IN-VITRO EVALUATION OF THE INFLUENCE OF PULSATILE INTRAVENTRICULAR PUMPING ON VENTRICULAR PRESSURE PATTERNS

The Pulsatile catheter (PUCA) pump consists of a single port membrane pump connected to an indwelling valved catheter. This so-called transa rterial blood pump was originally designed to be introduced through a superficial artery into the left ventricular cavity to pump blood from the left ventricle into the ascending aorta. By introducing the cathe ter directly into the thoracic aorta or the pulmonary artery, the poss ibility is created of applying large-diameter catheter PUCA pumps as l eft, right, or biventricular assist devices (LVAD, RVAD, or BIVAD) wit hout damaging any of the structures of the heart. The pump performance of an 8 mm PUCA pump prototype (internal diameter catheter, 8 mm; cat heter length, 40 cm; stroke volume, 80 ml) was studied in a mock circu lation to investigate the influence of pulsatile intraventricular pump ing on ventricular pressure patterns. The pumping mode of the PUCA pum p was changed from approximately 1:1 ([n + 1]:n) to 1:2 ([1/2n + 1]:n) and 1:3 ([1/3n + 1]:n) in relation to the frequency of a ventricle-si mulating membrane pump. Apart from the pumping mode, timing of the PUC A pump driving system (ejection phase) seems to be crucial in obtainin g optimal unloading of the ventricle.