Patent ID: 12232946

DETAILED DESCRIPTION OF EMBODIMENTS

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.

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.

Referring now to the drawings,FIG.1illustrates a typical DVT where the common femoral vein100has a blood clot102lodged therein. As the blood clot102is formed there is reduced blood flow through the common femoral vein100because the blood clot begins to obstruct the fluid pathway. The reduced blood flow produces an environment that facilitates clot formation. In particular, as the blood flow is reduced, blood begins to coagulate in the chambers of the vascular valves104, and, as a result, the blood clot102increases in size.

FIG.2illustrates a known inferior vena cava vascular filter that is surgically implanted into the patient's upper abdomen. This inferior vena cava filter (IVC filter)200is commonly deployed using a large bore catheter and access to a large bore vein such as the inferior vena cava. The IVC filter200has a first end202and a second end204where the second end comprises a plurality of individual wire components206. In the proximity diagram ofFIG.2, an IVC filter200is shown within the inferior vena cava at location208in the upper abdomen of a patient.

FIG.3illustrates the inferior vena cava300and two common femoral veins302branching off the inferior vena cava. In the known use of intravenous filters such as the IVC filter discussed above, it is common to place the IVC filter within the inferior vena cava300at location304in the upper abdomen.

As stated above, placement of an IVC filter within the inferior vena cava300is 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.

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 veins302. 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 vein302at 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.

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 region306of 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 veins302should the patient's medical condition require filtration of both legs. In other embodiments, additional vascular filters may be placed as well.

Placement of the vascular filter begins by accessing a common femoral vein302. Though the following description describes an embodiment of the present invention where the vascular filter is placed within a common femoral vein302, the vascular filter may be similarly placed in other veins where dislodged blood clots may be captured as necessary.

FIGS.4and5illustrate a common femoral vein302accessed by a dispensing needle400and syringe402assembly. In one or more embodiments, the needle400has a first or delivery end through which a vascular filter is implanted in a patient, and a second or coupling end at which a syringe or filter dispenser may be attached. Notably, the coupling end in one or more embodiments may be configured to permit releasable attachment of the needle400as described further below.

Generally, proper access to the common femoral vein302may be verified by syringe aspiration (drawing blood from the vein into the body of the syringe) and is visually confirmed by blood return500into 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.

As illustrated inFIG.6, the syringe402may be disengaged or removed from the needle400without removing the needle from the common femoral vein302. In one or more embodiments, proper access to the common femoral vein302may be confirmed prior to disengaging the syringe402by inspecting the syringe for blood return. Such blood return confirms that the needle400is within a vein.

It is noted that disengagement or removal of the syringe402from the needle400may occur in various ways and that the syringe is releasably attached to the needle. For example, the syringe402may be fitted with a bayonet type of locking mechanism that retains the needle400within 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.

Attachment of the vascular filter dispenser700to the needle400is illustrated inFIG.7. In one embodiment, the vascular filter dispenser700is a spool device that is configured to house and dispense filter wire housed within the dispenser. The vascular filter dispenser700is fitted with a guide tube702that facilitates the deployment of the filter wire from the dispenser through the needle400and into the common femoral vein302. It is contemplated that the end of the guide tube702be sized for operative insertion into the inner diameter of the needle400. The guide tube702provides a smooth transition for the filter wire during the deployment process as the wire leaves the filter dispenser700and enters the needle400. In some embodiments, filter means other than a wire may be utilized such as but not limited to monofilament strand or other materials with reformable properties. These structures may be pre-formed or shaped and/or configured at the time of use.

Reference is now made toFIGS.8through11individually and in combination for illustrating the deployment of the vascular filter. As shown inFIG.8, a needle400and a vascular filter dispenser700are coupled together, and the filter dispenser is actuated such that the filter wire800is fed from the dispenser through the needle and into the common femoral vein302. In one embodiment, the filter dispenser700is actuated by a rotational movement of the dispenser so that the filter wire800is un-coiled and fed down the guide tube702and into the needle400. It is contemplated that the filter dispenser700may comprise a user-rotatable wheel or knob in one or more embodiments. When rotated, the knob un-coils the filter wire800and feeds the wire800down the guide tube702. The knob may un-coil the filter wire800through physical contact with the filter wire. However, it is contemplated that there may be an attached reel which is actuated by rotational movement of knob. Other embodiments of the filter dispenser700are contemplated such as a linear dispenser by which the filter wire is translated down the length of the dispenser and into the needle.

