Apparatus and method for rotational atherectomy

Apparatus for performing an atherectomy, comprising:

• a rotational atherectomy device having a flexible, elongated drive shaft, an abrasive burr carried on the drive shaft, the drive shaft and abrasive burr each including a central lumen therein for receipt of a guide wire, and a catheter in which the drive shaft is disposed, the catheter and the guide wire each having an outer surface;
• and
• a guide wire having a flexible, generally straight proximal portion, a flexible distal end portion, each such portion having a longitudinal axis, and a flexible intermediate burr-positioning segment, the burr-positioning segment being made of a shape-memory alloy and having a predetermined curved shape, which is generally co-planar, such that when the abrasive burr is advanced over the guide wire to a position along the curved burr-positioning segment, such curved segment positions the burr laterally away from the longitudinal axes of the proximal and distal end portions;
• the curve of the guide wire's burr-positioning segment being configured so that the axes of the portions of the guide wire which are located just proximal and distal to the intermediate burr-positioning segment are offset from each other by an amount generally equal to the cross-sectional distance, measured at the distal end of the catheter, between the outer surface of the guide wire and the outer surface of the catheter.

A method of removing a stenosis from an artery comprising the steps of:

• (a) providing a rotational atherectomy device having a flexible, elongated drive shaft with an abrasive burr carried on the drive shaft, the drive shaft and abrasive burr each including a central lumen therein for receipt of a guide wire;
• (b) providing a guide wire having a flexible, generally straight proximal portion, a flexible distal end portion, each such portion having a longitudinal axis, and a flexible intermediate burr-positioning segment having a predetermined curved shape;
• (c) advancing the guide wire across the stenosis in the artery and positioning the burr-positioning segment of the guide wire near stenotic tissue to be removed;
• (d) advancing the burr with its flexible drive shaft along the guide wire to a position along the burr-positioning segment, generally just proximal to the stenotic tissue to be removed, such burr-positioning segment thereby positioning the burr laterally away from one or both of the longitudinal axes of the proximal and the distal end portions of the guide wire;
• (e) rotating the guide wire, if necessary, to position the burr at a desired location adjacent to the tissue to be removed;
• and
• (f) rotating the drive shaft and burr while advancing and retracting the burr and drive shaft to remove the tissue.