1. Field of the Invention
The present invention is generally related to a device for treating a lesion in a vessel, particularly a chronic lesion in a vessel located in a lower limb.
2. Background of the Invention
In a typical percutaneous transluminal coronary angioplasty (PTCA) procedure, a guiding catheter is percutaneously introduced into the cardiovascular system of a patient. The guide catheter is advanced through a vessel until the distal end thereof is at the desired location in the vasculature. A guidewire and a dilatation catheter having a balloon on the distal end thereof are introduced into the guiding catheter with the guidewire sliding through the dilatation catheter. The guidewire is first advanced out of the guiding catheter into the patient's coronary vasculature, and the dilatation catheter is advanced over the previously advanced guidewire until the dilatation balloon is properly positioned across the lesion.
Once in position, the flexible, expandable, preformed balloon is inflated to a predetermined size with a liquid or gas at relatively high pressures (e.g., about ten to twelve atmospheres) to radially compress the arthrosclerotic plaque in the lesion against the inside of the vessel wall and thereby dilate the lumen of the vessel. The balloon is then deflated to a small profile so that the dilatation catheter may be withdrawn from the patient's vasculature and blood flow resumed through the dilated vessel.
Vessels which have undergone angioplasty frequently suffer from restenosis, which is an abrupt closure of the vessel that may quickly block the flow of blood. Therefore, therapeutic substances, such as anti-coagulants, are typically applied to an area of the vessel which has recently undergone angioplasty, usually immediately following the procedure.
Different devices have been used to deliver the therapeutic substances to a vessel that has recently undergone angioplasty. For example, porous balloon catheters have been used to deliver therapeutic substances from within the lumen of the vessel. Generally, such catheters are configured similar to conventional dilatation balloon catheters with the modification of small holes formed into the balloon through which a therapeutic substance may flow under pressure. The substance is also used as the inflation medium for the balloon. Although the inflated balloon places the perfusion outlets in close proximity to the vessel wall to be treated, expulsion of the therapeutic substance may require full inflation of the balloon, which may temporarily block the vessel being treated. Interruption of blood flow through the vessel is undesirable because it can cause pain and discomfort to the patient.
Another example of a device that is configured to deliver a therapeutic substance (or substances) to the area of the vessel that has recently undergone angioplasty is a prosthetic device having a matrix material that is placed on the outside of the vessel. The prosthetic device incorporates the therapeutic substance and locally eludes the substance at a predefined rate. The matrix material is configured to permit the loading of an adequate quantity of the therapeutic substance, and elude the therapeutic substance at an appropriate well-defined rate over time.
It is desirable to treat the area of the vessel that has recently undergone angioplasty with greater control in terms of the amount and timing of the therapeutic substance being provided to the area, while minimizing discomfort to the patient. In addition, it is desirable to be able to more directly treat the site of the lesion.
Embodiments of the present invention describe an apparatus and method to treat a site of a lesion in a vessel. Embodiments described herein may be particularly suited for treating chronic lesions located in the lower limbs, such as the femoral artery, the peroneal artery, or the posterior artery.
According to an aspect of the present invention, there is provided a cuff device configured to treat a site of a lesion in a vessel. The cuff device includes a flexible material having a first surface and a second surface. The flexible material is configured to be wrapped around an exterior surface of the vessel so that the first surface of the flexible material is in contact with an exterior surface of the vessel. The cuff device also includes an opening that extends from the first surface to the second surface. The opening is constructed and arranged to allow a needle of a syringe to pass therethrough.
According to an aspect of the invention, there is provided a method for treating a site of a lesion in a vessel. The method also includes placing a flexible material around an exterior surface of the vessel, and locating an opening in the flexible material. The method includes passing a needle of a syringe through the opening and into the vessel, and injecting the vessel with a therapeutic substance with the syringe.
