速度向量成像评价糖尿病大鼠早期左心室舒张功能演变规律

Evaluation on progress of early left ventricular diastolic dysfunction in diabetic rats with velocity vector imaging

目的应用速度向量成像(VVI)研究早期糖尿病(DM)大鼠左心室舒张功能障碍的发生、发展过程和演变规律。方法对DM组40只SD大鼠注射链脲佐菌素建立模型。对照组为40只正常大鼠,与DM组体质量相当。于DM模型建成后即刻、2周、4周和8周进行VVI检查,对同一时间点两组间各项舒张功能参数进行比较,同时对组内不同时间点各参数进行比较。结果 VVI指标显示,成模后4周,DM组的舒张期切向应变率较对照组减低,8周时的舒张期切向应变率、切向应变、舒张期径向最大速度均低于对照组,且随病程延长,各参数均有不同程度降低。结论 VVI可较早检出DM大鼠的左心室舒张功能障碍。心肌自身损伤是糖尿病心脏病早期发展阶段的重要改变。

Objective To investigate the progress of early left ventricular diastolic dysfunction with velocity vector imaging（VVI） in diabetic rats.Methods The diabetes mellitus（DM） group comprised 40 male diabetic rats which were induced with streptozotocin.The control group comprised 40 normal male rats with comparable body weights of DM group.All rats underwent VVI immediately and 2 weeks,4 weeks and 8 weeks after diabetic model established.Of each time point,the parameters of left ventricular diastolic function were compared between the 2 groups.In each group,the parameters of different time points were compared.Results Compared with control group,the diastolic circumferential strain rate reduced at 4 weeks and 8 weeks after diabetic model established,the circumferential strain and diastolic velocity reduced at 8 weeks after diabetic model established.The VVI parameters in DM group decreased associated with the diabetic course.Conclusion The early impairment of left ventricular diastolic function in DM rats can be detected with VVI.The phenomenon demonstrates that myocardial impairment play an important role during early stage of DM.