As best illustrated inFIG.9, as the filter wire800traverses down the needle400it remains substantially straight. However, when the filter wire800exits the end902of the needle400, the filter wire begins to form a coil900within the common femoral vein302. The filter wire coils due to residual stresses of the wire and the preformed shape memory imparted into the wire during the manufacturing process.

In one or more embodiments, the filter wire800has 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 wire800may 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 wire800may 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 wire800may 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.

In one embodiment, an important characteristic of the filter wire800is 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 end902. 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 wire800may 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.

As illustrated inFIGS.10and11, as the filter wire800is advanced into the common femoral vein302, the coil900becomes larger and longer such that a substantial coil of wire is formed within the vein. As a result, the coil900becomes a partial flow restriction within the common femoral vein302capable of capturing and retaining a blood clot therein.

InFIG.12, the filter wire800has been deployed and the filter dispenser700and delivery needle400are retracted from the subject's common femoral vein302. As the dispenser700and needle400are removed, a portion1200of the filter wire800may be left protruding from the subject's skin surface1202so that it may be secured to a fixation device1300(FIG.13) to prevent the filter wire800from moving within the vein. As illustrated inFIGS.13and14, a portion1200of the filter wire800is intentionally left protruding from the subject's skin surface1202so that it may be looped and subsequently attached to a fixation device1300. The fixation device1300is then secured using a medical dressing to the subject's skin1202and may cover the filter wire's exit. It is contemplated that types of fixation devices1300other than those illustrated in the figures may be used, and that in other embodiments the protruding portion1200of the filter wire800may be attached in other ways such as by tying or adhering the filter wire to the fixation device.

FIGS.15and16illustrate a blood clot1500approaching and being captured by the deployed vascular filter. As the blood clot1500migrates down the vein, it will encounter and preferably become trapped by the coil900of the vascular filter. As illustrated inFIG.16, the blood clot1500will become lodged or entangled with the vascular filter's coils, and, in this way, the clot is prevented from entering other regions of the subject's circulatory system.

In the event that a blood clot1500is captured by the vascular filter, the clot may be removed in one of several ways. First, the entangled blood clot1500may be verified using ultrasound or x-ray techniques. If there is a blood clot1500, then the blood clot may be dissolved using anticoagulation therapy or any other means. If the blood clot1500does 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.

FIGS.17through19illustrate removal of the vascular filter. InFIG.17, the fixation device1300and associated dressing are removed from the patient's skin surface1202. Next, the protruding portion1200of the filter wire800is drawn away from the patient. As the filter wire800is drawn out of the patient, the filter coil900unwinds and/or unravels as illustrated inFIGS.18A through18D. A hydrophilic coating or hydrophilic filter wires800may be used, in one or more embodiments, to facilitate removal of the filter coil900. Once the filter wire800is completely extracted from the patient as shown inFIG.19, the vascular filter has been successfully removed and may be discarded.

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.

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.

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.

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.

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.

FIG.20illustrates an infusible filter and associated hub assembly. As discussed above, the filter1600is located within the vascular system, such as vein1604located below the surface of the skin1608. A hub attachment1620connects to the externally located end1624of the filter1600. The base function of the filter1600operates as described above and in connection withFIGS.1-19. In this embodiment the filter1600including the externally located end1624includes an inner passageway that is configured to conduct medication or other material such as a liquid or gel. The passageway may comprise a lumen.

The filter wire maybe categorized into a perforated section1630which is contained within in the vascular system. The filter wire also includes an un-perforated section1634that connects the perforated section1630at a distal end and to the attachment hub at the proximal end. The perforated section has one or more openings (shown inFIG.21) through which the medication or other material may exit the filter. The number and shape of the openings may be varied to meet the requirements of the filter, medication, and particular medical application.

The filter sections1630,1634includes a passage between an open end at the hub attachment1620and the perforations (not shown inFIG.20) for the movement of the medication or other material into the filter, through the filter, and out of the perforations. The hub attachment1620, the structure of which is discussed below in connection withFIG.21, serves several purposes and functions. The hub attachments provides an access port to the internal passage within the filter sections1630,1634to thereby provide an input port for the medication or other material. The hub attachment1620also provides a clamping or compression element to open and close the opening into the internal passage of the filter. This controls the flow of medication or other material into and output of the internal passage. The hub attachment1620also provides an attachment point and structure to attach a syringe, drip line, medication storage/dispensing device infusion pump, or any other element configured to deliver medication or other material to the filter.

FIG.21Aillustrates a more detailed view of the infusible filter and hub assembly including a close up of the filter wire with infusing mechanism. This is but one possible configuration of the filter and hub assembly. It is contemplated that in other embodiments other configurations may be realized without departing from the claims that follow. For example, different medical applications may require that the disclosed and claimed device interface with other medical devices and as such modifications may be made to the device shown without departing from the scope of the invention and claims.

