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

• US 20090264908A1
• Filed: 03/17/2009
• Published: 10/22/2009
• Est. Priority Date: 04/18/2008
• Status: Active Grant

• Current Assignee: Cardiovascular Systems Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiovascular Systems Incorporated (Boston Scientific Corporation)
• Inventors: Kallok, Michael J., Petrucci, Gary M.
• Granted Patent: US 8,177,801 B2
• Time in Patent Office: Days
• US Class Current: 606/159
• CPC Class Codes: A61B 17/320758 with a rotating cutting instrument, e.g. motor driven A61B17/320725, A61B17/32075 and A61B17/320783 take precedence; for removing intra-ocular material A61F9/00763; endoscopic rotatable cutting instruments A61B17/32002
• CPC Class Codes: A61B 2017/22042 Details of the tip of the guide wire
• CPC Class Codes: A61B 2017/320004 abrasive
• CPC Class Codes: A61B 2017/320766 eccentric

Abstract

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 eccentric abrasive element that has its center of mass laterally offset from 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 is larger than its rest diameter. The drive shaft includes counterweights on both sides of the abrasive element, which may stabilize operation at high rotational speeds. In some cases, the counterweights are also eccentric, with their centers of mass laterally offset from the rotational axis in the opposite direction as that of the abrasive element. The counterweights are longitudinally separated from the abrasive element, and in some cases, the separations are adjustable and/or controllable. In some cases, the guide wire may be retracted prior to or during the high-speed rotation of the drive shaft, with the retraction being to the distal counterweight, the abrasive element, the proximal counterweight, or beyond the proximal counterweight.

Claims

1. 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;

a flexible, elongated, rotatable drive shaft advanceable over the guide wire;

an abrasive element disposed on the drive shaft;

a proximal counterweight attached to the drive shaft and spaced apart proximally from the abrasive element by an adjustable proximal spacing; and

a distal counterweight attached to the drive shaft and spaced apart distally from the abrasive element by an adjustable distal spacing.

2. The high-speed rotational atherectomy device of claim 1,

wherein the proximal counterweight is removably clampable to the drive shaft,

wherein the proximal counterweight is clamped to the drive shaft for high-speed rotation of the drive shaft, and

wherein the proximal counterweight is unclamped for adjustment of the proximal spacing, the adjustment occurring at low-speed rotation or non-rotation of the drive shaft.

3. The high-speed rotational atherectomy device of claim 2, wherein the proximal counterweight is slidable along the drive shaft when the proximal counterweight is unclamped.

4. The high-speed rotational atherectomy device of claim 1,

wherein the distal counterweight is removably clampable to the drive shaft,

wherein the distal counterweight is clamped to the drive shaft for high-speed rotation of the drive shaft, and

wherein the distal counterweight is unclamped for adjustment of the distal spacing, the adjustment occurring at low-speed rotation or non-rotation of the drive shaft.

5. The high-speed rotational atherectomy device of claim 4, wherein the distal counterweight is slidable along the drive shaft when the distal counterweight is unclamped.

6. A method for abrading a blockage in the interior of an artery, comprising:

providing a guide wire with a diameter less than the diameter of the artery;

providing a flexible, elongated, rotatable drive shaft advanceable over the guide wire, the drive shaft having a rotational axis and an eccentric abrasive element;

providing a proximal counterweight spaced a distance proximally from the eccentric abrasive element;

providing a distal counterweight spaced a distance distally from the eccentric abrasive element;

retracting the guide wire; and

rotating the drive shaft at high speed.

7. The method of claim 6, further comprising retracting the guide wire to the distal counterweight.

8. The method of claim 6, further comprising retracting the guide wire to the eccentric abrasive element.

9. The method of claim 6, further comprising retracting the guide wire to the proximal counterweight.

10. The method of claim 6, further comprising retracting the guide wire beyond the proximal counterweight.

11. The method of claim 6, wherein the abrasive element comprises an eccentric enlarged section of the drive shaft.

12. The method of claim 6, wherein the abrasive element comprises an eccentric abrasive crown attached to the drive shaft.

13. The method of claim 6, wherein the at least one of the proximal and distal counterweights comprises an eccentric enlarged section of the drive shaft.

14. The method of claim 6, wherein the at least one of the proximal and distal counterweights comprises an eccentric element attached to the drive shaft.

15. The method of claim 6, wherein the at least one of the proximal and distal counterweights comprises a concentric enlarged section of the drive shaft.

16. The method of claim 6, wherein the at least one of the proximal and distal counterweights comprises a concentric element attached to the drive shaft.

17. The method of claim 6, wherein the distal counterweight and the proximal counterweight are both concentric.

18. The method of claim 6, wherein the guide wire is retracted prior to rotating the drive shaft at high speed.

19. The method of claim 6, wherein the guide wire is retracted while the drive shaft is rotated at high speed.

20. A method for abrading a blockage in the interior of an artery, comprising:

providing a guide wire with a diameter less than the diameter of the artery;

providing a flexible, elongated, rotatable drive shaft advanceable over the guide wire, the drive shaft having a rotational axis and an eccentric abrasive element, the abrasive element comprising an eccentric enlarged section of the drive shaft;

providing a proximal counterweight spaced a distance proximally from the eccentric abrasive element, the proximal counterweight comprising an eccentric enlarged section of the drive shaft;

providing a distal counterweight spaced a distance distally from the eccentric abrasive element, the distal counterweight comprising an eccentric enlarged section of the drive shaft;

retracting the guide wire; and

rotating the drive shaft at high speed.