A rotational atherectomy device for removing a stenotic tissue (330, 360) from a vessel (300) of a patient comprises a flexible hollow drive shaft (2) and an abrasive element (101, 102) mounted to the drive shaft proximal to and spaced from a solid support element (10, 10s) mounted at the distal end (6) of the drive shaft, the solid support element having a rounded outer surface and an outflow channel (20, 20s) with an outflow opening in said rounded outer surface. The drive shaft comprises a torque transmitting coil (4) and at least one fluid impermeable membrane (3) forming a fluid impermeable lumen for the antegrade flow (FF) of fluid into the outflow channel such that, during rotation of the drive shaft, a flow of fluid out of said outflow opening forms a fluid bearing between the rotating solid support element and the wall of the treated vessel.