As shown generally, the filter includes hub attachment1620and the filter wire1600. 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.

A fluid chamber1640configured to connect to the hub assembly, which in this embodiment is a luer lock1644. The fluid chamber1640contains medication or other material which is provided to the filter1600and 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 chamber1640may permanently connect to the filter or may be selectively connectable and removable to apply medication or other material to the filter.

Configured to mate with or connect to the fluid chamber1640is a luer lock1644having a first end1648with an opening configured to mate with the external shape of the fluid chamber1640, in this embodiment a tapered end. The hub attachment1620assembly 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 assembly1620can be applied to the portion of the filter that is external to the body for infusion.

The luer lock1644is generally known in the art and not describe in detail herein. As shown the luer lock1644has an internal passageway or lumen from the first end1648to a second end1652. In the second end1652is an opening1656configured in size and shape to accept a proximal end1660of the non-perforated section1644filter wire. The opening extends toward the proximal end of the luer lock1644to a establish fluid (or there material state) passageway with the fluid chamber1640. Through this fluid passageway medication or other material may be provided to the filter wire1600. The medication or other material may be pressurized in the fluid chamber1640to 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 chamber1640to the filter wire.

The luer lock1644also includes an outer ring1664with internal threaded which rotationally interact with an externally threaded inner frame1668of the luer lock. Through rotational movement of the outer ring1664relative to the inner frame1668the outer ring moves in the linear direction between the proximal end1648and the distal end1652.

The movement of the outer ring1664relative to the inner frame1668crushes an compression element1670that when crushed closes the passage between the chamber1640and the internal passageway in the filter1600. The compression element1670may comprise any material capable of performing as described herein. The compression element1670is a known structure in the luer lock1646and it may also be known to pinch or otherwise close the flow of medication or other material into the filter1600.

In one configuration the non-perforated section1634of the filter in contact with the compression element1670may comprise a different material or configuration than the portion of the filter not in contact with the compression element. For example, the non-perforated section1634of the filter in contact with the compression element1670may be flexible and resilient to return to shape after opening, while the perforated section1630may comprise a more stiff material capable of functioning as described above as a filter in a vascular environment.

FIG.21Billustrates the assembly ofFIG.21Awith the compression element compressed to close the inner lumen of the view of the filter. As shown the outer ring1664is twisted relative to the inner frame1668to compress (shown at element1671) the compression element1670, which in turn compresses the inner passageway or lumen to stop the flow of medication or other material.

Also shown inFIG.21Ais a close up view1631of the perforated section1630of the filter. Each of the dots in the coiled filter wire comprise opening or holes through which the medication or other material may pass into the blood steam

FIG.22illustrates a more detailed version of the filter. As shown the perforated section1630of the filter includes an outer wall1680which forms an inner passage1678or lumen through which medication or other material may flow or be placed. Perforating through the wall1680are openings1684which provide passages for the medication or other material to exit the inner passageway1678or lumen and enter the bloodstream. The openings1684, which may referred to herein as infusion pores or diffusion pores, may be of any various size and shape and such size and shape may depend on the medication or other material, dosing requirements, patient condition or numerous other factors.

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.

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.

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.

The above-described vascular filters may also be inserted and removed by other methods. InFIG.23, the needle400is inserted into a patient's vein, such as the common femoral vein. A guidewire2310is inserted through the needle400into the vein. The guidewire2310may have a curved tip2312, such as a u-shaped or a j-shaped tip to facilitate navigation of the guidewire2310through the vein and to prevent catching of the guidewire on the vein. The guidewire2310may be stored on a reel or other storage device, or inserted as a length of wire. When the guidewire2310is deployed in the vein, the needle400may be removed as shown inFIG.24.

In addition and in reference toFIG.25, the guidewire may also be used to establish a sheath or catheter2510in a patient. As shown, a sheath or catheter2510is utilized to deploy the vascular filter, as will be described in more detail below. The catheter2510has a proximal end2512and a distal end2514. A proximal end of the guidewire2310outside of the patient is inserted into the distal end2514of the catheter2510, and the catheter is guided over the guidewire2310to be inserted into the patient. In this manner, the catheter2510is inserted into the patient's vein at a predetermined location along the guidewire2310. The guidewire2310acts as a guide for the catheter. Once the catheter2510is properly placed within the vein, the guidewire2310is removed by pulling the guidewire2310out from the proximal end2512of the catheter2510as shown inFIG.26. It is also contemplated that the guidewire2510may be left in place to facilitate filter removal, or for other medical procedures.

