Reversible Vascular Filter Devices and Methods for Using Same

Abstract

The present invention provides, in one embodiment, a vascular filter device for capturing dislodged blood clots within a vessel. The vascular filter device includes an expandable framework for securing the device within a vessel. The device also a pathway extending through the framework. The device further includes at least one filter in alignment with the pathway for capturing dislodged clots or emboli. In an embodiment, the filter can be given form by a material that can be easily eliminated in situ to permit reestablishment of the pathway.

Description

RELATED APPLICATIONS[0001]The present application claims priority to and benefits of Provisional Application No. 61 / 289,508 filed Dec. 23, 2009, Provisional Application No. 61 / 295,457 filed Jan. 15, 2010, Provisional Application No. 61 / 304,155 filed Feb. 12, 2010, and Provisional Application No. 61 / 314,816 filed Mar. 17, 2010, the disclosures of all of which applications are incorporated herein by reference in their entirety.TECHNICAL FIELD[0002]This invention relates generally to intravascular devices and more particularly to filter devices implantable within the vena cava for capturing dislodged clots or debris.BACKGROUND ART[0003]Vena caval filters can be utilized in conjunction with anti-coagulants and thrombolytic agents to prevent pulmonary embolism and other vascular diseases from occurring within the body. These devices are generally implanted within a vessel, such as the inferior vena cava, to capture dislodged blood clots (emboli) contained in the blood stream. If a blood ...

AI Technical Summary

Benefits of technology

[0010]The present invention provides, in one embodiment, a bi-directional filter device for capturing undesirable materials. The filter device includes an expandable framework for secured placement of the device against a wall of a vessel. In certain embodiments, the framework can include an attachment mechanism to enhance secured placement of the device against the wall of the vessel. The filter device can also include a pathway extending through the expandable framework. In an embodiment, opposing filters may be situated within the pathway, each defined by a plurality of malleable legs capable of being moved by an external force between a position where the plurality of legs are substantially against the framework and a position where the plurality of legs approximate a substantially conical configuration. In one embodiment, the legs of the opposing filters, when approximating the substantially conical configuration, can act to capture undesirable materials flowing through the vessel. The legs of the opposing filters can also be sufficiently spaced apart to capture undesirable materials of a predetermined size. In addition, the legs of one filter can be offset from the legs of the opposing filter, so that should an undesirable material flowing through the framework escapes the legs of one filter, that escaping undesirable material can be captured by the legs of the opposing filter. In various embodiments, the legs of the opposing filters may be designed to direct the undesirable materials captured thereon along a predetermined path. The legs of the opposing filters can also be designed such that where undesirable materials are on the legs of both opposing filters, a fluid pathway still exists through the pat

Problems solved by technology

Deployment of the Greenfield filter often occurs in a tilted fashion, which decreases clot capture ability of the filter.

Thus, continued use of the Greenfield filter in the vessel may lead to accumulation of clots near the apex of the filter, and may further block and interrupt blood flow near the center of the vessel.

As such, leaving an implantable filter in place for an extended period of time may lead to complications, including inferior vena cava thrombosis, deep venous thrombosis, filter migration, and vena cava perforation.

Removal of the filter from the vena cava, however, is met with certain hurdles.

For example, some of these filters may not be easily removable from a patient due to fibrous in-growth into the filter.

Another hurdle to removing a filter from the vena cava results from conventional vena caval filters becoming off-centered or tilted with respect to the hub of the filter as well as the longitudinal axis of the vessel within which the filter is situated.

Removal of an off-centered or tilted filter can be difficult as the barbs or hooks securing the filter in place can dig further into the vessel walls and act to injure or damage the vessel during removal.

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