METHOD AND APPARATUS FOR INCREASING ROTATIONAL AMPLITUDE OF ABRASIVE ELEMENT ON HIGH-SPEED ROTATIONAL ATHERECTOMY DEVICE

摘要

A high-speed atherectomy device is disclosed, for abrading a blockage(stenosis) in the interior of a lumen (artery).The device uses a rapidly rotating drive shaft that includes an eccentricabrasive element that has its center of mass laterally offsetfrom the rotational axis of the drive shaft. As the drive shaft rotates,centrifugal force drives the eccentric abrasive element outward,so that it traces an abrading diameter at high rotational speeds that islarger than its rest diameter. The drive shaft includescounterweights on both sides of the abrasive element, which may stabilizeoperation at high rotational speeds. In some cases, thecounterweights are also eccentric, with their centers of mass laterally offsetfrom the rotational axis in the opposite direction asthat of the abrasive element. The counterweights are longitudinally separatedfrom the abrasive element, and in some cases, theseparations are adjustable and/or controllable. In some cases, the guide wiremay be retracted prior to or during the high-speed rotationof the drive shaft, with the retraction being to the distal counterweight, theabrasive element, the proximal counterweight, orbeyond the proximal counterweight.