VENTRICULAR ASSIST SYSTEM WITH SECONDARY IMPELLER

摘要

In a centrifugal flow blood pump, usable in left ventricular assist applications, blood is pumped from an inlet ( 16 ) to an outlet ( 22 ) by a primary impeller ( 18 ). A portion of the blood that enters the pump follows a secondary channel ( 24 ) where a secondary impeller ( 70 ) routes the blood to lubricate a bearing between an impeller assembly ( 14 ) and a post formed by a component of the pump housing. The unique shape of the secondary impeller ( 70 ) prevents blood stagnation and provides for a well-washed fluid bearing.