心脏磁共振定量评价缺血性心肌病患者缺血性二尖瓣关闭不全及心肌梗死面积的价值

Value of cardiac magnetic resonance in quantitative evaluation of ischemic mitral regurgitation and myocardial infarction area in patients with ischemic cardiomyopathy

目的分析心脏磁共振(CMR)定量评价缺血性心肌病(ICM)患者缺血性二尖瓣关闭不全(IMR)及心肌梗死面积(MIS)的价值。方法回顾性选择2018年1月至2019年5月上海市第一人民医院收治的85例ICM患者,均给予超声心动图评估、CMR平扫及钆对比剂增强扫描。根据患者治疗方法进行分组:血运重建和MV干预或仅MV干预组(n=34)、仅血运重建组(n=9)、药物治疗组(n=42)。比较其基础资料及CMR成像特点。并在钆增强成像上,MIS被量化为左心室体积,在通过患者屏气相位造影术计算左心室梗死量(由电影图像心内膜分割明确)与主动脉前血流体积间的差值得到磁共振体积(MRVolume),即二尖瓣回流的体积(MRVolume)。用CMR定量计算IMR的二尖瓣返流率(MRFraction)。建立Cox比例风险模型评估IMR和MIS量化。结果85例患者中43例进行血管成形术(其中17例同时进行MV手术干预,2例进行MV置换,15例进行MV修复),42例进行药物治疗。仅血运重建组>2CAD、血管再生pre-CMR发生率高于其余两组,差异有统计学意义(P<0.05);药物治疗组LVMI水平高于其余两组,血运重建和MV干预或仅MV干预组MRFraction、MRVolume水平高于其余两组,差异有统计学意义(P<0.05)。EROA与MRFraction呈正相关(P<0.05);超声心动图评估EROA曲线下面积、CMR评估MRFraction、MRVolume曲线下面积分别为0.635、0.627、0.613,与20%、30%的切点相比,≥35%的MRFraction切点有高度特异性;医疗风险评分、植入心脏除颤器时间、不完整血管再生、MRFraction<35%或≥35%、MIS连续变量、<15%或≥30%是其影响变量(P<0.05)。结论CMR定量评价ICM患者时,MRFraction切点≥35%及MRVolume切点≥25%时均有较高特异性;医疗风险评分、植入心脏除颤器时间、不完整血管再生、MRFraction<35%或≥35%、MIS连续变量、<15%或≥30%是导致患者发生IMR与MIS的风险因素。

Objective To investigate the value of cardiac magnetic resonance(CMR)in quantitative evaluation of ischemic mitral regurgitation(IMR)and myocardial infarction area(MIS)in patients with ischemic cardiomyopathy(ICM).Methods A total of 85 patients with ICM admitted to Shanghai First People's Hospital from January 2018 to May 2019 were retrospectively selected.Echocardiogram,CMR scan and gadolinium-enhanced MRI were performed,respectively.Patients were divided into groups according to the treatment methods:revascularization and MV intervention or MV only intervention group(n=34),revascularization only group(n=9),drug therapy group(n=42).The general data and CMR image characteristics were compared between groups;then the left ventricular infarction volume,volume of mitral regurgitation(MRVolume)and MRFraction were obtained.Cox proportional hazard model was established to evaluate quantification of IMR and MIS.Results Of the 85 patients,42 underwent drug treatment,and 43 underwent angioplasty,including 17 underwent simultaneous MV intervention,2 underwent MV replacement,and 15 underwent MV repair.The incidence rate of>2CAD,revascularization pre-CMR in the only the revascularization group was higher than the other two groups,the difference was statistically significant(P<0.05).The level of LVMI in drug treatment group was higher than that in the other two groups.MRFraction and MRVolume in revascularization-MV intervention group or MV intervention group were higher than those in other two groups,the differences were statistically significant(P<0.05).EROA was positively correlated with MRFraction(P<0.05).The area under the ROC curve of echocardiography and CMR in evaluating EROA,MRFraction and MRVolume was 0.635,0.627 and 0.613,respectively.Compared with 20%and 30%,MRFraction≥35%had higher specificity.Medical risk score,implantation time of cardiac defibrillator,incomplete vascular regeneration,MRFraction<35%or≥35%,MIS continuous variables and MRVolume<15%or≥30%were the influencing variables(P<0.05).Conclusion In the quantitative evaluation of ICM patients by CMR,the specificity of MRFraction≥35%and MRVolume≥25%is relatively high.Medical risk score,implantation time of cardiac defibrillator,incomplete angiogenesis,MRFraction<35%or≥35%,MIS continuous variable,MRVolume<15%or≥30%are risk factors for IMR and MIS.