Embolectomy catheters and methods for treating stroke and other small vessel thromboembolic disorders

• US 6,511,492 B1
• Filed: 05/01/1998
• Issued: 01/28/2003
• Est. Priority Date: 05/01/1998
• Status: Expired due to Term

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Rosenbluth, Robert F., Cox, Brian J., Greene, George R. Jr.
• Primary Examiner(s): Dawson, Glenn K.
• Application Number:
  US09/071,561
• Time in Patent Office: 1,733 Days
• Field of Search: 606/1, 606/110, 606/113, 606/127, 606/159, 606/167, 606/200
• US Class Current: 606/159
• CPC Class Codes: A61B 17/135 inflatable for measuring blood pressure A61B5/022; inflatable pressure pads A61F5/34
• CPC Class Codes: A61B 17/22032 having inflatable gripping elements balloon catheters A61M25/10
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 2017/22034 for gripping the obstruction or the tissue part from inside
• CPC Class Codes: A61B 2017/22044 with a pointed tip
• CPC Class Codes: A61B 2017/22077 with a part piercing the tissue A61B2017/22044 takes precedence
• CPC Class Codes: A61B 2017/22084 stone- or thrombus-dissolving
• CPC Class Codes: A61B 2017/22094 for crossing total occlusions, i.e. piercing
• CPC Class Codes: A61B 2017/2212 having a closed distal end, e.g. a loop
• CPC Class Codes: A61B 2017/320716 comprising means for preventing embolism by dislodged material
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2002/018 made from tubes or sheets of material, e.g. by etching or laser-cutting
• CPC Class Codes: A61F 2230/008 paraboloidal
• CPC Class Codes: A61F 2230/0091 helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61M 2025/0042 Microcatheters, cannula or the like having outside diameters around 1 mm or less
• CPC Class Codes: A61M 2025/0183 Rapid exchange or monorail catheters

Abstract

Embolectomy catheters, rapid exchange microcatheters, systems and methods for removing obstructive matter (e.g., thrombus, thromboemboli, embolic fragments of atherschlerotic plaque, foreign objects, etc.) from blood vessels. This invention is particularly useable for percutaneous removal of thromboemboli or other obstructive matter from small blood vessels of the brain, during an evolving stroke or period of cerebral ischemia. In some embodiments, the embolectomy catheters of this invention are advanceable over a guidewire which has been pre-inserted through or around the obstructive matter. Also, in some embodiments, the embolectomy catheters include obstructive matter capturing receptacles which are deployable from the catheter after the catheter has been advanced at least partially through the obstructive matter. Such obstructive matter capturing receptacles may include i) at least one proximal strut which are designed to be retractable through a blood clot and ii) a distal matter-receiving portion which is designed to prevent a blood clot from passing therethrough.

Claims

1. An embolectomy catheter device for removing a blood clot or other obstructive matter from a blood vessel, said device comprising:

an elongate flexible catheter body having a proximal end, a distal end, and a guidewire lumen which extends longitudinally through at least a portion thereof, wherein a plurality of member guide passageways extend through the distal end of the catheter; and

an obstructive matter capturing receptacle which is initially disposed in a first stowed configuration which is passable through the obstructive matter, and is subsequently deployable to a second radially expanded configuration, the obstructive matter capturing receptacle comprises a plurality of elongate members which are preformed to generally helical configurations, and which extend through the guide passageways formed in the distal end of the catheter, said elongate members being retractable in a proximal direction through said guide passageways whereby they will assume substantially straight configurations;

said obstructive matter capturing receptacle having a guidewire passageway which extends longitudinally therethrough in alignment with the guidewire lumen of said catheter body, such that the obstructive matter capturing receptacle and the catheter body may be advanced over a previously positioned guidewire, said elongate members being advanceable in a distal direction through said guide passageways such that they will assume their generally helical configurations and will form said clot capturing receptacle.

2. The embolectomy catheter device of claim 1 wherein the obstructive matter capturing receptacle is sufficiently porous to allow blood to flow therethrough, but sufficiently non-porous to prevent a blood clot from passing therethrough.

3. The embolectomy catheter device of claim 2 wherein said obstructive matter capturing receptacle has openings of 100-1000 microns formed therein, to provide a porosity of 25% to 90%.

