Evaluation of Optimal Driving Mode during LV Assist with PUCA pump in Calves

The Pulsatile Catheter (PUCA) pump, a left ventricular assist device, was tested during acute experiments in calves using asynchronous and ECG-synchronous assist modes. The aim of the study is to compare ECG-synchronous and asynchronous assist, and to find the optimal driving mode for the PUCA-pump with respect to left ventricular myocardial oxygen consumption (LV MVO2), pump flow, and coronary flow. LV MVO2 decreased significantly during the asynchronous (from 7.77 to 6.46 ml/min/100 gr) as well as during the ECG-synchronous mode (from 8.88 to 7.84 ml/min/100 gr). The pump flow was highest during the ECG-synchronous assist (2.94 L/min), followed by the asynchronous assist (2.79 L/min). The peak coronary flow depended strongly on pump ejection timing and showed the best flow patterns during the ECG-synchronous assist. We concluded that for PUCA pump support both asynchronous and ECGsynchronous assists significantly reduce LV MVO2 and the pump flow generated is enough to maintain the systemic circulation. However, we find the ECGsynchronous mode preferable, because this mode optimizes coronary flow patterns at the same time Artificial Organs 1999, 23:1117-1122