With the catheter2510in place, the filter may be inserted in a manner similar as explained with reference toFIGS.7-11above. That is, as shown inFIG.27, a filter dispenser700may connect with and insert a distal end of the filter900into the proximal end2512of the catheter2510. When the filter900exits the distal end2514of the catheter2510, residual stresses in the filter900cause the filter wire to coil and form the filter within the patient's vein. In other embodiments deployment in a manner other than coiling may occur.

InFIG.28, the proximal end of the catheter2510(or sheath) is configured with a valve or seal on or in the exposed end that allows the filter wire (or guide wire) to be placed and advanced/withdrawn without allowing air into the catheter or blood from escaping from the catheter. In this configuration, a “plug” may be mainly used to prevent the wire from advancing further into thee vein. This plug may be referred to as a “wire fixation clamp or plug”. In another embodiment, the catheter2510is plugged by a fixation plug2810or any other device or element such as tape, adhesive, ring/loop or the like. The fixation plug2810holds the filter900in position with respect to the inserted catheter2510and may prevent infection while the filter900is in place. The catheter2510may be plugged with the fixation plug2810or other element to prevent blood flow from the catheter.

Removal of the filter is shown inFIGS.29and30. Here, the filter900is removed by pulling the filter900through the catheter2510and out of the proximal end2512of the catheter. Once the filter900is removed, the catheter2510is then removed. In this embodiment, the filter900may be safely and easily removed by way of the catheter2510inserted in the patient. This is due to the pulling force on the filter900to be substantially parallel to the vein with the filter is removed through the catheter2510. The catheter2510also protects the skin and vein by providing a protective wall between the filter900and the skin and vein. It is contemplated that this system may be used with any type filter such as a filter having an interior passage and outlets for medication disbursement. The filter900may also be of any shape and having one or more barbs or rough surfaces to catch the edge of the vein. The filter900material may also be smooth to prevent adhesion to the veins.

Further modifications may be made within the scope of the invention. For example, as shown inFIG.31, the filter may be configured to have an “umbrella” end3100. That is, the end of the filter may be split into several different threads. The filter may deploy from the needle or catheter. The residual stresses within the threads of the umbrella end expand the threads into the umbrella shape3100once deployed from the needle400(a catheter such as catheter2510may also be used). The threads of the umbrella filter3100are formed to be flexible such that when the filter is removed, as shown inFIG.32, the threads flex back and allow easy removal from the vein. It also contemplated that for removal, a flexible sheath may be inserted through a placement needle until the sheath contacts the umbrella portion of the filter causing the threads of the umbrella to collapse backwards and into the sheath for removal from the vessel. Although discussed for use in vein, it is contemplated that the filters may be used in any type or location of blood vessel.

FIG.34shows an infusion filter placed in the leg for treatment, according to one embodiment. InFIG.34, a leg3400of a patient is shown that has a clot3404within a vein3404. Such clots3404may extend a substantial length through the vein3402as shown. One method of treating clots3404is via thrombolysis, as previously explained. In this embodiment, a new infusion filter3410is provided to perform the thrombolysis to remove the clot, as will be explained in more detail below.

FIG.35shows an infusion filter design, according to one embodiment. It should be noted that the infusion filter design is not shown to scale, but rather the features are shown to aid in understanding. The relative lengths and sizes of the features in the filter design may vary. InFIG.35, an infusion filter3410comprises a wire with a first proximal length3512. The first proximal length3512is comprised of a hollow inner lumen for fluid transfer with solid circumferential outer wall which is non-permeable. Distally from the first proximal length3512is an infusion portion3514of the wire that is composed of a permeable outer wall. In one embodiment, the infusion portion3514may be formed to have a plurality of holes manufactured therein. Other methods to produce the infusion portion3514of the wire3410may also be used.

FIG.36Ashows an enlarged distal end of an infusion filter design, andFIG.36Bshows medicine infusion from the enlarged distal end shown inFIG.36A, according to one embodiment. As shown inFIG.36A, the infusion portion3514may comprise several manufactured holes3620. The holes3620may be manufactured via punching, penetrating, or molding the infusion portion3514, among other methods. Alternately, the infusion portion3514may be designed with as woven techniques or materials that are fabricated with micro pores, as well as other means. InFIG.36B, medication or other fluids3622is shown leaving the infusion portion3514via the holes3620. In this manner, medication or fluid may be transported to a specific location in a vein or other blood vessel.

