心脏磁共振T1Mapping定量分析重度主动脉瓣反流心肌纤维化程度的价值

Cardiac Magnetic Resonance T1 Mapping Quantitative Analysis of Severe Aortic Regurgitation Myocardial Fibrosis

【目的】探讨心脏磁共振(CMR)纵向弛豫时间定量(T1 mapping)技术评估重度主动脉瓣反流(AR)心肌纤维化程度的价值。【方法】选择2018年1月至2020年11月在本院进行CMR成像检查的28例重度AR患者(观察组),选择同期在本院行CMR检查,未发现器质性心脏病者为对照组。比较两组左心室心肌质量(LVMM)、左心室舒张末期容积指数(LVEDVi)、左心室收缩末期容积指数(LVESVi)、左心室每搏输出量容积指数(LVSVi)及左心室射血分数(LVEF)等结构、功能参数及心肌T1值、细胞外间质容积分数(ECV)值,并采用Pearson系数进行相关性分析。【结果】观察组LVEF低于对照组,LVEDVi、LVESVi、LVSVi、LVMM均高于对照组,差异有统计学意义(P<0.05)。延迟强化方面,观察组中有15例患者出现对比剂延迟增强(LGE),对照组中未发现LGE,组间差异有统计学意义(P<0.05)。左心室心肌纤维化方面,观察组初始T1值、ECV均高于对照组,增强后T1值低于对照组,差异有统计学意义(P<0.05)。Pearson相关系数分析显示,初始T1值、ECV值与LVEF呈负相关关系(r=-0.403、-0.400,均P<0.05);增强后T1值与LVEF无明显相关性(r=0.419,P=0.052>0.05)。【结论】CMR T1 mapping技术可反映重度AR患者心肌纤维化程度,且患者心肌纤维化程度与早期心脏重构和左心室收缩功能障碍相关。

【Objective】To explore the application value of T1 mapping quantified with cardiac MR(CMR)in the evaluation of left ventricular systolic function and myocardial fibrosis in severe aortic regurgitation(AR)patients.【Methods】28 patients with severe AR in our hospital from January 2018 to November 2020 and 30 subjects at the same period for physical examination were selected as study group and control group respectively,and they were given cardiac magnetic resonance(CMR)and T1 mapping.The left ventricular myocardial mass(LVMM),left ventricular end diastolic volume index(LVEDVi),left ventricular end systolic volume index(LVESVi),left ventricular stroke volume index(LVSVi),left ventricular ejection fraction(LVEF),initial T1 value,enhanced T1 value and ECV value were compared between the two groups,and Pearson coefficient for correlation analysis.【Results】The LVMM,LVEDVi,LVESVi and LVSVi in study group were higher than those in control group(P<0.05);the LVEF in study group was lower than those in control group(P<0.05);the initial T1 value and ECV in study group were higher than those in control group(P<0.05);Pearson Correlation analysis showed that the initial T1 value and ECV value were negatively correlated with LVEF(P<0.05).【Conclusion】T1 mapping can reflect the diffuse fibrosis of the myocardium in patients with severe AR,which is related to early cardiac remodeling and left ventricular systolic dysfunction to identify subclinical myocardial changes caused by volume overload before clinical symptoms appear.