4. The embolectomy catheter device of claim 1 wherein the obstructive matter capturing receptacle is formed of pre-formed, elastic material which collapses to said first configuration when retracted into the catheter, and expands to said second configuration when advanced out of said catheter.

5. The embolectomy catheter of claim 4 wherein the obstructive matter capturing receptacle is formed of a material which is superelastic at body temperature.

6. The embolectomy catheter of claim 5 wherein the obstructive matter capturing receptacle is formed of a nickel-titanium alloy which is superelastic at body temperature.

7. The embolectomy catheter device of claim 1 further comprising:

a proximal connector formed on the proximal end of the catheter body, said proximal connector having an injection port formed therein to permit radiographic contrast medium to be injected through a lumen of the catheter body while a guidewire is positioned within the guidewire lumen of the catheter body.

8. The embolectomy catheter device of claim 1 wherein distal portions of said elongate members will, when unconstrained, form a distal obstructive matter receiving portion of the receptacle and proximal portions of said elongate members will form struts which extend from the catheter body to the distal obstructive matter receiving portion of the receptacle.

9. The embolectomy catheter device of claim 8 wherein said struts are configured and positioned to pass through a clot when withdrawn therethrough in a proximal direction, but the distal obstructive matter receiving portion of the receptacle is sufficiently dense to prevent that clot from passing therethrough.

10. An over the wire embodiment of the embolectomy catheter of claim 1 wherein the guidewire lumen extends longitudinally through substantially the entire catheter body.

11. The embolectomy catheter device of claim 1 wherein the catheter body is of greater flexibility near its distal end than near its proximal end.

12. The embolectomy catheter device of claim 11 wherein at least a portion of the catheter body between its proximal and distal ends is of gradually increasing flexibility over its entire length.

13. The embolectomy catheter device of claim 11 wherein the catheter body comprises at least two discrete regions of differing flexibility.

14. The embolectomy catheter device of claim 11 wherein the catheter body comprises at least two discrete regions of differing diameter.

15. The embolectomy catheter device of claim 14 wherein said discrete regions of differing diameter are also of differing flexibility.

16. The embolectomy catheter of claim 1 wherein the obstructive matter capturing receptacle and catheter body are constructed so as to be extractable, with the removed obstructive matter, through a percutaneous vascular access tract.

17. A rapid exchange embodiment of the embolectomy catheter of claim 1 wherein the catheter device further comprises a guidewire passage aperture formed in the catheter body a spaced distance proximal to the distal end thereof, and wherein the guidewire lumen of the catheter body extends at least from the guidewire passage aperture to the distal end of the catheter body.

18. The embolectomy catheter device of claim 17 further comprising a guidewire deflector positioned within the guidewire lumen of the catheter body and configured to deflect the proximal end of a guidewire out of the guidewire passage aperture, as the catheter body is advanced in the distal direction over the guidewire.

19. The embolectomy catheter device of claim 18 wherein the guidewire deflector comprises a curved guidewire deflector tube having a proximal end positioned at the guidewire passage aperture and a distal end positioned within the guidewire lumen of the catheter such that the proximal end of the guidewire will be received within the distal end of the curved guidewire deflector tube and will thereafter pass through the curved guidewire deflector tube and out of the guidewire passage aperture.

20. The embolectomy catheter device of claim 19 wherein the distal end of the curved guidewire deflector tube is larger in diameter than the rest of the curved guidewire deflector tube to facilitate entry of the proximal end of the guidewire into the distal end of the curved guidewire deflector tube.

21. The embolectomy catheter device of claim 19 wherein at least one support member is attached to the distal end of the curved guidewire deflector tube to hold the distal end of the curved guidewire deflector tube in a substantially centered position within the guidewire lumen of the catheter.

22. The embolectomy catheter device of claim 19 wherein the guidewire lumen of the catheter body additionally extends through the portion of the catheter body proximal to the guidewire passage aperture and is used for injection of radiographic contrast medium as well as for passage of the guidewire and wherein at least one flow passageway is formed adjacent the distal end of the curved guidewire deflector tube to allow radiographic contrast medium to flow past the curved guidewire deflector tube and out of the distal end of the catheter body.

23. The embolectomy catheter device of claim 1 further comprising a tip member formed on the distal ends of said elongate members, said guidewire lumen of the receptacle extends through said tip member.