IN VIVO EVALUATION OF “ANYHEART” AS A TAH AND BIVAD IN CALVES

Abstract

An AnyHeart (BioMedlab. Seoul, Korea) is an implantable blood pump with an electromechanical actuation system and is designed for multipurpose use as a TAH, LVAD, RVAD or BiVAD. The pump is unique in that the use of active pump filling allows a high pumping rate (up to 270 BPM) without compromising the pump filling. To validate this concept, a prototype AnyHeart was implanted in calves (BW: 75–85 kg) either in a TAH (n = 2) or BiVAD (n = 2) configuration assessing implantation technique and comparative hemodynamic performance. As a TAH the pump fit well in the pericardial sac without any anatomic compromise. With 4 conduits (15–23 cm long, 1.2 cm diameter) the pump was implanted with ease in the right chest as a BIVAD. The pumping and right-left balancing were accomplished with an interventricular space pressure based automatic control logic. In a TAH configuration, with physiologic atrial pressures (LAP: 10.6 ± 4.0 mmHg, RAP: 12.7 ± 5.1 mmHg) the average outflow obtained was 5.1 and 6.9 L/min in each case with respective efficiency of 19.8% and 16.4 %. The maximum flow of 10.4 L/min was obtained with a pump rate of 269 BPM while maintaining an excellent right-left flow balance. When used as a BiVAD, the outflow was decreased, relative to the expected in vitro flow, to 3.9 L/min with 9.2% efficiency due to kinking and subsequent thrombus formation in the inflow conduits. The kinking problem was, however, deemed easily solvable by selecting proper material with proper reinforcement to obtain the maximum flow of 8.9 L/min as demonstrated in vitro. The present study dearly showed the feasibility of a multipurpose pump concept. Further in vitro and in vivo validation is underway to optimize the implantation technique, conduit design and compliance cap needed for the RAVD and LVAD configurations. This work was supported by the BK21 project