According to an aspect of the invention, there is provided a method for treating a site of a lesion in a vessel. The method includes placing a flexible material of a cuff device around an exterior surface of the vessel, and passing a tube of the cuff device that extends from the flexible material through skin. The method also includes passing a needle of a syringe through the tube and through an opening in the flexible material, and injecting the vessel with a therapeutic substance with the syringe.
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:
The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and use of the invention. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.
The vessel 10 may be initially treated to open up the lumen 16 at the site of the lesion 18 using known methods. For example, as illustrated in
After the lumen 16 has been opened at the site of the lesion 18, there may be a risk of restenosis, as discussed above. To reduce the risk, a cuff device 30 according to embodiments of the invention may be used to treat the site of the lesion 18 with a therapeutic substance or agent. The cuff device 30 is configured to allow clinician to locate the site of the lesion 18 and apply the therapeutic substance to the site of the lesion 18, as discussed in further detail below. Depending on the location of the vessel 10, key-hole surgery or a direct cut down may be used to access the vessel 10, as known in the art, so that the cuff device 30 may be attached to the outer surface 12 of the vessel 10 at the site of the lesion 18.
As shown in
The flexible material 32 may include a flexible mesh of fibers that may be woven together. In an embodiment, the fibers may comprise polyethylene terephthatlate (“PET”), such as PET fibers sold under the trademark DACRON. Once the cuff device 30 is wrapped around the vessel 10, it desirably flexes in the radial direction, as the vessel 10 moves, yet not move relative to the vessel 10, such as in a longitudinal direction along the vessel 10.
The flexible material 32 may be secured around the vessel 10 by use of an attachment structure 38 that is configured to allow the flexible material 32 to wrap around the vessel 10 and onto itself, similar to a self-adhering bandage that is wrapped around a finger. The attachment structure 38 may include an adhesive, a hook and loop structure, or any other suitable material or configuration that allows the cuff device 30 to be secured in place. In an embodiment, an adhesive in between the first surface 34 of the flexible material 32 and the outer surface 12 of the vessel 10 may be used in addition to the attachment structure 38 for securement of the cuff device 30 directly to the vessel 10.
As illustrated in
As illustrated, the openings 40 are located longitudinally along the cuff device 30. When the cuff device 30 is secured to the vessel 10, the openings 40 are desirably positioned to allow easy access to the openings 40 by the needle 42. For example, when the cuff device 30 is attached to the vessel 10, the openings 40 should face outwardly and towards the skin of the patient so that the distance between the skin and the openings 40 is as short as possible. Such positioning of the openings 40 may allow for easy access by the syringe 44 and minimize any discomfort to the patient.
The use of the openings 40 in the cuff device 30 may eliminate the need to preload the above-described prosthetic device with the therapeutic substance. The use of the openings 40 may also eliminate the need to configure the prosthetic device to elute the substance at a well-defined predetermined rate. The openings 40 of the cuff device 30 may offer direct control over the type and amount of therapeutic substance that is injected, as well as the timing of the injections. Also, the openings 40 incorporate the option of providing a very specific injection location within the lesion site itself.
As illustrated in
Although the self-sealing membrane 48 is illustrated as being a single membrane that covers all of the openings 40 on the second surface 36 of the flexible material 32, the illustrated embodiment should not be considered to be limiting in any way. For example, in an embodiment, individual self-sealing membranes may be provided to each opening at either end of the opening 40, i.e., at the first surface 34 or at the second surface 36 of the flexible material 32, or even within each opening 40.
The cuff device 30 may also include a radiopaque material in the form of a radiopaque marker 50 that may be positioned beside each opening 40, or even line each opening 40. The radiopaque markers 50 may assist the clinician with locating the openings 40 in the cuff device 30 so that the needle 42 of the syringe 44 may be properly aligned during treatment. Also, the radiopaque markers 50 may assist the clinician with the initial placement of the cuff device 30 on the vessel 10 so that the openings 40 are properly oriented, as discussed above.
