左心室脱血回注循环辅助法对急性心肌梗死血流动力学的改善作用

目的:实验观察左心室脱血回注循环辅助法对急性心肌梗死血流动力学的改善作用.方法:18只杂种犬分两组制作急性心肌梗死泵衰竭模型,治疗组给予左心室脱血回注循环辅助,对照组不进行治疗.观察比较两组间心律失常、死亡率、外周动脉压、肺动脉毛细血管楔嵌压(PCWP)、左心室舒张末期压(LVEDP)、左心室内径的变化.结果:治疗组室性期外收缩、心室纤颤发生率和死亡率显著低于对照组;对照组的外周动脉收缩压低于80 mmHg以下,治疗组维持在100mmHg以上(P＜0.01);治疗组PCWP和LVEDP值在45 min以后的各时段低于对照组(P＜0.01);治疗组的左室舒张末期内径小于对照组(P＜0.01).结论:左心室脱血回注循环辅助法能够减少急性心肌梗死泵衰竭的心室纤颤发生率和死亡率,有显著改善血流动力学、防止梗死后心肌扩张和有效的左心室辅助作用.

Therapeutic effects of left ventricular assist device on pump failure caused by acute myocardial infarction

Aim: To evaluate the therapeutic effects of a left ventricular assist device(LVAD) on pump failure caused by acute myocardial infarction(AMI) in dogs. Methods: The pump failure caused by AMI was established in 18 dogs, 9 of them were treated with a LVAD that could expel the autoblood from the left ventricle into the aorta and named the experimental group, and the rest of them were treated with intravenous infusion and served as the control group. The changes of arrhythmia, mortality, pulmonary capillary wedge pressure(PCWP), left ventricular end-diastolic pressure(LVEDP), peripheral artery pressure and the diameter of left ventricular chamber were observed. Results: The ratio of ventricular extrasystole and the mortality resulted from ventricular fibrillation of the experimental group were lower than that of the control group. The systolic blood pressure of peripheral artery of the control group was significantly lower(<100 mmHg) than that of the experimental group (>100 mmHg,P<0.01). The PCWP and LVEDP of the experimental group during all the stages 45 minutes after the procedures were significantly lower than that of the control group(P<0.01). The left ventricular end-diastolic diameter of the control group was larger than that of the experimental groups(P<0.01). Conclusion: To assist circulation by expelling autoblood from left ventricle into aorta in dogs with AMI could reduce the frequency of ventricular fibrillation, improve hemodynamics, and prevent the enlargement of left ventricle. Therefore, it could play an important role in assisting the left ventricular functions.