义(P>0.05)。PS术后组储存期及管道期的射血分数及应变均高于TOF术后组(P<0.05)。结论在左心室射血分数保留的TOF和PS术后患儿中,左心房功能已发生异常。TOF术后患儿的左心房储存功能和管道功能均下降,收缩功能增加;PS术后患儿的左心房储存和管道功能优于TOF术后患儿。心脏MRI可以在左心房结构扩大之前,早期发现左心房的功能异常。

Objective To explore the value of cardiac MRI(CMRI)in evaluating left atrial function in patients with postoperative tetralogy of Fallot(rTOF)and postoperative pulmonary stenosis(rPS).Methods Totally 67 pediatric patients(49 with rTOF,18 with rPS)with preserved left ventricular ejection fraction(EF)were recruited between January 2019 and October 2021 in Shanghai Children′s Medical Center,School of Medicine,Shanghai Jiao Tong University.Thirty-three healthy volunteers,matched in gender and age,were included as controls from July 2017 to August 2018.Left atrial EF,strain and strain rate of three phases(reservoir,conduit and pump),left atrial volume(maximum volume index,minimum volume index and pre-atrial contraction volume index)were measured with corresponding cardiac function analysis software.Then,the differences in these parameters were analyzed between the three groups by ANOVA or Kruskal-Wallis test with post hoc comparison and Bonferroni correction.Results Compared with controls,patients with rTOF had lower reservoir function parameters(EF,strain and strain rate),conduit EF,conduit strain,and left atrial maximum volume index(P<0.05),but higher pump EF(P<0.05).In patients with rPS,only the reservoir strain rate decreased compared with controls(P<0.05),and the remaining data showed no significant difference(P>0.05).The reservoir and conduit EF and strain in patients with rPS were higher than those in patients with rTOF(P<0.05).Conclusions In patients with rTOF and rPS,left atrial function has changed despite the preservation of left ventricular EF,which may be an early marker of left ventricular diastolic dysfunction.In children with rTOF,left atrial reservoir and conduit functions decreased while the pump function increased.The reservoir and pump functions in rPS were better than those in rTOF.In addition,CMRI can detect left atrial dysfunction early before it enlarged.