[Experimental study on hemodynamic and cardiac effects of counterpulsatile blood flow assisted IABP for acute left ventricular failure].

The purpose of this study is to evaluate the effect of newly developed balloon pumping system with synchronized blood flow assist for acute left ventricular failure. In 21 mongrel dogs with left heart failure following left coronary artery ligation, counterpulsatile flow assisted IABP (CFA-IABP) was instituted changing the flow rate from 5% to 70% of the aortic flow at control. The following results were obtained. 1) CFA-IABP significantly increased aortic, carotid, and coronary sinus flows as well increased aortic pressure and endocardial viability ratio, and also reduced left atrial pressure, LVEDP and myocardial oxygen uptake at the low flow assist of about 20% of aortic flow at control. 2) In high flow assist of more than the 50%, the effect of CFA-IABP was present but limited. 3) There was no change of hemodynamics and cardiac function at the timing of CFA method during the diastolic phase. 4) There was no statistically significant difference between CFA and constitute (non-pulsatile) flow assist, but CFA tended to much improve hemodynamics and cardiac function.