INFUSION FILTER AND METHOD FOR PERFORMING THROMBOLYSIS
20230233310 · 2023-07-27
Inventors
Cpc classification
A61M25/0074
HUMAN NECESSITIES
A61F2230/0091
HUMAN NECESSITIES
A61F2250/0067
HUMAN NECESSITIES
A61M25/007
HUMAN NECESSITIES
International classification
Abstract
An infusion filter design combines a fluid infusion device and a blood filtration device that filter blood during a thrombolysis procedure while allowing for complete filter removal on procedure completion. In one embodiment, a wire comprises a proximal, non-infusible length that extends partially outside of the patient and within the vein. The wire further comprises an infusible length distally from the non-infusible length that is extends within the vein so as to be placed at the section of the vein requiring medication. The wire also comprises a distal filter component at a distal end of the wire that is employed to filter the blood in the event that during the period that clot is dissolved it migrates toward the central circulation.
Claims
1. A method for performing venous thrombolysis comprising: deploying a guidewire within a blood vessel from an upstream side of a blood clot so that a distal end of the guidewire reaches a downstream side of the blood clot; inserting a catheter over the guidewire; removing the guidewire while the catheter is in place; deploying an infusion filter through the catheter, the infusion filter comprising: a non-infusible length wire extending from a proximal end of the infusion filter, the non-infusible length comprising a lumen extending therethrough; an infusible length wire extending distally from the non-infusible length wire, the infusible length wire comprising a lumen extending therethrough and a permeable wall; and a filter portion extending from the infusible length wire, the filter portion comprising residual stresses, surface tensions, or both that cause the filter portion to form a predetermined shape when deployed in a blood vessel; positioning the infusion filter such that the infusible length wire is adjacent to the blood clot and the filter portion is disposed downstream from the blood clot; removing the catheter with infusion filter in place; dispensing medication into the blood vessel through the permeable wall for a predetermined treatment period; and removing the infusion filter from the patient.
2. The method of claim 1, wherein the permeable wall comprises a plurality of holes.
3. The method of claim 1, wherein the predetermined shape comprises one of a helix shape, a vortex shape, a nested shape, and a tangled web shape.
4. The method of claim 1, wherein the infusion filter further comprises an outer cover that is disposed over the filter portion and is removable from the filter portion when the filter portion is deployed.
5. The method of claim 1, wherein the infusion filter further comprises a luer lock on a proximal end thereof to convey the medication to the lumen of the non-infusible length wire.
6. The method of claim 1, wherein the filter portion comprises a lumen and a permeable wall.
7. A method for performing venous thrombolysis comprising: deploying a guidewire within a blood vessel from an upstream side of a blood clot so that a distal end of the guidewire reaches a downstream side of the blood clot; inserting a catheter, having a proximal end and a distal end, over the guidewire, the catheter having a non-infusion portion and an infusion portion near the distal end, the infusion portion configured with a permeable wall; removing the guidewire while the catheter is in place; deploying a filter through the catheter, the filter comprising: a filter wire having a proximal end and a distal end; and a filter portion at the distal end of the filter wire, the filter portion comprising residual stresses, surface tensions, or both that cause the filter portion to form a predetermined shape when deployed in a blood vessel; positioning the filter portion adjacent to and downstream from the blood clot; and dispensing medication into the catheter which flows into the blood vessel through the permeable wall.
8. The method of claim 7, wherein the permeable wall comprises a plurality of holes.
9. The method of claim 7, wherein the predetermined shape comprises one of a helix shape, a vortex shape, a nested shape, and a tangled web shape.
10. The method of claim 7, wherein the filter portion further comprises an outer cover that is disposed over the filter portion and is removable from the filter portion when the filter portion is deployed in the blood vessel.
11. The method of claim 7, wherein the catheter further comprises a luer lock on the proximal end to convey the medication into the catheter.
12. The method of claim 7, wherein the infusion portion of the catheter comprises a stopper at the distal end of the catheter to prevent flow of medication out of the distal end of the catheter.
13. A method for performing venous thrombolysis comprising: inserting a catheter having a proximal end and a distal end, into a blood vessel having a blood clot, the catheter having a non-infusion portion and an infusion portion, at or near the distal end, that has a permeable wall; deploying a filter through the catheter, the filter comprising: a filter wire having a proximal end and a distal end; and a filter portion at the distal end of the filter wire, the filter portion comprising residual stresses, surface tensions, or both that cause the filter portion to form a predetermined shape when deployed in the blood vessel from the distal end of the catheter; positioning the filter portion adjacent to and downstream from the blood clot and outside of the catheter to allow the filter portion to form the predetermined shape; and dispensing medication into the catheter which flows through the catheter and into the blood vessel through the permeable wall of the catheter.
