左心辅助对心脏功能影响的实验研究

Experimental study of left ventricular assist device (LVAD) on cardiac function

1目的 探讨左心辅助对心脏功能的影响。2方法 实验用成年健康杂种犬 10只 ,随机分为实验和对照组 ,采用结扎左冠状动脉前降支方法建立急性左心衰模型 ,利用气动泵经左心房至升主动脉对心衰犬进行左心辅助 ,以放射免疫学方法测定心衰前、后及应用左心辅助后各时相心脏局部肾素 (RA)活性、血管紧张素 (Ang )的变化。 3结果 两组比较 ,急性左心衰后心脏局部 RA、Ang 水平明显增高 (P<0 .0 5 ) ;左心辅助可显著降低左心局部 RA、Ang 水平 (P<0 .0 5 )。辅助循环初期右心局部 RA、Ang 水平明显降低 (P<0 .0 5 ) ,随辅助时间的延长 ,右心局部 Ang 、RA水平反又增高 ,与心衰前相比 ,差异有显著性 (P<0 .0 5 )。

Objective To explore the effect of LVAD on cardiac function.Methods 10 canines were divided into 2 groups(n=5)assist group and contrast group (which set up LVAD,but no assistance). Acute left heart failure model was induced by ligation the anterior descending branch of left and circumflex coronary artery. Three hours LVAD support was completed by left atrial appendage to ascending aorta bypass with a pneumatic driven diaphragm type left ventricular assist device.The left and right ventricular RA and AngⅡ were measured by radioimmunoassay before and after acute left heart failure and after LVAD at different times for each dog.Results RA and AngII of left and right ventricular were increased significantly after acute left heart failure in all dogs (P<0.05).The level of RA and AngⅡ in left ventricular was decreased significantly after LVAD (P<0.05) compared with after acute left heart failure. The level of RA and AngⅡ in right ventricular was decreased significantly after LVAD at 30,60,120 minutes (P<0.05),but increased at 180 minute (P<0.05) compared with that of acute left heart failure.Conclusions LVAD can improve left ventricular function,but impair right ventricular function in dogs of acute left heart failure. [