RETRIEVAL SYSTEMS AND METHODS FOR USE THEREOF

• US 20090299393A1
• Filed: 12/26/2008
• Published: 12/03/2009
• Est. Priority Date: 12/26/2007
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Lazarus Effect, Inc. (Medtronic Plc)
• Inventors: FOLLMER, Brett, AGUILAR, Julio, MARTIN, Brian B., DIECK, Martin S.
• Granted Patent: US 8,545,526 B2
• Time in Patent Office: Days
• US Class Current: 606/159
• 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 2017/22094 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 2017/2215 having an open distal end

Abstract

The devices and methods described herein relate to improved structures for removing obstructions from body lumens. Such devices have applicability in through-out the body, including clearing of blockages within the vasculature, by addressing the frictional resistance on the obstruction prior to attempting to translate and/or mobilize the obstruction within the body lumen

Claims

1. A medical device for removing an obstruction from a blood vessel, the medical device comprising:

a main bundle comprising a group of wires having a first end and a second end;

a capturing portion formed by the group of wires and having a translating surface adjacent to a capturing surface, the translating surface having an open proximal end and the capturing surface having a permeable distal end;

where the capturing portion is formed from the group of wires such that the group of wires diverges from the second end of the main bundle to form the permeable distal end, the group of wires extend back in a proximal direction to form the capturing surface, the translating surface, and open proximal end about the main bundle; and

where the translating surface and capturing surface are configured so that a translating surface axial strength is greater than a capturing surface axial strength, wherein application of a tensile force on the main bundle causes axial compression of the capturing surface without causing axial compression and deformation of the translating surface sufficient to deform the translating surface as the capturing portion engages the obstruction.

2. The medical device of claim 1, where the capturing portion is formed such that articulation of the capturing portion relative to the main bundle does not cause the open proximal end to reduce in size.

3. The medical device of claim 1, where the capturing surface is configured to generate a spring force against the translating surface when a proximal force applied by the main bundle of wires compresses the capturing surface against the translating surface when encountering resistance from the obstruction, where the capturing surface is configured to have a sufficient axial stiffness to direct the spring force and proximal force to the open proximal end as the open proximal end engages the obstruction where the capturing surface is also sufficiently flexible to conform to a shape of the vessel.

4. The medical device of claim 1, where the capturing section is configured so that when the open proximal end of the translating section engages resistance equal to or greater than a threshold force, proximal movement of the main bundle inverts the capturing section within the translating section and reduces a size of the capturing section.

5. The medical device of claim 4, where the capturing section and traversing section are configured to invert upon continued proximal movement of the main bundle such that the traversing surface moves distally to the capturing surface.

6. The medical device of claim 1, where the main bundle is joined to a proximal bundle, where the proximal bundle comprises a stiffness greater than the main bundle and where the main bundle extends for a pre-determined distance from the permeable distal end to allow navigation of a distal portion of the medical device within the cerebral vasculature.

7. The medical device of claim 6, where the pre-determined distance is at least 20 cm.

8. The medical device of claim 1, where the capturing surface has an increased frictional resistance as compared to the translating surface, such that the capturing surface engages the obstruction for removal of the obstruction.

9. The medical device of claim 1, where the open proximal end further comprises a plurality of flanges extending from the translating surface.

10. The medical device of claim 9, where the flanges extend radially away from an axis of the capturing portion.

11. The medical device of claim 1, where the capturing portion is self-expandable.

12. The medical device of claim 1, where at least a portion of the capturing surface comprises a structure selected from the group consisting of a basket, a filter, a bag, a coil, a helical wire structure, a mesh, a single wound wire, and a plurality of crossing wires or a combination thereof.

13. The medical device of claim 1, where the main bundle of wires includes at least a first wire and a second wire where the first and second wire each have different characteristics.

14. The medical device of claim 13, where the characteristics are selected from a group consisting of material, cross-sectional shape, and cross-sectional size.

15. The medical device of claim 1, where the main bundle of wires includes at least one shape memory alloy wire.

16. The medical device of claim 1, where the main bundle of wires includes at least one wire selected from the group consisting of a superelastic wire, a polymeric wire, or a metal alloy.

17. The medical device of claim 16, where the metal alloy comprises an alloy selected from the group consisting of stainless steel, titanium, platinum, gold, iridium, tantalum, nitinol, and combinations thereof.

