Delivery system and method for bifurcated graft
A flexible low profile delivery system for delivery of an expandable intracorporeal device, specifically, an endovascular graft, which has at least one belt circumferentially disposed about the device in a constraining configuration. The belt is released by a release member, such as a release wire, by retracting the wire from looped ends of the belt. Multiple belts can be used and can be released sequentially so as to control the order of release and placement of the endovascular graft. An outer protective sheath may be disposed about the endovascular graft while in a constrained state which must first be retracted or otherwise removed prior to release of the graft from a constrained state. The delivery system can be configured for delivery over a guiding device such as a guidewire. The delivery system can also be configured for delivery of bifurcated intracorporeal devices.
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This application is a continuation-in-part of U.S. patent application Ser. No. 09/917,371, filed Jul. 27, 2001, by Michael V. Chobotov et al., entitled “Delivery System and Method for Bifurcated Endovascular Graft”, which is a continuation-in-part of U.S. patent application Ser. No. 09/834,278, filed Apr. 11, 2001, by Michael V. Chobotov et al., entitled “Delivery System and Method for Endovascular Graft,” Each application is hereby incorporated by reference herein in its entirety.
BACKGROUNDThe present invention relates generally to a system and method for the treatment of disorders of the vasculature. More specifically, a system and method for treatment of thoracic or abdominal aortic aneurysm and the like, which is a condition manifested by expansion and weakening of the aorta. Prior methods of treating aneurysms have consisted of invasive surgical methods with graft placement within the affected vessel as a reinforcing member of the artery. However, such a procedure requires a surgical cut down to access the vessel, which in turn can result in a catastrophic rupture of the aneurysm due to the decreased external pressure from the surrounding organs and tissues, which are moved during the procedure to gain access to the vessel. Accordingly, surgical procedures can have a high mortality rate due to the possibility of the rupture discussed above in addition to other factors. Other risk factors for surgical treatment of aortic aneurysms can include poor physical condition of the patient due to blood loss, anuria, and low blood pressure associated with the aortic abdominal aneurysm. An example of a surgical procedure is described in a book entitled Surgical Treatment of Aortic Aneurysms by Cooley published in 1986 by W.B. Saunders Company.
Due to the inherent risks and complexities of surgical intervention, various attempts have been made to develop alternative methods for deployment of grafts within aortic aneurysms. One such method is the non-invasive technique of percutaneous delivery by a catheter-based system. Such a method is described in Lawrence, Jr. et al. in “Percutaneous endovascular graft: experimental evaluation”, Radiology (May 1987). Lawrence described therein the use of a Gianturco stent as disclosed in U.S. Pat. No. 4,580,568. The stent is used to position a Dacron fabric graft within the vessel. The Dacron graft is compressed within the catheter and then deployed within the vessel to be treated. A similar procedure has also been described by Mirich et al. in “Percutaneously placed endovascular grafts for aortic aneurysms: feasibility study,” Radiology (March 1989). Mirich describes therein a self-expanding metallic structure covered by a nylon fabric, with said structure being anchored by barbs at the proximal and distal ends.
One of the primary deficiencies of the existing percutaneous devices and methods has been that the grafts and the delivery systems used to deliver the grafts are relatively large in profile, often up to 24 French, and stiff in longitudinal bending. The large profile and relatively high bending stiffness of existing delivery systems makes delivery through the vessels of a patient difficult and can pose the risk of dissection or other trauma to the patient's vessels. In particular, the iliac arteries of a patient are often too narrow or irregular for the passage of existing percutaneous devices. Because of this, non-invasive percutaneous graft delivery for treatment of aortic aneurysm is contraindicated for many patients who would otherwise benefit from it.
What is needed is an endovascular graft and delivery system having a small outer diameter relative to existing systems and high flexibility to facilitate percutaneous delivery in patients who require such treatment. What is also needed is a delivery system for an endovascular graft that is simple, reliable and that can accurately and safely deploy an endovascular graft within a patient's body, lumen or vessel.
