健康猪左室功能MR测定及多巴酚丁胺负荷实验研究

Healthy swine study of left ventricular function and stress test with MR cine imaging

目的:应用MR电影成像评价健康猪左室功能和多巴酚丁胺负荷实验。方法:对9只健康小型猪行MR电影成像测量左室容量和心肌质量,并比较静息状态和负荷状态下心肌增厚率的变化。结果:在垂直于室间隔的左室短轴MR电影图像上测量左室舒张末期容量(LVEDV)体重()为(BW2.4±0.3mlkg,左室收缩末期容量()LVESV)BW为(1.1±0.1ml)kg,左室心肌质量(LVM)BW为(3.03±0.21mlkg,射血分数()为()EF55±3%)。小剂量多巴酚丁胺[5μg(·min),10kg(μgkg·min)]能增加正常心肌收缩力,使左室收缩期心壁厚度和左室心肌增厚率较静息状态有显著增加。结论:心脏电影MR图像分辨率高,可测定心功能多项指标,小剂量多巴酚丁胺静滴安全,并能够增加心肌收缩力。

Objective: To evaluate left ventricular function in healthy swine and stress test with MR cine imaging. Methods: Nine healthy swine were studied with cine MR imaging, and the left ventricular function and mass were measured, then the left ventricular wall thickness and the thickening between systolic and diastolic phase were compared between rest state and stress test state. Results: Measuring in the vertical inter-ventricular spetum short-axis cine MR images of the left ventricular, the value of LVEDV/BW was (2.4±0.3)ml/kg, LVESV/BW was (1.1±0.1)ml/kg, LVM/BW was (3.03±0.21)ml/kg, EF was (55±3)%. Low dose dobutamine[5μg/(kg·min), 10μg/(kg·min)] can improve myocardial contraction, the left ventricular wall thickness and wall thickening were significantly increased with two dose dobutamine test. Conclusion: MR cine imaging have high resolution, can evaluate almost all indexes of cardiac function, low dose dobutamine can improve myocardial contraction.