14. The method of claim 13, wherein the permeable wall comprises a plurality of holes.
15. The method of claim 13, wherein the predetermined shape comprises one of a helix shape, a vortex shape, a nested shape, and a tangled web shape.
16. The method of claim 13, wherein the filter portion further comprises an outer cover that is disposed over the filter portion and is removable from the filter portion when the filter portion is deployed in the blood vessel.
17. The method of claim 13, wherein the catheter further comprises a luer lock on a proximal end of the catheter to convey the medication to the catheter.
18. The method of claim 13, wherein the infusion portion of the catheter comprises a stopper located at the distal end of the catheter to prevent flow of medication from the distal end of the catheter.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. In the figures, like reference numerals designate corresponding parts throughout the different views.
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DETAILED DESCRIPTION OF EMBODIMENTS
[0062] In the following description, numerous specific details are set forth in order to provide a more thorough description of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without these specific details. In other instances, well-known features have not been described in detail so as not to obscure the invention.
[0063] One of the primary concerns regarding deep vein thrombosis (DVT) is that should the thrombosis (blood clot) dislodge from the original location, the clot may travel to another region of the circulatory system and cause injury and or death to the subject. For example, if a DVT dislodges it may migrate through the heart and eventually re-lodge in the lung of the subject, thus causing a pulmonary embolism (PE) which prevents adequate circulation and respiration, and can cause sudden death. By placing an intravenous filter in the common femoral vein, the blood clot is captured and prevented from migrating to vulnerable regions of the circulatory system. The filter may be placed in any vein or at any location such that the filter can capture a clot prior to causing damage to the patient. The term vein and vessel are used and defined interchangeably herein.
[0064] Referring now to the drawings,
[0065]
[0066]
[0067] As stated above, placement of an IVC filter within the inferior vena cava 300 is expensive, requires special surgical procedures, requires imaging from a radiology or cardiology suite to ensure correct placement with the inferior vena cava, and is a substantially difficult and complicated surgery. In addition, known IVC filters must be placed in a large bore vein, and the placement surgery itself poses a significant risk in patients with conditions that prevent proper blood clotting.
[0068] The vascular filter in the disclosed embodiments has several advantages over known filters. In contrast to the above, the vascular filter of the disclosed embodiments may be placed within one of the common femoral veins 302. In addition, the vascular filter may be placed at any other location in the body which is suited to capture or retain blood clots to prevent the clots from migrating to more critical areas. The vascular filter may be placed “blind” without imaging guidance from an expensive radiology or cardiology suite. Furthermore, the vascular filter may be placed in the common femoral vein 302 at hip level which is an area routinely used for catheter and other line access. Use of this common access area is another advantage in that such use of a commonly accessed area tends to reduce complexity and risk during placement as it is a well-known access area.
[0069] Though placement at hip level has advantages, placement at hip level may not be ideal in all patients and thus the vascular filter may also be placed in other areas. For example, in one embodiment, the filter may be placed in the groin region 306 of the patient. It is contemplated that the vascular filter may be placed where it is best able to capture a dislodged blood clot and that more than one filter may be placed to ensure that any dislodged blood clots are captured. For example, in one embodiment the vascular filter may be placed in both of the common femoral veins 302 should the patient's medical condition require filtration of both legs. In other embodiments, additional vascular filters may be placed as well.
[0070] Placement of the vascular filter begins by accessing a common femoral vein 302. Though the following description describes an embodiment of the present invention where the vascular filter is placed within a common femoral vein 302, the vascular filter may be similarly placed in other veins where dislodged blood clots may be captured as necessary.
[0071]
[0072] Generally, proper access to the common femoral vein 302 may be verified by syringe aspiration (drawing blood from the vein into the body of the syringe) and is visually confirmed by blood return 500 into the syringe. In other embodiments, elements other than a syringe may be utilized including, but not limited to a single hollow large bore needle of which the blood can be seen flowing out of without syringe aspiration.