SUMMARYThe invention is directed generally to a delivery system for delivery of an expandable intracorporeal device, specifically, an endovascular graft. Embodiments of the invention are directed to percutaneous non-invasive delivery of endovascular grafts which eliminate the need for a surgical cut-down in order to access the afflicted artery or other intracorporeal conduit of the patient being treated. Such a non-invasive delivery system and method result in shorter procedure duration, expedited recovery times and lower risk of complication. The flexible low profile properties of some embodiments of the invention also make percutaneous non-invasive procedures for delivery of endovascular grafts available to patient populations that may not otherwise have such treatment available. For example, patients with small anatomies or particularly tortuous vasculature may be contraindicated for procedures that involve the use of delivery systems that do not have the flexible or low profile characteristics of embodiments of the present invention.
In one embodiment, the delivery system has an elongate shaft with a proximal section and a distal section. The distal section of the elongate shaft includes a portion having an expandable intracorporeal device. An elongate belt support member is disposed adjacent a portion of the expandable intracorporeal device and a belt is secured to the belt support member and circumferentially disposed about the expandable intracorporeal device. The belt member constrains at least a portion of the expandable intracorporeal device. A release member releasably secures the belt in the constraining configuration.
Another embodiment of the invention is directed to a delivery system that has an elongate shaft with a proximal section and a distal section. The distal section of the elongate shaft has an elongate belt support member disposed adjacent a portion of the expandable intracorporeal device. A belt is secured to the belt support member and is circumferentially disposed about the expandable intracorporeal device. The belt has a configuration which constrains the expandable intracorporeal device and a release member releasably secures the belt in the constraining configuration. The belt may constrain any portion of the expandable intracorporeal device, such as a self-expanding portion of the expandable intracorporeal device. A self-expanding portion of the device may include a self-expanding member such as a tubular stent.
In a particular embodiment of the invention, a plurality of belts are secured to various axial positions on the belt support member, are circumferentially disposed about the expandable intracorporeal device and have a configuration which constrains the expandable intracorporeal device. At least one release member releasably secures the belts in the constraining configuration. Each belt can be released by a single separate release member which engages each belt separately, or multiple belts can be released by a single release member. The order in which the belts are released can be determined by the axial position of the belts and the direction of movement of the release member.
Another embodiment of the invention is directed to a delivery system for delivery of a self-expanding endovascular graft with a flexible tubular body portion and at least one self-expanding member secured to an end of the endovascular graft. The delivery system has an elongate shaft having a proximal section and a distal section. The distal section of the elongate shaft has an elongate belt support member disposed within the self-expanding member of the endovascular graft and a belt that is secured to the belt support member adjacent the self-expanding member. The belt is also circumferentially disposed about the self-expanding member and has a configuration that constrains the self-expanding member. A release wire releasably secures ends of the belt in the constraining configuration.
A further embodiment of the invention includes a delivery system for delivery of an endovascular graft with a flexible tubular body portion and a plurality of self-expanding members secured to ends of the endovascular graft. The delivery system has an elongate shaft with a proximal section and a distal section. The distal section of the elongate shaft has an elongate guidewire tube disposed within the endovascular graft in a constrained state. A plurality of shape memory thin wire belts are secured to the guidewire tube respectively adjacent the self-expanding members. The belts are circumferentially disposed about the respective self-expanding members and have a configuration that constrains the respective self-expanding members. A first release wire releasably secures ends of the belts disposed about the self-expanding members at the proximal end of the endovascular graft in a constraining configuration. A second release wire releasably secures ends of the belts disposed about the self-expanding members at a distal end of the endovascular graft in the constraining configuration.
The invention also is directed to a method for deploying an expandable intracorporeal device within a patient's body. The method includes providing a delivery system for delivery of an expandable intracorporeal device including an elongate shaft having a proximal section and a distal section. The distal section of the elongate shaft has an elongate belt support member disposed adjacent a portion of the expandable intracorporeal device and a belt which is secured to the belt support member. The belt is circumferentially disposed about the expandable intracorporeal device and has a configuration that constrains the expandable intracorporeal device. A release member releasably secures the belt in the constraining configuration.
