title: Using hybrid magnetic bearings to completely suspend the impeller of a ventricular assist device.
abstract: Clinically available blood pumps and those under development suffer from poor mechanical reliability and poor biocompatibility related to anatomic fit, hemolysis, and thrombosis. To alleviate these problems concurrently in a long-term device is a substantial challenge. Based on testing the performance of a prototype, and on our judgment of desired characteristics, we have configured an innovative ventricular assist device, the CFVAD4, for long-term use. The design process and its outcome, the CFVAD4 system configuration, is described. To provide unprecedented reliability and biocompatibility, magnetic bearings completely suspend the rotating pump impeller. The CFVAD4 uses a combination of passive (permanent) and active (electric) magnetic bearings, a mixed flow impeller, and a slotless 3-phase brushless DC motor. These components are shaped, oriented, and integrated to provide a compact, implantable, pancake-shaped unit for placement in the left upper abdominal quadrant of adult humans.
authors.affiliation: Artificial Heart Research Laboratory, University of Utah, Salt Lake City 84103, USA.
authors.forename: P
authors.initials: P
authors.lastname: Khanwilkar
authors.forename: D
authors.initials: D
authors.lastname: Olsen
authors.forename: G
authors.initials: G
authors.lastname: Bearnson
authors.forename: P
authors.initials: P
authors.lastname: Allaire
authors.forename: E
authors.initials: E
authors.lastname: Maslen
authors.forename: R
authors.initials: R
authors.lastname: Flack
authors.forename: J
authors.initials: J
authors.lastname: Long
mesh_terms: D001672:Biocompatible Materials; D001696:Biomechanical Phenomena; D001783:Blood Flow Velocity / Q000502:physiology; D004574:Electromagnetic Fields; D004867:Equipment Design / Q000639:trends*; D006353:Heart-Assist Devices; D006461:Hemolysis; D011673:Pulsatile Flow; D013927:Thrombosis / Q000517:prevention & control
chemical_list: D001672:Biocompatible Materials