Abstract: An expandable and compressible atherectomy cutter for cutting plaque from a stenosis in an artery includes a cutter assembly which, relative to its axis of rotation, has a plurality of radially separated and axially aligned blades. The distal ends of these blades are joined together at a grommet and the proximal ends are free for individual engagement with grooves which are axially oriented on the hub of a rotatable torque tube. Each groove on the hub has a plurality of notches, and each notch in a groove has a corresponding notch in each of the other grooves which lies in the same radial plane and at the same radial distance from the rotational axis of the torque tube. Although notches in different radial planes can have different radial distances, the proximal ends of the blades simultaneously engage with only the notches in the same radial plane.

Abstract: A rotationally expandable atherectomy cutter assembly for cutting plaque from a stenosis in an artery includes a plurality of radially separated and axially aligned blade elements. The distal ends of each blade element are fixably connected to a hub and the proximal ends of each blade element slidably engage helical slots formed in a distally flared extension tube of the assembly. The extension tube is connectable to a rotatable catheter. The helical slots are oriented in a first direction such that contact of the cutter assembly with the plaque of the stenosis, in conjunction with a second direction rotation of the catheter causes the proximal ends of the blade assembly to slide distally along the helical slots thereby expanding the cutting radius of the cutter assembly.

Abstract: A balloon expandable atherectomy cutter for removing plaque from an artery includes an elongated cutter assembly having a plurality of blades which, with respect to the axis of rotation of the cutter, are radially separated from each other and axially aligned with each other. The assembly is mounted on the distal end of a rotatable catheter and is rotatable about a quide wire to cut plaque from an artery as it is rotated. An inflatable balloon, is mounted between an ovoid space formed between the blades. An inflator is connected with the balloon to inflate the balloon and urge it against the distal portion of the blades. In the operation of the cutter, when the balloon is deflated the blades establish a first radius of rotation which cuts through the plaque of a stenotic segment as the cutter is advanced into the artery.