Next, the distal end of the delivery system is introduced into the patient's body and advanced to a desired site within the patient's body. The release member is then activated, releasing the belt from the constraining configuration. Optionally, the delivery system may also have an outer protective sheath disposed about the endovascular graft in a constrained state, the belt in its constraining configuration and at least a portion of the release wire disposed at the belt. In such an embodiment, the method of deployment of an expandable intracorporeal device also includes retraction of the outer protective sheath from the endovascular graft prior to activation of the release member.
In an embodiment of the invention directed to delivery of bifurcated intracorporeal device, an elongate shaft has a proximal section and a distal section. The distal section of the shaft has an elongate primary belt support member and at least one primary belt disposed on the primary belt support member. The primary belt support member is configured to be circumferentially disposed about a bifurcated intracorporeal device and at least partially constrain the device. A primary release member is configured to engage and releasably secure the primary belt in a constraining configuration. At least one elongate secondary belt support member is disposed adjacent the elongate primary belt support member. At least one secondary belt is disposed on the secondary belt support member. This at least one secondary belt is configured to be circumferentially disposed about a bifurcated intracorporeal device and at least partially constrain the device. A secondary release member is configured to engage and releasably secure the secondary belt in a constraining configuration.
In a method for deploying a bifurcated intracorporeal device within a patient's body, a delivery system for delivery and deployment of a bifuircated intracorporeal device is provided. The delivery system includes an elongate shaft having a proximal section and a distal section. The bifurcated intracorporeal device is disposed on the distal section of the elongate shaft. The distal section of the elongate shaft also includes an elongate primary belt support member and at least one primary belt secured to the primary belt support member. The primary belt is configured to be circumferentially disposed about a bifurcated intracorporeal device and at least partially constrain the device. A primary release member engages and releasably secures the primary belt in the constraining configuration. The distal section of the elongate shaft also includes at least one elongate secondary belt support member disposed adjacent the elongate primary belt support member. At least one secondary belt is secured to the secondary belt support member and is configured to be circumferentially disposed about a bifurcated intracorporeal device to at least partially constrain the device. A secondary release member engages and releasably secures the secondary belt in a constraining configuration.
The distal end of the delivery system is introduced into the patient's body and advanced to a desired site within the patient's body. The release members are then activated to release the belts from the constraining configuration and the device is deployed. Thereafter, the delivery system can be removed from the patient's body. In some embodiments of the invention, the secondary belt support member is detached and removed from the delivery system prior to withdrawal of the delivery system from the patient. In another embodiment, the secondary belt support member is displaced laterally towards the primary belt support member so as to be substantially parallel to the primary belt support member and enable withdrawal of the delivery system through an ipsilateral side of the bifurcated intracorporeal device.
BRIEF DESCRIPTION OF THE DRAWINGS
Delivery system 10 in
The endovascular graft 11 has a proximal end 26, a distal end 27, a proximal inflatable cuff 28, a distal inflatable cuff 30, a proximal self-expanding member 31, a first distal self-expanding member 32 and a second distal self-expanding member 33. As defined herein, the proximal end of the elongate shaft is the end 15 proximal to an operator of the delivery system 10 during use. The distal end of the elongate shaft is the end 16 that enters and extends into the patient's body. The proximal and distal directions for the delivery system 10 and endovascular graft 11 loaded within the delivery system 10 as used herein are the same. This convention is used throughout the specification for the purposes of clarity, although other conventions are commonly used. For example, another useful convention defines the proximal end of an endovascular graft as that end of the graft that is proximal to the source of blood flow going into the graft. Such a convention is used in the previously discussed co-pending patent application Ser. No. 09/133,978, although that convention is not adopted herein.
The guidewire tube 17 has an inner lumen 34, as shown in
A portion of the distal section 35 of the guidewire tube 17, shown in
Referring to
Referring to
Referring again to
The belts 21, 22 and 23 can be made from any high strength, resilient material that can accommodate the tensile requirements of the belt members and remain flexible after being set in a constraining configuration. Typically, belts 21, 22 and 23 are made from solid ribbon or wire of a shape memory alloy such as nickel titanium or the like, although other metallic or polymeric materials are possible. Belts 21, 22 and 23 may also be made of braided metal filaments or braided or solid filaments of high strength synthetic fibers such as Dacron®, Spectra or the like. An outside transverse cross section of the belts 21, 22 and 23 may range from about 0.002 to about 0.012 inch, specifically, about 0.004 to about 0.007 inch. The cross sections of belts 21, 22 and 23 may generally take on any shape, including rectangular (in the case of a ribbon), circular, elliptical, square, etc.
