Method and device for locating guidewire and treating chronic total occlusions

Abstract

Devices, methods, kits, and methods remove obstructive material from the vasculature and other body lumens. Expansible baskets may be used as cooperating radially expansible shearing members. Helically oriented struts of each basket may wind in a uniform circumferential direction. The struts can be independently flexible, allowing the shearing members to flex axially together. The inner basket may be rotatably driven and may use an axial pump extending proximally from the shearing members and / or a distal penetrator for advancing into an occlusion which inhibits guidewire access. The struts may slide substantially continuously across each other, and may be sufficiently aggressive for highly effective thrombectomy. A rotationally static and axially flexible outer basket may provide a safe, limited atherectomy treatment.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS[0001] The present application claims the benefit of priority from Provisional application Ser. No. 60 / 193,539 filed Mar. 31, 2000 (Attorney Docket No. 19744P-001000US), and from Provisional application Ser. No. 60 / 260,170 filed Jan. 4, 2001 (Attorney Docket No. 19744P-001200), the fall disclosures of which are incorporated herein by reference.[0002] 1. Field of the Invention[0003] The present invention relates generally to medical devices and methods. In one embodiment, the present invention relates to devices and methods for disrupting, collecting, and removing thrombus and / or other occlusive material from blood vessels and other body lumens. In other embodiments, the present invention relates to devices and methods for placement of guidewires, often for subsequent removal of unwanted tissue, thrombus, atheroma, fluid, polyps, cysts or other obstructive matter from natural and artificial body lumens such as blood vessels, grafts, implanted s...

AI Technical Summary

Benefits of technology

[0024] The struts may be helically oriented with a local pitch of the struts varying axially along the struts. The local pitch can increase toward the proximal and distal portions sufficiently to inhibit excessive separation between adjacent struts when the outer shearing member flexes axially. The struts may have protrusions which inhibit sliding of obstructive material axially between cooperating edges of the inner and outer shearing bodies. At least one expansion actuator may extend proximally from the shearing members so that the inner and outer shearing members can be radially expanded in situ. Axial translation of an expansion actuator may selectively radially expand the inner and outer shearing members concurrently.

[0026] It may also be desirable to attach a porous or non-porous coverings or coatings to at least one shearing member, particularly to the outer shearing member. Such a covering or coating may extend between the struts of a shearing member or positioning cage when the shearing member or positioning cage expands, and can be made from PTFE woven material, filter material (metallic or polymeric), braid material (metallic or polymeric), mesh, polymeric coatings, and the like. The coatings can be applied to the outer basket through a dipping process. Alternatively, the coverings may be applied to the outer basket using cyanoacrylate or other adhesives, thread or suturing, welding or bonding, or the like. Such coatings may be disposed along a distal and / or proximal region of the expandable perforate shearing member or positioning cage, and may inhibit embolization of fragmented occlusive material, constrain a treatment fluid or fluid stream, and the like.

Problems solved by technology

The resulting shearing action is sufficiently aggressive for highly effective thrombectomy, while use of a rotationally static and axially flexible outer basket may provide a safe, limited, and controllable atherectomy treatment.

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