[0073] As illustrated in
[0074] It is noted that disengagement or removal of the syringe 402 from the needle 400 may occur in various ways and that the syringe is releasably attached to the needle. For example, the syringe 402 may be fitted with a bayonet type of locking mechanism that retains the needle 400 within the end of the syringe. In addition, any other type of mechanism in addition to or other than a bayonet type locking mechanism may be utilized including but not limited to a manufactured threaded coupling system with “male and female” thread components. The locking mechanism may be any type of configuration that releasably retains the needle in the syringe and because these mechanisms are well known in the art they will not be described in detail so as not to obscure the present invention.
[0075] Attachment of the vascular filter dispenser 700 to the needle 400 is illustrated in
[0076] Reference is now made to
[0077] As best illustrated in
[0078] In one or more embodiments, the filter wire 800 has a first and a second end and is preferably fabricated from a suitable material such as titanium, Nitinol, or monofilament strand, to name a few. The filter wire 800 may also be fabricated from a polymer as well. The wire may be similar to known wires commonly used in the medical industry and, in one or more embodiments, may range in diameter from 0.015-0.035 of an inch. Additionally, the filter wire 800 may be treated with a compound that prevents clot formation on the wire such as a Heparin anticoagulation coating. The wire may comprise a mesh form or may be constructed of metal, plastic or a combination thereof or any other material. In addition, the filter wire 800 may have a very flexible tip at its first end to reduce the possibility of damaging the inside wall of a vein when the filter wire is implanted.
[0079] In one embodiment, an important characteristic of the filter wire 800 is that the wire be preformed to have residual stresses and/or surface tensions such that the wire will automatically coil once advanced beyond the delivery needle end 902. For example, the filter wire may be fabricated so that the surface tension along the length of the wire causes the wire to naturally coil unless otherwise constrained. In this way, the filter wire 800 may be housed or stored in one dispenser configuration and upon proper deployment; the filter wire would coil into a predetermined shape. In another embodiment, the filter wire may be preformed to take any various shapes that will achieve the goals set forth herein. For example, the filter wire may be preformed to have a vortex shape (coils of increasing/decreasing diameter) once deployed. Other embodiments may provide filter wire that is preformed to have a nesting or tangled web shape.
[0080] As illustrated in
[0081] In
[0082]
[0083] In the event that a blood clot 1500 is captured by the vascular filter, the clot may be removed in one of several ways. First, the entangled blood clot 1500 may be verified using ultrasound or x-ray techniques. If there is a blood clot 1500, then the blood clot may be dissolved using anticoagulation therapy or any other means. If the blood clot 1500 does not dissolve in a timely manner, the attending physician may decide to perform additional procedures such as thrombectomy or thrombolysis to resolve the blood clot. In some cases, permanent placement of a standard IVC filter may be required where the blood clot does not dissolve.
[0084]
[0085] The vascular filter disclosed herein has several advantages over known IVC filters. The new vascular filter is inexpensive and easily deployed/removed with minimal intrusion to the patient. In contrast, existing vascular filters require a complex and potentially risky deployment procedure which is very expensive, requires a team of medical professionals and the use of an operating room or cardiology suite. Additionally, existing vascular filters require an even more complicated and risky procedure for removal.
[0086] The new vascular filter is placed without the need for complex fluoroscopic guidance (i.e., the new filter may be placed blindly). For example, unlike existing filters that are placed within the inferior vena cava which requires x-ray fluoroscopic guidance for deployment, the new vascular filter may be placed without using any x-ray or imaging equipment.
[0087] The new vascular filter is minimally invasive and can be deployed at the patient's bedside or in an emergency room setting. Correspondingly, removal of the new vascular filter may be performed at a convenient location such as bedside.
[0088] The new vascular filter reduces the risk of complications because the filter is placed in a more conducive location within the patient's body. As disclosed herein, the new vascular filter may be placed in the pelvic or groin region of the patient unlike existing IVC filters which are generally placed in the upper abdomen or thoracic region. As a result, the new vascular filer is placed within one or both of the more accessible common femoral veins and is minimally intrusive for the patient. Another desirable aspect of the new vascular filter is a substantial reduction in recovery time for either deployment or removal of the new filter. In contrast, the existing filters require a substantial recovery time for both deployment and removal.
[0089] As an improvement to the filter and method of use described above, also disclosed is the filter configured as a route for infusion of fluids, gels, or medications through the filter and into the blood stream. The infused material may medicate the entire body or vascular system, or just the area of the filter. As such treatment can be directed to a very direct and focused area of the body or arterial system. As discussed above, the filter may be used to retain clots and as such, while the clot is retained within the filter, medication may be applied or infused through the filter as disclosed below to target the retained clot. This provides the benefit of concentrating the medication to the clot which is particularly useful for application of clot dissolving medication such as, but not limited to, Tissue Pasminogen Activator (TPA—Alteplase). In addition, it is also contemplated that medication may be infused through the filter as described below to prevent clotting of the blood around or onto the filter, or any other type of build-up of material or growth on the filter. This extends the effective life of the filter within the body and increases the ease of removal.
