Fluid pump changeable in diameter, in particular for medical application

An intravascular fluid pump device comprising:

• a pump housing having an open distal inflow end, the pump housing being expandable into an expanded state and compressible into a compressed state, wherein, in the compressed state, the pump housing is sized for percutaneous insertion into a vascular system of a patient;
• a drive shaft having a proximal drive side end and a distal portion;
• a radially compressible rotor coupled to the distal portion of the drive shaft, wherein the distal portion of the drive shaft is configured to transmit torque and rotate the radially compressible rotor relative to the pump housing;
• a fixation element carried on the open distal inflow end of the pump housing;
• and
• a bearing assembly coupled to the distal portion of the drive shaft,
• wherein the radially compressible rotor and the bearing assembly are moveable relative to the pump housing in a longitudinal direction of the drive shaft from a first position to a second position, and
• wherein, in the first position, the radially compressible rotor is at least partially disposed exterior to the pump housing, and, in the second position, the radially compressible rotor is disposed within the pump housing and a portion of the bearing assembly is received between a pair of structures disposed on the fixation element.