Patent · US Expired

Anti-thrombogenic blood pump

US4704121A · kind A · utility

329Cited by
6References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 28, 1983
Grant dateNov 3, 1987
Priority date
Expiry dateSep 28, 2003

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61M60/148
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

Thrombus formation in an implantable blood pump is prevented by using a close-tolerance purge seal for the impeller shaft or rotor. A blood-compatible fluid is used for the purge fluid (which is preferably also the bearing fluid), and the purge flow into the blood stream presents to the blood stream a benign interface between the rotating and stationary parts of the pump. The rotating and stationary surfaces adjacent the interface are so configured as to present an essentially continuous smooth surface across the interface which can be swept by the blood stream and presents no cavities in which the blood can stagnate. The close clearances of the purge seal allow a sufficient purge flow rate to be maintained with only a minute amount of purge fluid; and in accordance with one aspect of the invention, the purge fluid can be derived from the blood stream by a protein-filtering membrane system so that no external replenishment of the purge fluid supply is necessary.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.