METHOD AND APPARATUS FOR CENTERING A MICROCATHETER WITHIN A VASCULATURE

• US 20140277008A1
• Filed: 10/22/2013
• Published: 09/18/2014
• Est. Priority Date: 06/26/2007
• Status: Active Grant

• Current Assignee: Roxwood Medical, Inc. (Boston Scientific Corporation)
• Original Assignee: Roxwood Medical, Inc. (Boston Scientific Corporation)
• Inventors: Taber, Mark, Yang, Mark C., FARHANGNIA, MEHRDAD
• Granted Patent: US 9,358,037 B2
• Time in Patent Office: Days
• US Class Current: 606/159
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61M 2025/0042 Microcatheters, cannula or the like having outside diameters around 1 mm or less
• CPC Class Codes: A61M 2025/0046 Coatings for improving slidability
• CPC Class Codes: A61M 2025/0293 Catheter, guide wire or the like with means for holding, centering, anchoring or frictionally engaging the device within an artificial lumen, e.g. tube natural lumen, e.g. vessels A61M25/04
• CPC Class Codes: A61M 2025/0681 Systems with catheter and outer tubing, e.g. sheath, sleeve or guide tube
• CPC Class Codes: A61M 25/0068 Static characteristics of the catheter tip, e.g. shape, atraumatic tip, curved tip or tip structure
• CPC Class Codes: A61M 25/0074 Dynamic characteristics of the catheter tip, e.g. openable, closable, expandable or deformable
• CPC Class Codes: A61M 25/008 Strength or flexibility characteristics of the catheter tip
• CPC Class Codes: A61M 25/04 in the body, e.g. expansible A61M25/10, A61M16/0488 take precedence

Abstract

The invention is directed to methods and apparatus for centering a microcatheter within a vasculature. In one aspect, the methods and apparatus can be used to support centering and to facilitate a guidewire to cross through a chronic total occlusion. In one embodiment, the catheter apparatus includes: a microcatheter having a lumen, a distal opening and a distal end; one or more guidewires for passing through the lumen of the microcatheter; an inner shaft having a lumen, a distal opening and a distal end for passing the inner shaft over the microcatheter; an outer shaft having a lumen, a distal opening and a distal end for passing the outer shaft over the inner shaft; and a self-expandable scaffold structure disposed towards the distal end of the inner shaft. The self-expandable scaffold structure is preferably non-occluding thereby allowing blood to flow through the scaffold. Preferably, the inner shaft and microcatheter are capable of being independently operable.

Claims

1. A catheter apparatus comprising:

a hollow shaft with a distal end and a proximal end, and

a non-occluding self-expandable scaffold having a central longitudinal axis, the self-expandable scaffold being disposed at the distal end of the catheter, wherein a portion of the distal end of the catheter is disposed at least in part inside the self-expandable scaffold,

wherein the distal end is slidable along the shaft, and

wherein the scaffold is configured to be coupled to the distal end of the catheter, wherein at least a portion of the distal end of the catheter is disposed substantially along the central axis of the self-expandable scaffold structure.

2. The catheter apparatus of claim 1, further comprising a sheath for sliding over the hollow shaft.

3. The catheter apparatus of claim 1, further comprising a microcatheter having a lumen, a distal opening, and a distal end.

4. The catheter apparatus of claim 3, wherein the inner shaft and microcatheter are capable of being independently operable.

5. The catheter apparatus of claim 1, further comprising one or more guidewires for passing through the lumen of the microcatheter.

6. The catheter apparatus of claim 5, wherein the microcatheter is more rigid and less flexible than the one or more guidewires.

7. The catheter apparatus of claim 1, wherein the self-expandable scaffold comprises loops which project inwardly from the cylindrical plane of the scaffold to the central longitudinal axis of the self-expandable scaffold structure.

8. The catheter apparatus of claim 7, wherein the loops position the shaft approximately along the central longitudinal axis of the self-expandable scaffold structure.

9. The catheter apparatus of claim 1, wherein the self-expandable scaffold comprises nitinol.

10. The catheter apparatus of claim 1, wherein the self-expandable scaffold comprises a loop network at the distal end of the scaffold.

11. The catheter apparatus of claim 3, wherein the sheath and shaft are flexible.

12. The catheter apparatus of claim 1, wherein the distal end of the shaft is hydrophilic.

13. The catheter apparatus of claim 3, wherein the distal end of the sheath comprises a hydrophilic coating.

14. The catheter apparatus of claim 2, wherein the distal end of the microcatheter is tapered.

15. The catheter apparatus of claim 2, wherein the microcatheter is removable or highly flexible.

16. The catheter apparatus of claim 1, further comprising a handle body.

17. A method of centering a microcatheter in vessel comprising:

inserting a microcatheter into vessel, wherein the microcatheter comprises

a hollow shaft with a distal end and a proximal end,

a non-occluding self-expandable scaffold having a central longitudinal axis, the self-expandable scaffold being disposed at the distal end of the catheter, wherein a portion of the distal end of the catheter is disposed at least in part inside the self-expandable scaffold, and

a sheath

wherein the distal end is slidable along the shaft,

wherein the scaffold is configured to be coupled to the distal end of the catheter, wherein at least a portion of the distal end of the catheter is disposed substantially along the central axis of the self-expandable scaffold structure,

wherein the hollow shaft is covered by the sheath; and

withdrawing the sheath to expand the self-expandable scaffold structure whereby expansion of the scaffold centers the microcatheter along the central longitudinal axis of the scaffold thereby centering the microcatheter in the vessel.

18. The method of claim 17 further comprising inserting a guidewire through the microcatheter.

19. The method of claim 17, wherein the vessel has a chronic occlusion and wherein the method further comprises advancing the microcatheter in contact with the chronic occlusion.

20. The method of claim 17, wherein the self-expandable scaffold comprises loops which project inwardly from the cylindrical plane of the scaffold to the central longitudinal axis of the self-expandable scaffold structure.

21. The method of claim 17, wherein the loops position the shaft approximately along the central longitudinal axis of the self-expandable scaffold structure.