A rotational atherectomy device having, a flexible, elongated, rotatable driveshaft with at least one flexible or partly flexible eccentric enlarged abradinghead At least part of the eccentric enlarged cutting head has an abrasive tissueremoving surface The abrading head may be at least partially hollow When placedwithin an artery against stenotic tissue and rotated at sufficiently high speedsthe eccentric nature of the enlarged cutting head causes the cutting head anddrive shaft to rotate to open the stenotic lesion to a diameter substantiallylarger than the outer diameter of the enlarged cutting head The eccentric enlargedcutting head has a center of mass spaced radially from the rotational axis of thedrive shaft, facilitating opening the stenotic lesion to a diameter substantiallylarger than the outer diameter of the enlarged cutting head when operated at highspeeds
