Motor assembly of active interventional medical device

A motor assembly of an active interventional medical device, comprising:

• a motor body, comprising:
• a rotor assembly comprising a rotor shaft extending in a first direction and a bearing fitted on the rotor shaft,
• a stator assembly fitted on the rotor assembly, a gap between the rotor assembly and the stator assembly forming a first cavity, and
• a housing in which the stator assembly and the rotor assembly are disposed, the rotor shaft being rotatable relative to the housing through the bearing;
• a perfusion catheter in communication with the first cavity, at least part of the perfusion catheter being disposed in the housing;
• and
• a reflux catheter isolated from the perfusion catheter and in communication with the first cavity, at least part of the reflux catheter being disposed in the housing, so that external perfusion solution flows through the perfusion catheter, the bearing, and the reflux catheter in sequence in such a manner that the external perfusion solution flows out of the first cavity.