Patent Application
20110301502
This disclosure relates generally to devices, systems and methods for positioning an apparatus in a vessel.
Coronary artery disease is the most common cause of death in the adult population in both sexes in the United States of America. Chronic total occlusion (CTO) is the complete blockage of a blood vessel and usually has serious consequences, such as a heart attack, if not treated in a proper, safe and timely fashion. The cause of blockage could be the deposition of atheromatous plaque, old thrombus or similar other deposits in the body vessel. When these coronary lesions (CTOs) become very severe, they can either be treated by coronary intervention using catheters or coronary bypass surgery. A popular method of removal of such occlusions is by coronary intervention as it is less invasive than surgery.
Coronary intervention may include the following steps: A) coronary cannulation: A long catheter is advanced through the femoral artery near the groin area to the ostium of the coronary arteries carrying the lesions. Radiopaque contrast may be injected to identify the site of blockage in the lumens of the vasculature. B) Guidewire placement: A soft non-traumatic guidewire is advanced through the coronary catheter. This guidewire crosses the obstructive lesion and is advanced through the entire length of the vessel. This guidewire acts as a track over which further instrumentation is advanced. This step is often the pivotal point in determining the success of the intervention. The placement of the guidewire is the most challenging aspect in complicated cases for the physician. C) Stent deployment: After the wire is properly positioned, a catheter that carries a stent at its distal end over an inflatable part of this catheter is advanced over the guidewire. The stent is positioned accurately at the site of the blockage. After the stent has been properly positioned the balloon is inflated thus releasing the stent and at the same time flattening the plaque. D) Post procedure confirmation: The guidewire and catheter, which was carrying the stent, are removed and a post-procedure angiogram is done to demonstrate the success of the intervention.
Safe and successful recanalization of an occluded body vessel depends on precise positioning and insertion of the guidewire into the occluded body vessel. This involves steering the guidewire to negotiate curves and bifurcations of vessels. Some lesions are present in branches that diverge from the parent vessel at varying angles, as much as 90 degrees or more. In general, the guidewire must often pass through several bends and curves before reaching the target lesion and these obstacles need different angulation and curvature of the guidewire for successful passage. The situation becomes more challenging when occlusions are present in narrow branch body vessels that are to be accessed by advancing a soft, non-traumatic tip guidewire through a main body vessel leading to the branch vessel. In such cases, the chances of erroneous diversion of such a guidewire into an unintended location such as the subintimal space or puncturing the vessel wall are very high.
Known methods to access a targeted branch body vessel either use catheter devices that have deflectable tips or employ deflectable tip guidewires. These devices have a distal tip which is capable of being deflected by the operator to a desired angle for successful penetration into a targeted branch body vessel. Devices and methods for placing bifurcated stents at branch locations in a main body vessel also use mechanisms to deflect guidewires into side branches.
While using the deflectable tip catheters and guidewire devices to access a targeted branch body vessel, the device is inserted into a main body vessel to a suitable location near the bifurcation point and thereafter the deflectable tip of the device is used to steer a guidewire into the targeted branch body vessel.
U.S. Patent Publication No. 2009/0264980 to Mackay and U.S. Pat. No. 7,089,063 to Lesh et al. and U.S. Patent Publication No. 2009/0005755 to Keith et al. disclose catheters which employ deflectable tips for placing a guidewire into a targeted branched body vessel. As a variation, some catheters may have a flexible tip at the distal end which can be curved in any direction by the operator. For guiding a guidewire into a branched body vessel, these catheters are inserted in the main body vessel and the curved tip of the catheter is placed pointing towards target branch body vessel. Thereafter, a guidewire is advanced through the catheter and into target branch of the body vessel.
U.S. Pat. No. 5,916,194 to Jacobsen et al. discloses an apparatus for directing a guidewire from a catheter to a target branch vessel. This apparatus comprises a catheter with a guidewire lumen, a shapeable distal end of the catheter, an opening in the catheter's distal sidewalls and an expandable balloon at the distal end. The distal end of the catheter is deflectable by expanding the balloon to deflect and guide a guidewire into a target body vessel.
