Effectiveness and limitation of the isolated left ventricular assist system (LVAS) in a model of left and right heart failure and pulmonary hypertension

Abstract

Fifteen mongrel dogs received the isolated LVAS with left ventricular uptake (LV group: 9 dogs) or with left atrial uptake (LA group: 6 dogs). Four of 9 dogs in LV group and 3 of 6 dogs in LA group showed pulmonary hypertension by filariasis. As a model of cardiac failure, left ventricular infarction (LVI) and biventricular infarction (BVI) were made by multiple ligation of coronary arteries. And finally, ventricular fibrillation (VF) was induced with DC fibrillator. High pulmonary vascular resistance (PVR) over 640 dyne·sec·cm^-5 related poor circulatory support during BVI or VF in 3 dogs of LA group and during VF in 4 dogs of LV group. In the remaining 5 dogs with low PVR in LV group, the isolated LVAS with LV uptake was capable of maintaining the sufficient circulation under VF condition.