In general, we have found that a ratio of a cross sectional area of the belts to a cross sectional area of the release members, 24 and 25, of about 1:2 is useful to balance the relative strength and stiffness requirements. Other ratios, however, may also be used depending on the desired performance characteristics.
The inner diameters of belt bushings 57, 63 and 67 are sized to have a close fit over the guidewire tube 17 and secured portion 71, as shown in
Such an arrangement keeps the self-expanding members 31, 32 and 33 properly situated when in a constrained state and prevents the various portions of the self-expanding members 31, 32 and 33 from overlapping or otherwise entangling portions thereof while in a constrained state. The outer diameter of the belt bushings 57, 63 and 67 may range from about 0.040 inch to about 0.200 inch; specifically, about 0.060 inch to about 0.090 inch. The material of the belt bushings 57, 63 and 67 may be any suitable polymer, metal, alloy or the like that is bondable. Generally, the belt bushings 57, 63 and 67 are made from a polymer such as polyurethane, silicone rubber or PVC plastic.
As shown in
The standoff tubes 72-74 typically have a length substantially equal to a single wall thickness of the self-expanding members 31, 32 and 33. The length of the standoff tubes 72-74 may range from about 0.010 inch to about 0.030 inch. An inner diameter of an inner lumen 75 of the standoff tubes, as shown in
Belts 21-23 exit the outer apertures of standoff tubes 72-74 and extend circumferentially about the respective portions of the expandable intracorporeal device 11. The term “circumferential extension” as used with regard to extension of the belts 21-23 is meant to encompass any extension of a belt in a circumferential direction. The belts may extend circumferentially a full 360 degrees, or any portion thereof. For example, belts or belt segments may extend partially about an endovascular device, and may be combined with other belts or belt segments that also partially extend circumferentially about an endovascular device. Typically, a plane formed by each of the belts 21-23 when in a constraining configuration is generally perpendicular to a longitudinal axis 76, shown in
A single release wire may also be used to perform the function of each of the first and second release wires, 24 and 25, so that first distal belt 21, second distal belt 22, and proximal belt 23 may be releasably secured by a single release wire. A highly controlled, sequential belt deployment scheme may be realized with the use of a single release wire.
Any number of release wires and belts as may be needed to effectively secure and deploy graft 11, in combination, are within the scope of the present invention.
In some embodiments of the invention, when constrained, the end loops of any single belt touch each other or are spaced closely together such that the belt as a whole forms a substantially circular constraint lying substantially in a plane. Release wire 24 and 25 may be made from suitable high strength materials such as a metal or alloy (e.g., stainless steel) which can accommodate the torque force applied to the release wire by the belt end loops 83 when the belts 23 are under tension from the outward radial force of the constrained portions of the endovascular graft 11, i.e., the self-expanding members 32 and 33.
The release wires 24 and 25 may generally have an outer diameter ranging from about 0.006 to about 0.014 inch. Distal end portions 84 and 85 of release wires 24 and 25, respectively, may terminate at any appropriate site distal of the end loops 81-83 of belts 21-23. As shown in
Turning now to
Belts 21C-23C shown in
Alternatively, belts 21C-23C may comprise two strand filaments each wrapped around guidewire tube 17 so that, for instance, belt 21C is a two-filament component.
Belt 21C includes belt arms 112 and 114, each of which, in the embodiments shown, is a loop of filament twisted upon itself to form a helix. Any number of twists may be imparted to arms 112 and 114 to provide a relatively loose or relatively tight helix as desired. Typically the number of twists (with a single twist being defined as a single overlap of wire segment) in each belt arm 112 and 114 numbers from zero to about 50 or more; specifically, about two to about 10. The choice of material used for belt 21C is an important factor in determining the optimum number of twists for each belt arm. Belt arms 112 and 114 may be formed into other configurations (e.g., braid, double helix, etc.) as well.