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[0091] The filter wire maybe categorized into a perforated section 1630 which is contained within in the vascular system. The filter wire also includes an un-perforated section 1634 that connects the perforated section 1630 at a distal end and to the attachment hub at the proximal end. The perforated section has one or more openings (shown in
[0092] The filter sections 1630, 1634 includes a passage between an open end at the hub attachment 1620 and the perforations (not shown in
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[0094] As shown generally, the filter includes hub attachment 1620 and the filter wire 1600. A non-perforated section of the filter wire connects the perforated filter section to the hub assemble. The filter may be made from any type material that is configured to perform as described herein.
[0095] A fluid chamber 1640 configured to connect to the hub assembly, which in this embodiment is a luer lock 1644. The fluid chamber 1640 contains medication or other material which is provided to the filter 1600 and ultimately to the patient. The fluid chamber may be part of a syringe, drip-line, infusion pump or medication administration device or any other element configured to store and connect to a hub assembly. The fluid chamber 1640 may permanently connect to the filter or may be selectively connectable and removable to apply medication or other material to the filter.
[0096] Configured to mate with or connect to the fluid chamber 1640 is a luer lock 1644 having a first end 1648 with an opening configured to mate with the external shape of the fluid chamber 1640, in this embodiment a tapered end. The hub attachment 1620 assembly is an addition to the prior art as it allows wire placement, such as for example, through a needle with the eventual needle removal. Once the entry needle is removed the hub assembly 1620 can be applied to the portion of the filter that is external to the body for infusion.
[0097] The luer lock 1644 is generally known in the art and not describe in detail herein. As shown the luer lock 1644 has an internal passageway or lumen from the first end 1648 to a second end 1652. In the second end 1652 is an opening 1656 configured in size and shape to accept a proximal end 1660 of the non-perforated section 1644 filter wire. The opening extends toward the proximal end of the luer lock 1644 to a establish fluid (or there material state) passageway with the fluid chamber 1640. Through this fluid passageway medication or other material may be provided to the filter wire 1600. The medication or other material may be pressurized in the fluid chamber 1640 to establish flow into the lower pressure filter wire. The pressure may be established by a syringe or gravity, or any other force to move the medication or other material from the chamber 1640 to the filter wire.
[0098] The luer lock 1644 also includes an outer ring 1664 with internal threaded which rotationally interact with an externally threaded inner frame 1668 of the luer lock. Through rotational movement of the outer ring 1664 relative to the inner frame 1668 the outer ring moves in the linear direction between the proximal end 1648 and the distal end 1652.
[0099] The movement of the outer ring 1664 relative to the inner frame 1668 crushes an compression element 1670 that when crushed closes the passage between the chamber 1640 and the internal passageway in the filter 1600. The compression element 1670 may comprise any material capable of performing as described herein. The compression element 1670 is a known structure in the luer lock 1646 and it may also be known to pinch or otherwise close the flow of medication or other material into the filter 1600.
[0100] In one configuration the non-perforated section 1634 of the filter in contact with the compression element 1670 may comprise a different material or configuration than the portion of the filter not in contact with the compression element. For example, the non-perforated section 1634 of the filter in contact with the compression element 1670 may be flexible and resilient to return to shape after opening, while the perforated section 1630 may comprise a more stiff material capable of functioning as described above as a filter in a vascular environment.
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[0102] Also shown in
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[0104] This current improvement allows the place filter to be a route of infusion for fluids and/or medication. The enhanced filter with infusion capabilities can therefore aid in patient care as an extra source of venous access, provides an additional means to protect the filter itself from developing blood clots and potentially will provide a means of breaking up or dissolving the trapped clot via infusion of clot dissolving medications including but not limited to Tissue Plasminoge Activater (TPA) and any other medication now existing or develop in the future.
