自发性2型糖尿病恒河猴双心室形变的心脏磁共振分析

  目的  利用心脏磁共振组织追踪技术(CMR-tissue tracking)探讨自发性2型糖尿病(T2DM)恒河猴双心室的心肌形变特征。  方法  选取12只雄性自发性T2DM恒河猴以及9只年龄、性别及体质量匹配的健康恒河猴，排除高血压、心肌梗死；测定空腹血糖、糖化血红蛋白水平以及血脂水平；行CMR扫描覆盖左、右心室的电影序列，使用常规心功能分析及CMR-tissue tracking后处理评价双心室的心功能以及心肌形变。  结果  T2DM组空腹血糖及糖化血红蛋白水平明显增高，两组间体质量、年龄差异无统计学意义。心功能分析显示T2DM组双心室射血分数均无显著降低；组织追踪结果显示右室自由壁的收缩形变参数〔包括径向及环向应变峰值(Err、Ecc)、收缩期应变率峰值(SSRR、SSRC)的大小〕均明显降低，舒张形变参数〔包括径向、环向和纵向舒张期应变率峰值(DSRR、DSRC、DSRL)的大小〕均显著降低；而左室的收缩形变参数〔径向及环向应变峰值(Err、Ecc)〕以及舒张形变参数〔径向舒张期应变率峰值(DSRR)〕显著降低。  结论  CMR-tissue tracking技术能发现自发性T2DM恒河猴的右心室与左心室同时存在收缩及舒张形变功能的异常。

Cardiac Magnetic Resonance Imaging Study of Ventricular Myocardial Deformation in Spontaneous T2DM Rhesus Monkey

  Objective   To assess biventricular, especially right ventricular, function and deformationin rhesus monkeys with spontaneous type 2 diabetes mellitus (T2DM) using cardiac magnetic resonance (CMR).  Methods   Twelve male spontaneous T2DM rhesus monkeys and age, sex, body mass matched 9 healthy rhesus monkeys without hypertension and myocardial infarction were included in this study. Fasting blood glucose (FPG), glycated hemoglobin (HbA1c) and blood liquid levels were measured. Biventricular function and myocardial deformations were evaluated by CMR cine and tissue-tracking.  Results   Compared with control, the FPG and HbA1c levers were significantly increased in T2DM group, but there was no significant difference in body mass and age between the two groups. CMR result showed that there was no significant decrease in right ventricle and left ventricle ejection fraction in T2DM (P < 0.05). However, the absolute value of radial and circumferential global peak systolic strain, systolic strain rate and three directions global peak diastolic strain rate of the right ventricle free wall were lower in the T2DM group (P < 0.05). Also, only radial and circumferential peak systolic strain and radial diastolic strain rate of left ventricle were higher (P < 0.05).  Conclusion   Right ventricle showed systolic and diastolic dysfunction which were consistent with left ventricle in T2DM by CMR-tissue tracking.