The radiopaque marker 50 may be any suitable marker that is configured to be visible in a radiographic image, such as an x-ray or fluoroscopic image. Radiopaque materials do not allow certain wavelengths of radiation, such as x-rays, to pass through, which allows the clinician to see the radiopaque material in a human body when using suitable visualization equipment, such as a fluoroscope. Any suitable radiopaque material that allows the radiopaque marker 50 to be imaged with imaging equipment, while allowing the cuff device 30 to maintain flexibility, may be used. Examples of such radiopaque materials include, but are not limited to metals such as gold, platinum, and alloys thereof, and filled polymeric materials, such as barium sulfate loaded silicone, polyimide, and polycarbonate.
As shown in
The flexible material 62 may be secured around the vessel 10 with an attachment structure 68, such as an adhesive or a hook and loop structure, which is configured to allow the flexible material 62 wrap around the vessel 10 and onto itself. Similar to the flexible material 32 described above, the flexible material 62 may include a mesh of woven fibers, such as PET fibers sold under the trademark DACRON, or any other suitable material. In an embodiment, an adhesive may be used in between the first surface 64 of the flexible material 62 and the outer surface 12 of the vessel 10 for additional securement to the vessel 10. The cuff device 60 is configured to be able to flex in the radial direction with movement of the vessel 10, yet not move longitudinally along the vessel 10, once the cuff device 60 is wrapped around the vessel 10.
The cuff device 60 also includes a plurality of openings 70, or so-called ports. Similar to the openings 40 described above, each opening 70 extends through the flexible member 62 from the first surface 64 to the second surface 66. Each opening 70 may be defined by a tube 72 that extends from the first surface 64 of the flexible material 62, through the flexible material 62, and outward from the second surface 66 of the flexible material 62.
In an embodiment, the tube 72 may not pass through the flexible material 62 but may instead be attached to the second surface 66 of the flexible material 62 so that it is aligned with the opening 70. In such an embodiment, the opening 70 is not defined by the tube 72, but may have a diameter that is substantially the same as the inner diameter of the tube 72 and be aligned with the tube 72 so that the needle 42 described above may be inserted smoothly through the tube 72 and the opening 70.
Each tube 72 is configured to receive the needle 42 of the syringe 44 so that the needle 42 may be inserted into the wall 14 of the vessel 10 and even into the lesion 18, as described above. Once the needle 42 has been inserted into the desired location of the wall 14 or lesion 18, the therapeutic substance or agent 46, such as any of the substances or agents listed above, may be injected to the site of the lesion 18. Similar to the embodiment of the cuff device 30 described above, the tubes 72 and openings 70 are located longitudinally along the cuff device 60 so that the therapeutic substance 46 may be injected to the desired location along the site of the lesion 18.
The tubes 72 may be constructed and arranged to be visible in a radiographic image, such as an x-ray or fluoroscopic image, during placement of the cuff device 60 on the vessel 10. In an embodiment, each tube 72 is made from a radiopaque material, such as gold, platinum, or an alloy thereof, or a filled polymeric material, such as barium sulfate loaded silicone, polyimide, or polycarbonate, or any other suitable radiopaque material.
As illustrated in
As shown in
Although not depicted in
Embodiments of the cuff device 30, 60 described herein may be particularly suitable to treat chronic lesions, especially lesions located in vessels in the lower limbs, such as the femoral artery, the peroneal artery, and posterior tibial artery. The cuff device 30, 60 may be surgically attached to the vessel 10 and configured to be in place for an extended period of time. Continuous treatment of the affected site with suitable therapeutic substances may be provided by using the plurality of openings 40, 70 in the flexible member 32, 62. Such continuous treatment may assist in the prevention of restenosis, especially for high risk patients, including but not limited to diabetics.
If desired, the cuff device 30, 60 may be removed by surgically accessing the vessel 10 when treatment has concluded, or if it is desirable to replace the cuff device 30, 60. A new cuff device 30, 60 having the same or a different configuration may be wrapped around the vessel 10 so that treatment may continue, if desired.
While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient roadmap for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.