[0105] In summary, once the filter has been placed medication can be infused directly into the blood stream via the inner lumen and multiple infusion pores (openings) located on the intravenous portion of the filter wire. In order to channel fluid through the inner lumen of the filter coil a custom coupling apparatus is provided to attach to a syringe or other device configured to present the medication into the inner passage of the filter wire. The coupler, such as hub assembly, allows for the filter wire with the open inner lumen to be put into fluid communication with a standard IV drip system or other medication administration mechanism via a luer lock connection (hub assembly). Within the coupler is a compression seal (4). When the two coupler bodies are threaded together the compression seal is deformed thus creating a fluid tight seal around the filter wire. Once a seal is made the coupler can be connected to an IV line allowing fluid to pass through the filter wire and infuse into the patient's blood stream.
[0106] It is further contemplated that various coatings can be added to the surface of the filter to enhance its biocompatibility or prevent/inhibit growth or development of unwanted surface tissue by the body on the filter. An example is an antithrombogenic antiplatelet coating or material to prevent development thrombi in vitro. This may further prevent or reduce development of clots or scar tissue development on the vascular filter.
[0107] The above-described vascular filters may also be inserted and removed by other methods. In
[0108] In addition and in reference to
[0109] With the catheter 2510 in place, the filter may be inserted in a manner similar as explained with reference to
[0110] In
[0111] Removal of the filter is shown in
[0112] Further modifications may be made within the scope of the invention. For example, as shown in
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[0116] Returning to
[0117] On the proximal end of the filter 3410, a luer lock type adaptor 3518 is employed that can be attached to a syringe or medical tubing for medication infusion. The luer lock adapter may be either prefixed to the wire or may be an attachment that is attached to the infusion wire. For example, the infusion wire may be advanced into the vessel to the desired location and then the luer lock attached to add an infusing capability.
[0118] As shown in
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[0120] As shown in
[0121] As shown in
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[0123] In step 3906, an infusion filter, such as the one described above, is deployed through the catheter. The infusion filter is positioned so that the filter portion of the infusion filter is deployed downstream in the blood vessel from the clot. Once the infusion filter is in position, the catheter may be removed as described in step 3908. The infusion filter is deployed such that the infusion portion aligns with the blood clot in the patient's blood vessel. When the infusion filter is in place, medication or other fluid may be pumped into the infusion filter and forced through the infusion portion of the filter in step 3910.
[0124] For the exemplary thrombolysis method described here, a thrombolytic agent such as those known in the art is fed through the infusion filter into the infusion portion to treat the blood clot by dissolving the blood clot. The infusion filter allows the thrombolytic agent to be directed along the length of the blood clot to help dissolve the blood clot. Furthermore, with the filter portion being disposed downstream from the blood clot, any pieces of the dissolving clot that might break away are filtered and prevented from traveling to other areas of the body where they might cause significant injury or death, such as via a pulmonary embolism. Pieces of the clot caught in the filter may then be gradually dissolved from the medication dispensed through the infusion portion. In some embodiments, the filter portion may also be permeable as described above such that the thrombolytic agent is dispense directly to any clot pieces caught in the filter.
[0125] The fluid is dispensed through the infusion filter for a period of time as prescribed by the medical professional. For example, the treatment may last two days. In step 3912, the infusion filter may be removed once the treatment is complete. The infusion filter is removed similar to the removal of the filters described above. The filter portion of the infusion filter is designed with pitch angles and materials such that the filter can be pulled back out through the incision.
[0126] The infusion filter and method for performing thrombolysis described above have a number of advantages. First, as compared to prior systems where a filter is deployed by a separate procedure, usually by accessing the jugular vein and guiding the filter through the body to be deployed on the downstream side of the clot in the interior vena cava, the present embodiments allow the filter to be easily placed from an access point upstream from the clot. Further, the infusion filter dispenses the medication, such as the thrombolytic agent, directly at the site of and throughout the length of the blood clot. This allows a total amount of medication delivered to dissolve the clot to be decreased. When the amount of medication is decreased, the safety of the procedure is increased because the risk for the thrombolytic agent to cause damage elsewhere (such creating internal bleeding) is decreased. The safety is also increased due to effective filtering of the vein downstream from the clot. When the clot dissolves from the thrombolytic agent, any large pieces of the clot are filtered and dissolved rather than entering the bloodstream and possibly resulting in a pulmonary embolism or the like. Finally, when the treatment is complete, the filter may be immediately removed without a separate complicated procedure to retrieve the filter.
[0127] Other variations of the above described method may also be used. For example, instead of the infusion filter, a filter and infusion catheter may also be used, such as the ones described with reference to
[0128] While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of this invention. In addition, the various features, elements, and embodiments described herein may be claimed or combined in any configuration or arrangement.