A rotational atherectomy device having, a flexible, elongated, rotatable drive shaft with at least one flexible or partly flexible eccentric enlarged abrading head At least part of the eccentric enlarged cutting head has an abrasive tissue removing surface The abrading head may be at least partially hollow When placed within an artery against stenotic tissue and rotated at sufficiently high speeds the eccentric nature of the enlarged cutting head causes the cutting head and drive shaft to rotate to open the stenotic lesion to a diameter substantially larger than the outer diameter of the enlarged cutting head The eccentric enlarged cutting head has a center of mass spaced radially from the rotational axis of the drive shaft, facilitating opening the stenotic lesion to a diameter substantially larger than the outer diameter of the enlarged cutting head when operated at high speeds