A high-speed rotational atherectomy device for opening a stenosis in an artery having a given diameter, comprising: a guide wire having a maximum diameter less than the diameter of the artery; and a flexible elongated, rotatable drive shaft advanceable over the guide wire, the drive shaft having a rotational axis; and at least one eccentric abrading head attached to the drive shaft, the abrading head having a mass, the abrading head mass comprising a distribution, and a nominal resting diameter and comprising proximal, intermediate and distal portions, wherein the proximal portion comprises a proximal outer surface, the intermediate portion comprises an intermediate outer surface, the intermediate portion having a mass located therein, and the distal portion comprises a distal outer surface, the proximal outer surface having diameters that increase distally, the distal outer surface having diameters that decrease distally, and the intermediate outer surface being cylindrical, wherein at least the intermediate outer surface comprises at least one axial groove and at least one non-grooved section, wherein the at least one non-grooved section comprises abrasive coated thereon, wherein the at least one groove comprises abrasive coated thereon, and wherein the abrading head defines a drive shaft lumen therethrough, wherein the drive shaft at least partially traverses the drive shaft lumen, the at least one eccentric abrading head further comprising a geometric center location radially spaced from the drive shaft's rotational axis, a hollowed section within the intermediate portion, the hollowed section lessening the amount of mass within the intermediate portion and affecting the distribution of the amount and location of the mass of the at least one eccentric abrading head, and a center of mass spaced radially from the drive shaft's rotational axis as a consequence of both the geometric center location and the size and shape of the hollowed section within the intermediate portion, wherein the at least one eccentric head is capable of achieving a high-speed rotational diameter that is at least twice as large as the nominal resting diameter of the eccentric abrading head. a guide wire having a maximum diameter less than the diameter of the artery; and a flexible elongated, rotatable drive shaft advanceable over the guide wire, the drive shaft having a rotational axis; and at least one eccentric abrading head attached to the drive shaft, the abrading head having a mass, the abrading head mass comprising a distribution, and a nominal resting diameter and comprising proximal, intermediate and distal portions, wherein the proximal portion comprises a proximal outer surface, the intermediate portion comprises an intermediate outer surface, the intermediate portion having a mass located therein, and the distal portion comprises a distal outer surface, the proximal outer surface having diameters that increase distally, the distal outer surface having diameters that decrease distally, and the intermediate outer surface being cylindrical, wherein at least the intermediate outer surface comprises at least one axial groove and at least one non-grooved section, wherein the at least one non-grooved section comprises abrasive coated thereon, wherein the at least one groove comprises abrasive coated thereon, and wherein the abrading head defines a drive shaft lumen therethrough, wherein the drive shaft at least partially traverses the drive shaft lumen, the at least one eccentric abrading head further comprising a geometric center location radially spaced from the drive shaft's rotational axis, a hollowed section within the intermediate portion, the hollowed section lessening the amount of mass within the intermediate portion and affecting the distribution of the amount and location of the mass of the at least one eccentric abrading head, and a center of mass spaced radially from the drive shaft's rotational axis as a consequence of both the geometric center location and the size and shape of the hollowed section within the intermediate portion, wherein the at least one eccentric head is capable of achieving a high-speed rotational diameter that is at least twice as large as the nominal resting diameter of the eccentric abrading head.