18. The medical device of claim 1, further comprising at least one radiopaque material located on the capturing portion.

19. The medical device of claim 1, where the individual wires in the group of wires each comprise a bundle of smaller wires.

20. The medical device of claim 1, where the individual wire comprises a super-elastic outer shell and an inner core of a radiopaque material.

21. The medical device of claim 20, where the inner core comprises a material selected from a group consisting of platinum, iridium, gold, and tantalum.

22. The medical device of claim 1, where the capturing portion is jointless.

23. The medical device of claim 1, where at least one of the wires from the main bundle returns to the main bundle after forming at least a part of the capturing portion.

24. The medical device of claim 1, where each of the wires from the main bundle returns to the main bundle after forming a part of the capturing portion.

25. The medical device of claim 1, where the main bundle is surrounded by a coil or coiled wire.

26. A retrieval device for removing an obstruction from a body lumen, the retrieval device comprising:

at least one leading wire;

a retrieval body comprising a translating section adjacent to a capturing section, the translating section having an open proximal end and the capturing section having a permeable distal end, where the leading wire extends to a portion of the capturing section to permit articulation of the open proximal end relative to the leading wire; and

where the translating section and capturing section are configured so that a translating section axial strength is greater than a capturing section axial strength, wherein application of a tensile force on the leading wire causes axial compression of the capturing surface without causing axial deformation of the translating surface when the retrieval body engages the obstruction.

27-64. -64. (canceled)

65. A method of removing an obstruction from a blood vessel, the method comprising:

advancing a catheter distal to the obstruction;

deploying a first capturing portion distal of the obstruction, where the first capturing portion comprises a translating surface and a capturing surface, the translating surface having an open proximal end and the capturing surface having a permeable distal end, and at least one leading wire affixed to the capturing surface and extending through the capturing portion and through the catheter, where the translating surface and capturing surface are configured so that a translating surface axial strength is greater than that of a capturing surface axial strength;

proximally moving the leading wire to compress the capturing surface without compressing the translating surface sufficient to cause axial deformation of the translating surface such that the translating surface gradually advances over the obstruction; and

removing the obstruction and first capturing portion from the blood vessel.

66-76. -76. (canceled)

77. A reentry device for withdrawing an object into a distal end of a sheath, the reentry device comprising:

a elongate member having a distal portion and a lumen extending therethrough; and

a plurality of first tines arranged circumferentially at the distal portion, the plurality of first tines each having a distal end forming a first discontinuous funnel where the distal end of each first tine is spaced from the distal end of an adjacent first tine, wherein the first discontinuous funnel is collapsible upon withdrawal into the distal end of the sheath.

78-85. -85. (canceled)

86. A reentry device for withdrawing an object into a distal end of a sheath, the reentry device comprising:

an elongate member having a distal portion and a lumen extending therethrough, the elongate member sized to slidably fit within the sheath;

a first slotted funnel comprising a plurality of first tines each having free ends discontinuous with free ends of adjacent first tines, where the first slotted funnel is collapsible upon withdrawal into the distal end of the sheath; and

a second funnel located proximal to the free ends of the first tines.

87-93. -93. (canceled)

94. A retrieval system for withdrawing an object into a distal end of a sheath, the retrieval system comprising:

an elongate member having a distal portion and a lumen extending therethrough;

a flexible layer having a portion affixed to the elongate member, where a first end of the flexible layer is configured to form a funnel at the distal portion of the elongate member;

a retrieval device advanceable through the elongate member for engaging the object, where proximal movement of the retrieval device into the flexible causes the flexible layer to engage the retrieval device to assist the retrieval device securing the object to the sheath.

95-106. -106. (canceled)

107. A system for removing a object within a body, the system device comprising:

a sheath having a sheath distal end and a sheath lumen extending therethrough;

a reentry device slidably located in the sheath lumen and being advanceable out of the sheath distal end, the reentry device comprising an elongate member having a first slotted funnel and a second slotted funnel, the elongate member having a distal portion and a lumen extending therethrough and being sized to slidably fit within the sheath,

the first slotted funnel and the second slotted funnel each respectively comprising a plurality of first and second tines, each of the tines having a free end discontinuous with the free ends of an adjacent tines, where a distal end of the second slotted funnel is proximal to a distal end of the first slotted funnel and where the first and second tines are rotationally offset such that upon withdrawal into the sheath, the second tines cover a portion off a space between adjacent first tines.

108-114. -114. (canceled)