U.S. Patent Publication No. 2004/0116832 to Friedrich et al. describes a catheter arrangement for guiding a guidewire into a branch body vessel. The device comprises two catheters which are arranged coaxially and are movable with respect to each other. The inner catheter has a pre-bent distal tip for guiding a guidewire into a target body vessel. The tilt of the pre-bent distal tip of the inner catheter can be controlled by the axial movement of the inner catheter in the outer catheter.
U.S. Pat. No. 7,371,248 to Dapolito et al. discloses a guidewire and method for steering it through tortuous vessels. This type of guidewire comprises a hollow shaft and a core wire therein and a tubular protection element at its distal end. The shaft and the core wire control deployed and collapsed configurations of the tubular protection element. Further, the application of axial tension on the protection element creates a curvature at the distal end of the guidewire which is used for steering the guidewire through tortuous vessels.
U.S. Patent Publication No. 2006/0259009 to Murray, published PCT application WO/2006/046244A2 to Turgeman et al. and U.S. Patent Publication No. 2009/0306757 to Meyer et al. disclose apparatus for diverting a guidewire through a bifurcated passageway. The device of the Turgeman publication features an elongated hollow shaft bifurcated by a partitioning element at the distal section into separate first and second lumens, with suitable feature for deflecting a guidewire. U.S. Patent Publication No. 2009/0306757 to Meyer et al. disclosing a wiring assist device includes guidewire housing members and multiple lumen arrangement for parallel and angled orientation of the guidewires. U.S. Patent Publication No. 2006/0259009 to Murray discloses a guidewire loader catheter having two lumens attached tangentially to each other with one lumen extending beyond the other at the distal end.
The guidewire positioning devices described above may suffer from various complexities and/or constraints of operation, structure and size. Even when the operator succeeds in positioning the distal end of the guidewire into a targeted branched body vessel by any of the above stated methods, the operator may not be able to successfully and safely advance the guidewire further into the branched vessel due to problems of guidewire coiling up or slipping back of the guidewire into the main body vessel on repeated pushing. Additionally, due to the anatomy or composition of the vessel and/or an occlusion within the vessel, it may be difficult to position an apparatus at a desired location within the vessel. For example, it may be difficult to position a stent within an occluded vessel due to the torturous vasculature, anatomy of the occlusion cap, the hardness of the occlusion, or the like. The difficulty in positioning the apparatus may lead to repeated attempts and the application of additional force by the operator, which may cause complications such as damage to the vascular wall. Therefore, there exists the need for devices, methods, and systems where a positioning device is configured to position or facilitating the positioning of an apparatus in the vessel.
Described herein are devices, methods, and systems for positioning an apparatus in a vessel.
In one aspect, a device for positioning an apparatus in a vessel comprises a distal end, a proximal end, and an elongated body disposed in-between. The elongated body of the positioning device is configured to accommodate at least a portion of the apparatus. A cross-sectional area of a portion of the positioning device is configured to be smaller than a cross-sectional area of the apparatus and wherein at least portion of the cross-sectional area of the positioning device is configured to be expandable or to increase.
In another aspect, at least a portion of the elongated body of the positioning device is configured to decrease in cross-sectional area from the proximal to the distal end. In another aspect, the positioning device comprises a longitudinal opening disposed along a side of the elongated body. The longitudinal opening may be configured to allow the cross-sectional area of at least a portion of the elongated body to expand or to increase. In one aspect, the longitudinal opening may be defined by a first and second portion of the elongated body. In one aspect, the two portions are configured to overlap. In another aspect, the two portions are elastically separable. In one aspect, the two portions are configured to move away from each other when force is applied to expand the cross-sectional area of at least a portion of the elongated body.
In yet another aspect, the positioning device comprises a wire configured to support the elongated body. In one aspect, the wire may extend through at least a portion of a length of the elongated body. In another aspect, the positioning device further comprises a torquing means to transfer torque to the wire.