Disposed within the end loops of the belt arms 112 and 114 are distal apertures or openings 120, 122, respectively. During assembly of the delivery system, a release wire (such as wire 24) is passed through each aperture 120, 122 after the belt arms are wrapped around the graft self-expanding member, preferably in a circumferential groove as further described below. The release wire may also be disposed through any aperture created along the length of belt arms 112, 114 by each helix twist, although the distal-most apertures 120, 122 are preferred.
The wire optionally may be welded, glued, or otherwise fixed to itself at discrete points or along all or any portion of belt arms 112, 114, save their corresponding apertures 120 and 122. For instance, the belt arm wire may be glued or welded to itself at the overlap or twist points, such as points 124.
Belt arm sleeve 126 can be configured to have a transverse dimension that is sized to fit a twisted belt arm with fixed nodal points such as the belt arm 112 shown in
It may be desirable to impart a particular free resting angle to the belt arms 112, 114 to improve the reliability of the system and further reduce the possibility of the arms 112 and 114 interfering with other components of the prosthesis or delivery system. The
All of the features discussed herein with respect to the
This helix configuration shown in the embodiments of
Next, release wire 24 is passed through the portion of aperture 89 that extends beyond this plane so that wire 24 “locks” the two looped ends 81′ and 81″ together as shown. We have found that this is a stable configuration that lends itself well to a reliable and safe deployment protocol.
Other techniques for assembling wire 24 and first and second end loops 81′ and 81″ may be used; the method described above is merely exemplary. Wire 24 may simply pass through loop ends as configured and as shown at reference numerals 81, 82 and 83 in
In the embodiment of
Turning now to
Second belt distal end 118C in
Main portion 152 of the branched release wire 150 engages the proximal belt 23 and has a distal segment 158 that extends distally from the proximal belt 23 to a distal end 161 of the main portion. The length L′ of the distal segment 158 of the main portion 152 is indicated by arrow 162. Length L of distal segment 155 is greater than length L′ of distal segment 158. In this way, as the branched release wire is withdrawn proximally, proximal belt 23 is released first, first distal belt 21 is released second and second distal belt is released last. Such a branched release wire allows a wide variety of belt release timing with a single continuous withdrawal or movement of a proximal end (not shown) of the branched release wire 150. The proximal end of the branched release wire may be terminated and secured to a release wire handle or the like, as discussed herein with regard to other embodiments of release wires. The ability to deploy multiple release wires in a desired timing sequence with a single branched release wire 150 gives the designer of the delivery system great flexibility and control over the deployment sequence while making the deployment of the belts simple and reliable for the operator of the delivery system. Although the branched release wire 150 has been shown with only a single branch, any number of branches or desired configuration could be used to achieve the deployment sequence required for a given embodiment of a delivery system. For example, a separate branch could be used for each belt in a multiple belt system, with varying distal segment length used to control the sequence of deployment. Also, multiple branched release wires, or the like, could be used in a single delivery system to achieve the desired results.
A number of embodiments for the belt and belt arm components of the present invention are described herein. In general, however, we contemplate any belt or belt arm configuration in which the belt may be used to releasably hold or restrain an implant member in conjunction with a release member. The particular embodiments disclosed herein are not meant to be limiting, and other variations not explicitly disclosed herein, such as those in which multiple apertures (which may have varying shapes and sizes) are disposed along the belt length, those in which the belt or belt arm distal ends comprises a separate material or element that is affixed to the belt or belt arm, etc. are within the scope of the invention. Furthermore, various embodiments of the ends of the belts or belt arms taught herein may exist in any combination in a single delivery system.
Turning now to
As shown in
If the end loops 81-83 were to be axially displaced from their normal position relative to the distal ends of the release wires prior to deployment, the timing of the release of the belts 21-23 could be adversely affected. Thus, the prevention of axial displacement of the belts 21-23 during proximal retraction of the release wires 24 and 25 facilitates accurate release of the belts by keeping the overlap joint of the belt looped end portions in a constant axial position during such retraction.
