CHRONIC IN-VIVO HEMODYNAMIC STUDY OF THE PEDIATRIC JARVIK 2000 HEART:

Objective: The pediatric Jarvik 2000 heart is currently being developed for pediatric mechanical circulatory support. It is based on an intraventricular axial flow pump utilizing an apical placement with an aortic outflow graft. The pump weighs 35 grams and measures 17.8 mm in diameter with a length of 7.5 cm. The purpose of this study is to investigate the chronic hemodynamic performance of the pediatric Jarvik 2000 heart in the pediatric setting. Methods: The pediatric Jarvik 2000 heart was implanted for 30 days in 4 lambs (age: 10 weeks; weight: 18 to 25 kg) through a left thoractomy incision. The pump was placed into the left ventricle through an apical insertion. The outflow graft was anastomosed to the descending aorta. Two transonic flow probes were placed around the main pulmonary artery and the outflow graft. Cardiac output and pump flow were measured daily post-implantation at five pump speeds from 10,000 rpm to 14,000 rpm. Results: In all 4 lambs, the pediatric Jarvik 2000 fit comfortably into the thoracic cavity. All animals tolerated the procedure and were subsequently recovered. The flow through the outflow graft at five speeds from 10,000 rpm to 14,000 rpm were 1.57 ± 0.35, 1.94 ± 0.39, 2.33 ± 0.44, 2.72 ± 0.57 and 2.90 ± 0.59 (L/min). This flow corresponded with 40.3 ± 8.1, 50.1 ± 8.0, 59.6 ± 7.4, 69.1 ± 6.1, and 73.8 ± 4.2 (%) of the total cardiac output. Conclusions: The pediatric Jarvik 2000 heart can provide partial to near complete circulatory support in small pediatric animals.