Also disclosed herein are methods of positioning an apparatus in a vessel. In one aspect, a method of positioning an apparatus in a vessel comprises inserting a positioning device comprising a distal end, a proximal end and an elongated body disposed in between into the vessel, inserting at least a portion of the apparatus into the elongated body of the positioning device, wherein a cross-sectional area of the positioning device is smaller than cross-sectional area of the apparatus, separating the apparatus and the positioning device by expanding or increasing the cross-sectional area of the distal end and advancing the apparatus through the positioning device, and positioning the apparatus in the vessel.
In one aspect, the positioning device comprises a longitudinal opening defined by a first portion and a second portion, wherein the separating is achieved by moving the first and second portion away from each other.
In another aspect, a portion of an occlusion in the vessel may be penetrated using the distal end of the positioning device and positioning the apparatus at the occlusion in the vessel.
In yet another aspect, the apparatus configured to be positioned by the positioning device is a stent and the stent is inserted into the positioning device in a collapsed configuration. The stent may be expanded once the stent has been positioned in the vessel.
This, and further aspects of the present embodiments are set forth herein.
Although the detailed description contains many specifics, these should not be construed as limiting the scope of the disclosure but merely as illustrating different examples and aspects of the disclosure. It should be appreciated that the scope of the disclosure includes other embodiments not discussed in herein. Various other modifications, changes and variations which will be apparent to those skilled in the art may be made in the arrangement, operation and details of the method and apparatus disclosed herein without departing from the spirit and scope of the disclosure as described here.
The present devices, methods, and systems contemplate embodiments where a positioning device is configured to position or to facilitate the positioning of an apparatus in the vessel. Due to the anatomy or composition of the vessel and/or an occlusion within the vessel, it may be difficult to position an apparatus at a desired location within the vessel. For example, it may be difficult to position a stent within an occluded vessel due to the torturous vasculature, anatomy of the occlusion cap, the hardness of the occlusion, or the like. The difficulty in positioning the apparatus may lead to repeated attempts and the application of additional force by the operator, which may cause complications such as damage to the vascular wall.
Briefly stated, the devices, methods, and systems disclosed herein contemplate embodiments where a positioning device is configured to position an apparatus, such as a stent, in the vessel by housing the apparatus within an elongated body of the positioning device. Once the apparatus is positioned at or near a desired location, the positioning device is configured to separate from the apparatus such that the apparatus is positioned in the vessel. The disclosed embodiments may minimize repeated attempts of positioning an apparatus into a vessel and enable rapid and safe apparatus positioning procedures to be carried out, while increasing patient comfort and safety as well as reducing fatigue to the operator.
As referred to herein, a vessel could be any vessel or artery in which blood flows through the hollow tubular cavity as well as any duct within the body. Also, referred to herein, an apparatus may be any device used to treat an indication in the vessel, such as weakened vessel, occlusion in the vessel, or the like. In one embodiment, the apparatus may be a device configured to penetrate, weaken, and/or recanalize an occlusion such as an atheromatous plaque, an old thrombus, or other similar deposit. In another embodiment, the apparatus may be a stent, such as a drug eluting stent, a covered stent, balloon expandable stent, bare-metal stent, self-expanding stent, or the like that may be inserted into the vessel to support the vessel wall and/or to prevent restenosis. Additionally and optionally, the apparatus may be a visualization element, therapeutic agent delivery element, or the like.
As shown in
Alternatively, in another embodiment the elongated body disposed in-between the proximal end and the distal end may be substantially continuous without any longitudinal openings. In yet another embodiment, the elongated body may comprise one or more openings that extend along a partial length of the elongated body. For example, the elongated body may comprise one or more slit openings disposed longitudinally on the elongated body, wherein the slit openings extend along a portion of the elongated body instead of the entire length of the elongated body as shown in
The cross-sectional area or the diameter of positioning device 100 may be configured to decrease from a proximal end 130 towards the distal end 120, whereby the positioning device 100 assumes a substantially tapered or conical configuration. The tapered configuration improves maneuverability and navigation of the positioning device 100, particularly in narrow or tortuous vasculature. Furthermore, the tapered configuration where the distal end 120 is substantially narrow may create a sharp tip that facilitates occlusion penetration. Alternatively, the guidewire positioning device may comprise a substantially cylindrical or blunt distal end.
