Compact Ventricular Assist Device and Total Artificial Heart Using Undulation Pump

Fully implantable VAD and TAH are eager to be developed as destination therapy for the severe heart failure patients who do not be candidate of heart transplantation. We have been developing fully implantable VAD and TAH using undulation pump(UP) under multi-institutional cooperative project supported by the Program for Promotion of Fundamental Studies in Health Sciences of the Pharmaceuticals and Medical Device Agency(PMDA). The objective of this presentation is to introduce the present status of their development. UP is a kind of rotary blood pump in which the rotational motion of brushless DC motor is converted to undulation motion of a disc in the pump housing, that squeezes the blood from the inlet to the outlet, and has many advantages; very compact, can produce arbitrary blood flow pattern from pulasatile to continuous, doesn't require heart valve and compliance chamber. UPVAD is composed of UP, undulation shaft and blushless DC motor, which has 69 mm in diameter, 35 mm thick and 331 g of weight. UPTAH is composed of two independent Ups having own undulation shaft and blushless DC motor, which has 76 mm in diameter, 78 mm long and 530 g of weight. TETS has 93 % of DC-DC efficiency. Drive & control unit, lithium-polymer internal batteries and transcutaneous bi-directional information tansmission systemare incorporated into a case having 93x93x40 mm. VAD and TAH could be implanted into the chest cavity of goat weighing between 38 and 79 Kg. In VAD experiments, 4 goats survived for more than 4 weeks with total implantation and 4 months survivors was the longest with only UP implantation. In TAH experiments, 7 goats survived for more than one month. The longest survivors was 63 days. The results show the feasibility of the systems for the future clinical application