抄録
A new pulsatile roller pump based on the concept of intermittent flow produced by one roller instead of two in conjunction with a compliant pump head tube and a pinch valve on the outlet side of the pump head has been developed. The pressure and flow characteristics mimick those of the natural heart, having even the equivalent to the isometric phase and the fast initial ejection of the natural heart. The pump delivers one stroke per each revolution. The stroke volume is a function of the tube size, but for a given size there is an optimal rpm rate at which the stroke volume is largest. Smaller tubes (6 and 9mmID) for use in infants or children have a high optimal rate (100-130/min), while tubes larger than 12.5mmID have an optimal rate of 60-90/min and are suited for use in adults. In vitro mean flows of 10l/min with peak flow velocities reaching 25-27l/min are consistently obtained. The in-vitro hemolysis is similar to that induced by conventional roller pump or the pneumatically driven valved ventricular assist device (Nihon Zeon LVAD) but significantly less (p<0.01) than that induced by the arterial line pulsator (Kontron PBP). Preliminary clinical application in 60 patients has proven its efficacy as a pulsatile pump (pulse pressure of 45 to 65mmHg being consistently obtained), as well as its simplicity and low operational cost.