In one embodiment, the positioning device 100 may comprise a substantially flat opening at its proximal end 130 as shown in
Two cross-sectional views of the positioning device are shown in
Additionally and optionally, the positioning device may be constructed of a flexible, elastic and/or shape-memory material. For example, the positioning device may be constructed of various materials that exhibit sufficient strength, elasticity, and/or flexibility such as polyvinyl chloride, cross-linked polyethylene, polyethylene terephthalate (Dacron), PET, nylon, latex, silicone, or the like. Additionally, the positioning device may be coated for lubrication, for abrasion resistance, or to deliver an anti-coagulatory drug or other therapeutic agents.
In one embodiment, the first and/or the second portions of the elongated body may be configured to alter the size and/or shape of the longitudinal opening and thereby altering the size, area, volume, and/or shape of the elongated body when a force is applied to the elongated body. In another embodiment, where the elongated body comprises one or more slit openings, the size and/or shape of the slit openings may be altered and thereby altering the size, area, volume, and/or shape of the elongated body. In yet another embodiment, where the elongated body is substantially continuous without any longitudinal openings, the size, area, volume and/or shape of the elongated body may be altered due to the elastic nature of the elongated body.
Referring now to
Additionally and optionally, the positioning device 500 may further comprise a support wire 550 configured to provide support for the positioning device 500 and to allow an operator to maneuver the positioning device 500. In one embodiment, the support wire 550 extends through substantially an entire length of the positioning device 500, thereby directly supporting substantially the entire length of the positioning device 500; in another embodiment, the support wire 550 extends through a portion of the positioning device 500.
The support wire 550 may comprise a single wire or multiple wires each having a solid cross-section. The support wire 550 may be constructed of helically wound wire or wires. Additionally, the support wire 550 may be either hollow or solid in one or more portions to maintain optimum flexibility during operation. In one embodiment, a portion of the support wire 550 may be configured with a decreasing diameter from the proximal end to the distal end. In another embodiment the stiffness of a portion of the wire shaft may be configured to decrease from the proximal end to the distal end. The support wire 550 may be constructed of any material with suitable properties that are well known in the art for surgical applications such as stainless steel, cobalt alloy, nickel-titanium, and the like.
The support wire 550 may be configured to be torquable by a torquing means (not shown) disposed on or near the proximal end of the support wire 550 for providing rotational torque to the support wire 550. Rotational torquing may help to position the positioning device 500 at a desired orientation or location in the vessel. The torquing means may be in the form of a spindle, a steering disk, a wheel, or the like that are known in the art. Furthermore, the torquing means may be configured to distinguish between a support wire 550, a guidewire, stent catheter 650, or the like by tactile feedback to facilitate the operation under decreased or minimal illumination.
The elongated body 510 of the positioning device 500 is configured to accommodate at least a portion of the stent 600. As seen in
The cross-sectional area of at least a portion of the positioning device 500 is configured to be expandable. In one embodiment, the first and/or second portion of the elongated body is configured to be moveable such that when the first portion and the second portion are moved away from each other, the cross-sectional area of a portion of the positioning device 500 is increased. The movement of the first and/or second portion of the positioning device 500 may be caused by a force applied to the elongated body 510. In one embodiment, a force is applied to an internal surface of the elongated body 510 thereby forcing the first and/or the second portion to move away from each other.
Specifically, in one embodiment, a force may be applied to the first and/or second portion by means of the apparatus such as the stent 600. In such embodiment, the force may be applied in the distal direction towards the distal end 520 of the positioning device 500 by the operator, wherein the force is transmitted to the stent 600 through the stent catheter 610. The distal directional force causes a portion of the stent 600 with a larger cross-sectional area than a portion of the positioning device 500 to transmit the force to a portion of the elongated body 510, such as the first and/or second portion. The force transmitted to the elongated body 510 thereby moves or pulls the first and/or second portion away from each other, which results in an increase to the cross-sectional area of a portion of the positioning device 500. In one embodiment, the cross-sectional area of the distal end 520 of the positioning device 500 is configured to increase upon receiving the distal directional force such that the cross-sectional area of the distal end 520 is increased by a degree where that the stent 600 may exit through the distal end 520 of the positioning device 500. Alternatively, in one embodiment where the elongated body of the positioning device is substantially continuous such that elongated body 510 is devoid of the longitudinal opening, the cross-sectional area of the elongated body may be increased as a result of the distal directional force as a result of the elastic and/or expandable property of the elongated body.
