摘要 |
A heart pump has a pump chamber and a pump element that strokes between a retracted and an extended position. A motor rotates a drive shaft in a single direction. A reversing mechanism coupled between the drive shaft of the motor and the pump element converts rotary motion of the drive shaft to reciprocal stroking movement of the pump element. A mechanical stroke length controller connected to the reversing mechanism varies the stroke length in response to changes in fluid pressure in the pump chamber. |