In addition, it may be desirable to keep belts 21-23 positioned at or near the general center of a given constrained self-expanding members 31-33 so that the self-expanding member 31-33 is substantially uniformly and evenly constrained over its axial length. If belts 21-23 constrain the self-expanding members 31-33 at a non-centered axial position on the member, an end of the member opposite that of the non-centered position may be less constrained and may interfere with axial movement of the outer tubular member 53 (and consequently deployment of the endovascular graft 11).
Tubular body member 205 of the endovascular graft 11 is disposed between and secured to the second distal self-expanding member 33 and the proximal self-expanding member 31. The tubular body member comprised of flexible material 204, is shown constrained in an idealized view in
An inner tubular member 207 is slidably disposed within the inner lumen 52 of outer tubular member 53. Release wires 24 and 25, guidewire tube 17 and an inflation tube 211 are disposed within an inner lumen 212 of the inner tubular member 207. Inner lumen 212 is optionally sealed with a sealing compound, depicted in
In
Turning to
A similar configuration exists for the proximal end 87 of the second release wire 25. There, a second release wire side arm 226 branches from the proximal adapter body portion 233 and has an inner lumen 244 that houses the proximal end 87 of the second release wire 25 which is free to slide in an axial orientation within the lumen 244. A proximal extremity 246 of the second release wire 25 is configured as an expanded bushing or other abutment that captures the second release wire handle and translates axial proximal movement of the second release wire handle 94 to the second release wire 25, but allows relative rotational movement between the proximal end 87 of the second release wire 25 and the second release wire handle 94.
The first release wire handle 93 and second release wire handle 94 may optionally be color coded by making each, or at least two, release wire handles a color that is distinctly different from the other. For example, the first release wire handle 93 could be made green in color with the second release wire handle 94 being red in color. This configuration allows the operator to quickly distinguish between the two release wire handles and facilitates deployment of the belts in the desired order.
In another embodiment, instead of color coding of the release wire handles 93 and 94, the spatial location of the handles can be configured to convey the proper order of deployment of the release wires to the operator of the delivery system. For example, if three release wire handles are required for a particular embodiment, the corresponding three side arms can be positioned along one side of the proximal adapter. In this configuration, the release wire handle that needs to be deployed first can extend from the distal-most side arm. The release wire handle that needs to be deployed second can extend from the middle side arm. The release wire handle that is to be deployed last can extend from the proximal-most side arm. For such a configuration, the operator is merely instructed to start deployment of the release wires at the distal-most release wire handle and work backward in a proximal direction to each adjacent release wire handle until all are deployed. Of course, an opposite or any other suitable configuration could be adopted. The configuration should adopt some type of spatially linear deployment order, either from distal to proximal or proximal to distal, in order to make reliable deployment of the release wires in the proper order easy to understand and repeat for the operator of the delivery system. Other types of release order indicators such as those discussed above could also be used, such as numbering each release wire handle or side arm with a number that indicates the order in which that handle is to be deployed.
The proximal end 36 of the guidewire tube 17 terminates and is secured to an inner lumen 251 of the proximal end 259 of the proximal adapter 42. Inner lumen 251 typically has a longitudinal axis 253 that is aligned with a longitudinal axis 254 of the proximal section 13 elongate shaft 12 so as to allow a guidewire to exit the proximal end 15 of the elongate shaft 12 without undergoing bending which could create frictional resistance to axial movement of the guidewire. A proximal port 255 of the proximal adapter 42 may be directly fitted with a hemostasis valve, or it may be fitted with a Luer lock fitting which can accept a hemostasis valve or the like (not shown).
The proximal adapter 42 may be secured to the proximal end 215 of the inner tubular member 207 by adhesive bonding or other suitable method. A strain relief member 256 is secured to the distal end 257 of the proximal adapter 42 and the inner tubular member 207 to prevent kinking or distortion of the inner tubular member 207 at the joint.
As seen in
When the outer tubular member 53 is positioned on the proximal shoulder 48 of the distal nose piece 44 prior to deployment of endovascular graft 11, the distance between a proximal extremity 267 of proximal fitting 262 and a distal extremity 268 of stop 266 is approximately equal to or slightly greater than an axial length of the endovascular graft 11 in a constrained state. This configuration allows the outer tubular member 53 to be proximally retracted to fully expose the endovascular graft 11 in a constrained state prior to deployment of the graft. This distance may be greater, but should not be less than the length of the endovascular graft 11 in a constrained state in order to completely free the constrained graft 11 for radial expansion and deployment.