Returning toFIG.35, the infusion filter3410further comprises a filter portion3516of the wire at a distal end of the infusion filter3410. The filter portion3410can be configured into a helix shape, a vortex shape, a nested shape, a tangled web shape, or any other suitable filter shape and can be either porous or non-porous depending on the materials used and their configuration. Similar to the filters described above, the filter portion3516is configured with residual stresses or surface tensions such that the filter3516takes shape once deployed from a sheath or catheter within a blood vessel.

On the proximal end of the filter3410, a luer lock type adaptor3518is 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.

As shown inFIG.34, the filter3410is inserted into the vein3402from an access point around the knee area3406of the leg3400. The filter3410is then inserted through the clot3404so that the filter portion3516can be deployed downstream in the vein3402from the clot3404.FIG.37shows a device for placing an infusion filter, according to one exemplary embodiment. An infusion device specific for wires such as a Tuohy-Borst Adapter may be used. InFIG.37, a configuration for deployment is illustrated where the filter portion3516of the infusion filter wire3410is loaded in a straight configuration within an outer cover3724. The filter portion3516is deployed when advanced through a catheter or sheath by inserting the outer cover3724into the opening of a catheter or sheath then advancing the filter wire3410through the vein until it is at the desired location. The filter portion3516is then advanced out of the outer cover3724until the filter portion3516assumes it neutral coiled or previously preconfigured design. The outer cover3724is then removed by way of a peel-away design commonly used in the field. In other embodiments, the filter wire3410can be configured with or without the luer lock3518and can be connected directly for infusion using a Tuohy Borst infusion connecter. In this configuration the deployment cover, catheter or sheath can be removed without need for peal-away design.

FIG.38Ashows a wire and filter for a system for performing thrombolysis,FIG.38Bshows a catheter for the system for performing thrombolysis, andFIG.38Cshows the combination of the wire and catheter ofFIGS.38A and38B, according to one embodiment. It should be noted that the wire and catheter described below are not shown to scale, but rather the features are shown to aid in understanding. InFIG.38A, a filter wire3810is provided with a filter portion3816at a distal end of a wire extension portion3812. The wire extension portion extends through the access point of the patient and into the blood vessel to deploy the filter portion3816at the desired location. The filter wire3810comprises a stopper3826proximal to the filter portion3816. The wire3810is configured to be deployed within the vein as described in other embodiments above.

As shown inFIG.38B, an infusion catheter3830is also provided. The catheter3830comprises a luer lock type device3836on a proximal end to which tubing or other equipment may be attached to dispense medicine or fluid into the catheter. The catheter3830further comprises a non-infusible length3832extending distally from the luer lock device3836. The non-infusible length3832is configured to extend through the incision in a patient and extend into the vein of the patient and includes an interior lumen to transport a fluid. An infusible length3834extends distally from the non-infusible length3832. The infusible length3834may comprise several holes or may be constructed to be otherwise permeable such that a fluid or medication flowing from the non-infusible length3832is conveyed from the interior lumen of the infusible length3835to the outside of the infusible length3835.

As shown inFIG.38C, when the catheter3830and the filter wire3810are deployed, the catheter3830extends over and covers the filter wire3810up to the stopper3826. The stopper3826is configured to block the flow of fluid from within the lumen of the catheter3830such that the fluid is forced to flow through the holes (or other permeable construction) of the infusion length3834of the catheter3830and into the blood vessel. The stopper3862may be omitted in some embodiments where the distal tip of the catheter3830is configured with a small valve (such as for example a distal end flow valve) which creates a seal around the wire3810. This allows infusion with a bare wire extending beyond the tip while still creating a seal in which pressure can develop in the catheter to infusion of medication or other substance into the bloodstream can occur.

FIG.39shows a method for performing venous thrombolysis, according to an exemplary embodiment. In step3902, a medical professional deploys a guide wire into and through a blood clot of a patient. For example, as shown inFIG.34, a patient may have a blood clot3404in an upper leg3400that extends through a vein3402in the upper leg3400. The guide wire is inserted into the vein upstream from the clot and is directed completely through the clot until a distal end of the guidewire reaches a downstream side of the clot. Once the guidewire is positioned, a catheter is inserted over the guidewire, as described in step3904. With catheter in position, the guide wire may then be removed.

In step3906, 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 step3908. 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 step3910.

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.

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 step3912, 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.

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.

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 toFIGS.38A-38C. The filter portion of the infusion filter might also be deployed via a sheath and a filter cover, as described with reference toFIG.37. Other modification or combinations with any other embodiments described herein may also be utilized.

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.