A rotational atherectomy device for removing a stenotic tissue from a vessel of a patient is disclosed. The device comprises a rotatable, flexible, hollow drive shaft having a fluid impermeable wall defining a lumen of the drive shaft and, an abrasive element mounted to a distal end portion of the drive shaft proximal to and spaced away from a distal support element formed at a distal end of the drive shaft. The distal support element is inflatable by pressurized fluid which flows in an antegrade direction through said lumen of the drive shaft and is least partially re-directed into the distal fluid inflatable support element. The distal fluid inflatable support element has an outer wall comprising an outflow opening located such that said outflow opening faces an inner surface of a treated vessel during rotation of the drive shaft so that a flow of fluid through said outflow opening forms a layer of fluid between the outer wall of the rotating fluid inflated distal support element and a wall of the treated vessel to form a fluid bearing between the outer wall of the rotating fluid inflated distal support element and the wall of the treated vessel. The fluid impermeable drive shaft comprises at least one torque transmitting coil and at least one fluid impermeable membrane which extends beyond a distal end of the torque transmitting coil and conveys torque to the abrasive element mounted to the drive shaft distal to and spaced away from the distal end of the torque transmitting coil.