Additionally and optionally, the longitudinal opening 540 may be configured to accommodate at least a portion of the apparatus and/or a device associated with the apparatus such that a portion of the apparatus and/or the associated device may separate from the positioning device by passing through the longitudinal opening 540. In one embodiment, the longitudinal opening 540 may be configured to accommodate the stent catheter 610. In such embodiment, the stent catheter 540 may be inserted or removed from the positioning device 500 through the longitudinal opening 540.
Referring now to
At step 720 and as shown in
Alternatively, in another embodiment the positioning device 500 and the stent 600 may be coupled prior to the insertion of the positioning device 500 and the coupled positioning device 500 and the stent 600 may be inserted in tandem along the guidewire GW into the vessel and a portion of the occlusion OCL.
At step 730 and as shown in
Thereafter, the stent 600 is pushed distally through the distal end 520 of the positioning device 500 such that the stent 600 traverses the positioning device 500. Additionally and optionally, In an embodiment where the positioning device 500 comprises a longitudinal opening as seen in
At step 740, the stent 600 is transformed from the collapsed configuration into an expanded configuration whereby the expanded stent 600 occupies a greater volume within the vessel. The transformation of the stent 600 may be accomplished through various means depending on the nature of the stent 600. In one embodiment, where the stent 600 is a balloon expandable stent, a balloon (not shown) underneath the stent 600 is inflated, thereby expanding the stent 600.
It is contemplated that the various embodiments of the positioning device as described above may be constructed partially or completely of elastic material. Furthermore, the longitudinal or the slit openings may be configured to return to its original size or shape when the applied force is released. Furthermore, it is contemplated that the elongated body including the first and/or the second portions of the various embodiments may be configured to alter and to retain the altered size and/or shape for a period of time.
It is also contemplated that the various embodiments of the elongated body of the positioning device may be substantially cylindrical, or may assume various curvatures to facilitate insertion into the vessel. The curvature or tilt angle of the elongated body of the positioning device may be adjustable. In one embodiment, the curvatures of the elongated body may assume a substantially flat configuration to allow advancement through a vessel. Thereafter, the curvature of the elongated body may be adjusted such that the distal end of the positioning device may assume a curved configuration wherein the distal end may be placed at or near the branch vessel. It is further contemplated that the curvature may be adjusted throughout the operation to facilitate access and/or navigation within the body region.
The curvature or tilt angle of the elongated body may be pre-configured by using a shape memory material or other means known in the art during manufacture, or it may be configured by the operator prior to, or during the operation. It is further contemplated that the curvature may be variable and/or adjusted by the operator. In one embodiment, the angular orientation or curvature of the elongated body may be flattened by inserting a relatively stiffer portion of a support wire into the elongated body of the positioning device. The angular orientation may be varied as desired by withdrawing or advancing the softer portion of the support wire through the elongated body. Additionally and optionally, the elongated body may be embedded with a deformable wire, such as a plastically deformable wire, to configure the desired curvature or tilt angle.
It is further contemplated that the various embodiments of the positioning device may comprise radiopaque markers disposed on or near the proximal end and/or the distal end of the positioning device. The radiopaque markers may facilitate tracking the location of the positioning device, particularly, while the positioning device navigates through narrow and/or tortuous vasculature during the operation.
While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims.
This application is a continuation-in-part of U.S. patent application Ser. No. 13/027,102, filed on Feb. 14, 2011, which claims the benefit and priority of U.S. Provisional Application No. 61/304,265, filed on Feb. 12, 2010, the full disclosure of the above referenced applications are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61304265 | Feb 2010 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13027102 | Feb 2011 | US |
| Child | 13215076 | US |
