AIMTo evaluate the therapeutic effects of a left ventricular assist device (LVAD) on pump failure caused by acute myocardial infarction (AMI) in dogs.

METHODSThe 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.

RESULTSThe 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).

CONCLUSIONTo 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.