Pivot wear of a centrifugal blood pump developed for circulatory assist
Related Experiment Video
Updated: Jun 26, 2026

In Vitro Thrombosis Test for Ventricular Assist Devices
Published on: March 21, 2025
Takashi Yamane1, Katsunobu Nonaka, Hisashi Miyoshi
1National Institute of Advanced Industrial Science and Technology, Namiki 1-2-1, Tsukuba 305-8564, Japan. yamane.t@aist.go.jp
Abstract:
We are developing a monopivot centrifugal pump for circulatory assist for a period of more than 2 weeks. The impeller is supported by a pivot bearing at one end and by a passive magnetic bearing at the other. The pivot undergoes concentrated exposure to the phenomena of wear, hemolysis, and thrombus formation. The pivot durability, especially regarding the combination of male/female pivot radii, was examined through rotating wear tests and animal tests. As a result, combinations of similar radii for the male/female pivots were found to provide improved pump durability. In the extreme case, the no-gap combination would result in no thrombus formation.
Related Concept Videos
Centrifugal Force
ATP Driven Pumps III: V-type Pumps
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
Pivot Bearings
A pivot bearing is a specialized type of bearing designed to support axial loads on a rotating shaft. The bearing surface, or the pivot, is positioned at the end of a shaft to support the axial thrust. The pivot may...
Angle of Twist: Problem Solving
ATP Driven Pumps II: P-type Pumps
A typical P-type pump has three cytosolic domains: nucleotide-binding (N), phosphorylation (P), and activator (A) domains. These domains are connected to the membrane-spanning helices by short amino acid segments. ATP hydrolysis and covalent phosphoenzyme intermediate formation are crucial parts of the catalytic cycle. At the highly...
Node Analysis for AC Circuits
To unravel the complexities of this system, nodal analysis is employed, a powerful technique founded on Kirchhoff's current law (KCL), which remains valid for phasors. AC circuits can effectively be...
