Apical aortic blood pump preclinical assessment for long-term use: Durability test and stator topology to reduce wear in the bearing system.

This study presents an assessment for long-term use of the apical aortic blood pump (AABP), focusing on wear reduction in the bearing system. AABP is a centrifugal left ventricle assist device initially developed for bridge to transplant application. To analyze AABP performance in long-term applications, a durability test was performed. This test indicated that wear in the lower bearing pivot causes device failure in long-term. A wear test in the bearing system was conducted to demonstrate the correlation of the load in the bearing system with wear. Results from the wear test showed a direct correlation between load and wear at the lower bearing pivot. In order to reduce load, thus reducing wear, a new stator topology has been proposed. In this topology, a radial stator would replace the axial stator previously used. Another durability test with the new stator has accounted twice the time without failure when compared with the original model.