Clinically practical rotational angioplasty system

• US 5,314,407 A
• Filed: 07/21/1992
• Issued: 05/24/1994
• Est. Priority Date: 11/14/1986
• Status: Expired due to Term

• Current Assignee: Boston Scientific Corporation Northwest Technology Center Inc. (Boston Scientific Corporation)
• Original Assignee: Heart Technology, Inc. (Boston Scientific Corporation)
• Inventors: Auth, David C., Hinchcliffe, John S., Slota, Michael W., Intlekofer, Michael J., Clement, Thomas J.
• Primary Examiner(s): Thaler, Michael H.
• Application Number:
  US07/917,923
• Time in Patent Office: 672 Days
• Field of Search: 604/22, 606/159, 606/180, 128/751-755
• US Class Current: 604/22
• 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

Abstract

The present invention is a clinically practical, rotational angioplasty system which employs a unique rotary ablative device for mechanically abrading, and thereby removing, lesions from within a patient'"'"'s vessels. The device has a gas driven prime mover connected, via a hollow helical drive assembly, to an ellipsoidal, rotating, ablative burr which is used for the actual recanalization of the patient'"'"'s vessel. The burr is provided with a central opening therethrough, which, together with the hollow drive assembly, permits the burr and drive assembly to be threaded over a guide wire similar to the type conventionally used in a catheterization procedure. The drive assembly is located within a hollow sheath which prevents the rotating drive assembly from contacting the inner walls of a patient'"'"'s vessel.

Claims

1. A gas driven, rotary ablative apparatus for medical applications comprising:

(a) a body having an advancer assembly which can be moved between a proximal position and a distal position;

(b) a gas driven prime mover within said advancer assembly and movable therewith, said gas driven prime mover having a shaft which is attached to a first end of a rotatable, flexible, hollow, high-speed drive shaft;

(c) an ablative burr attached to the second end of said flexible, hollow, high-speed drive shaft and movable between proximal and distal positions with said advancer assembly, said advancer assembly cooperating with said prime mover such that said ablative burr can be rotated at high speed while being advanced;

(d) a flexible sheath which extends from one end of said body substantially along the length of said drive shaft, forming a lumen between said drive shaft and said sheath, whereby the inner walls of a patient'"'"'s vessel into which said drive shaft is inserted will be isolated from said rotating drive shaft by said sheath; and

(e) a water pump having a shaft connected to the prime mover drive shaft, the output of the water pump being in fluid connection with the lumen between said drive shaft and said sheath.

2. A gas driven, rotary ablative apparatus for medical applications comprising:

(a) a body having an advancer assembly which can be moved between a proximal position and a distal position;

(b) a gas driven prime mover within said advancer assembly and movable therewith, said gas driven prime mover having a shaft which is attached to a first end of a flexible, hollow, high speed drive;

(c) a rotating ablative burr attached to the second end of said flexible, hollow, high-speed drive and movable between proximal and distal positions with said advancer assembly;

(d) a flexible sheath which extends from one end of said body substantially along the length of said drive, whereby the inner walls of a patient'"'"'s vessel into which said drive is inserted will be isolated from said rotating drive by said sheath; and

(e) a water pump within said advancer assembly and movable therewith having a shaft connected to said prime mover shaft, the output of said water pump being connected to a lumen formed between said drive and said sheath.

3. The apparatus of claim 2, wherein said drive is comprised of a helical, spring-like winding.

4. The apparatus of claim 3, wherein said gas driven prime mover has a hollow shaft and said burr includes a central opening, whereby said burr and said drive can be fed along a guide wire into a patient'"'"'s vessel.

5. The apparatus of claim 4, wherein said body includes brake means for preventing movement of said guide wire.

6. The apparatus of claim 5, wherein said brake means includes a brake knob which can be screwed into said body, a flexible tube through which said guide wire passes within said body, and a brake plunger which exerts pressure on said tube when said brake knob is screwed onto said body.

7. The apparatus of claim 4, wherein there is an atraumatic tip at the distal end of said guide wire, said atraumatic tip being adapted for ensnaring fibrin within a clot within a patient'"'"'s vessel.

8. The apparatus of claim 7, wherein means for rotating said atraumatic tip is attachable to the proximal end of said guide wire.

9. The apparatus of claim 2, further comprising a fiberoptic tachometer, said fiberoptic tachometer comprising:

(a) a tachometer rotor mounted on said prime mover shaft, said tachometer rotor having at least one reflective area thereon;

(b) a pair of fiberoptic cables, one of which shines light onto said at least one reflective area, the other one of which carries reflected light pulses from said tachometer rotor; and

(c) means for obtaining a count of said reflected light pulses and converting said count into revolutions per minute.

