Purging a bearing interface

An apparatus for use with a purging fluid, the apparatus comprising:

• a left-ventricular assist device comprising a pump head that comprises:
• an axial shaft;
• a radially-expandable impeller coupled to the axial shaft and configured to be deployed within a left ventricle of a subject;
• and
• a proximal radial bearing disposed around the axial shaft proximally to the impeller, and a distal radial bearing disposed around the axial shaft distally to the impeller,
• the left-ventricular assist device defining a purging-fluid lumen configured to direct the purging fluid to an interface between the axial shaft and the distal radial bearing, thereby purging the interface between the axial shaft and the distal radial bearing.