10. The apparatus of claim 9, wherein said body includes a slot formed therein for moving said advancer assembly within said body.

11. The apparatus of claim 10, wherein said advancer assembly includes means for attaching an air hose, a fiberoptic cable, and a source of infusate thereto.

12. The apparatus of claim 11, wherein said body has a slot formed therein for attaching said air hose, said fiberoptic cable, and said source of infusate.

13. The apparatus of claim 12, further comprising a lock means for locking the position of said advancer assembly within said body.

14. The apparatus of claim 13, further comprising a fixed front support means and a fixed rear support means within said body, said support means being adapted to define the distal and proximal limits of travel of said advancer assembly.

15. The apparatus of claim 14, wherein said advancer assembly includes tube means surrounding said drive and slidable over fixed tube means attached to said front and rear support means, whereby a continuous, sealed, telescopic tube extends from said advancer assembly to said sheath.

16. The apparatus of claim 12, further comprising means remote from said body for measuring the rotational speed of said gas driven prime mover.

17. The apparatus of claim 16, wherein said means for measuring the rotational speed of said gas driven prime mover comprises:

(a) a light supply means for supplying light through a first fiberoptic cable attached to said advancer assembly;

(b) light detecting means for counting light pulses arriving on a second fiberoptic cable attached to said advancer assembly; and

(c) converting means for converting said count into a measure of revolutions per minute by dividing said count per unit time by the number of reflective areas on said tachometer rotor.

18. The apparatus of claim 12, further comprising means for controlling the rotational speed of said gas driven prime mover comprising a source of compressed gas and means for regulating the flow of said compressed gas to said gas driven prime mover.

19. The apparatus of claim 18, further comprising operator control means for controlling the rotational speed of said gas driven prime mover.

20. The apparatus of claim 19, wherein said operator control means comprises a foot pedal which can be pressed by an operator, said operator control means causing said means for controlling the rotational speed of said gas driven prime mover to supply gas to said prime mover.

21. The apparatus of claim 2, further comprising a fiberoptic tachometer, said fiberoptic tachometer comprising:

(a) a tachometer rotor mounted on said prime mover shaft, said tachometer rotor having at least one means for interrupting a light beam thereon;

(b) a pair of fiberoptic cables, one of which shines light through the path through which said at least one means for interrupting a light beam passes, the other one of which carries transmitted pulses from said tachometer rotor; and

(c) means for obtaining a count of said transmitted light pulses and converting said count into revolutions per minute.

22. The apparatus of claim 21, wherein said body includes a slot formed therein for moving said advancer assembly within said body.

23. The apparatus of claim 22, wherein said advancer assembly includes means for attaching an air hose, a fiberoptic cable, and a source of infusate thereto.

24. The apparatus of claim 23, wherein said body has a slot formed therein for attaching said air hose, said fiberoptic cable, and said source of infusate.

25. The apparatus of claim 24, further comprising a lock means for locking the position of said advancer assembly within said body.

26. The apparatus of claim 25, further comprising a fixed front support means and a fixed rear support means within said body, said support means being adapted to define the distal and proximal limits of travel of said advancer assembly.

27. The apparatus of claim 26, wherein said advancer assembly includes tube means surrounding said drive and slidable over fixed tube means attached to said front and rear support means, whereby a continuous, sealed, telescopic tube extends from said advancer assembly to said sheath.

28. The apparatus of claim 24, further comprising means remote from said body for measuring the rotational speed of said gas driven prime mover.

29. The apparatus of claim 28, wherein said means for measuring the rotational speed of said gas driven prime mover comprises:

(a) a light supply means for supplying light through a first fiberoptic cable attached to said advancer assembly;

(b) light detecting means for counting light pulses arriving on a second fiberoptic cable attached to said advancer assembly; and

(c) converting means for converting said count into a measure of revolutions per minute by dividing said count per unit time by the number of reflective areas on said tachometer rotor.

30. The apparatus of claim 24, further comprising means for controlling the rotational speed of said gas driven prime mover comprising a source of compressed gas and means for regulating the flow of said compressed gas to said gas driven prime mover.

31. The apparatus of claim 30, further comprising operator control means for controlling the rotational speed of said gas driven prime mover.

32. The apparatus of claim 31, wherein said operator control means comprises a foot pedal which can be pressed by an operator, said operator control means causing said means for controlling the rotational speed of said gas driven prime mover to supply gas to said prime mover.