Retraction limiters may alternatively be used to prevent excessive axial movement of the release wires 24 and 25 in a proximal direction during deployment. Particularly in embodiments of the invention where single release wires are used to constrain and deploy multiple belts such as with first release wire 24, retraction limiters may be used to allow enough axial movement of the release wire 24 to deploy a first belt 21, but prevent deployment of a second more proximally located belt 22. For example, as shown in
In use, the delivery system 10 is advanced into a patient's arterial system 271 percutaneously as shown in
Generally, the position of the delivery system 10 is determined using fluoroscopic imaging or the like. As such, it may be desirable to have one or more radiopaque markers (not shown) secured to the delivery system at various locations. For example, markers may be placed longitudinally coextensive with the respective distal and proximal extremities 274 and 275, as shown in
Once the distal section 14 of the delivery system 10 is properly positioned within the patient's artery 45, the operator moves the proximal end 261 of outer tubular member 53 in a proximal direction relative to inner tubular member 207. The relative axial movement is carried out by grasping the proximal end 215 of the inner tubular member 207 or proximal adapter 42, and grasping the proximal end 261 of the outer tubular member 53, and moving the respective proximal ends towards each other. This retracts the distal section 276 of the outer tubular member 53 from the constrained endovascular graft 11 and frees the graft for outward radial expansion and deployment. However, in this deployment scheme, note that the operator is free to reinsert graft 11 back into the outer tubular member 53 if necessary, as the release bands have not yet released the graft.
Once the distal section 276 of the outer tubular member 53 has been retracted, handle 93 of the first release wire 24 may then be unscrewed or otherwise freed from the proximal adapter 42 and retracted in a proximal direction indicated by arrow 279 in
If the operator of the delivery system 10 is not satisfied with the position, particularly the axial position, of the endovascular graft 11 after deployment of the first distal self-expanding member 32, it may then be possible to re-position the endovascular graft 11 by manipulating the proximal end 15 of the elongate shaft 15. Movement of the elongate shaft 12 can move the endovascular graft 11, even though physical contact between the expanded member 32 and the vessel inner surface 278 generates some static frictional forces that resist such movement. It has been found that the endovascular graft 11 can be safely moved within a blood vessel 45 even in the state of partial deployment discussed above, if necessary.
Once the operator is satisfied with the position of the graft 11, the first release wire 24 may then be further proximally retracted so as to deploy the second distal belt 22 in a manner similar to the deployment of the first distal belt 21. The deployment of the second distal belt 22 occurs when the distal end 84 of the first release wire 24 passes from within end loops 82 of the second distal belt 22 which are held in a radially constraining configuration by the first release wire 24. Upon release of the second distal belt 22, the second distal self-expanding member 33 expands in a radial direction such that it may engage inner surface 278 of the patient's aorta 45. The amount of outward radial force exerted by the self-expanding members 32 and 33 on the inside surface 278 of the patient's aorta 45, which may vary between members 32 and 33, is dependent upon a number of parameters such as the thickness of the material which comprises the self-expanding members 32 and 33, the nominal diameter which the self-expanding members 32 and 33 would assume in a free unconstrained state with no inward radial force applied, material properties of the members and other factors as well.
Once the distal members 32 and 33 are deployed, the handle 94 for the second release wire 25 can be disengaged and axially retracted in a proximal direction from the proximal adapter 42 until the distal end 85 of the second release wire 25 passes from within the end loops 83 of the proximal belt 23. Once the proximal belt 23 is released, the proximal self-expanding member 31 is deployed and expands in an outward radial direction, such that it may engage or be in apposition with the inner surface 278 of the patient's aorta 45 as shown in
Before or during the deployment process, and preferably prior to or simultaneous with the step of inflating the endovascular graft 11, it may be beneficial to optionally treat vessel 45 in which the graft 11 is deployed so to obtain a better seal between the graft 11 and the vessel inner surface 278, thus improving the clinical result and helping to ensure a long term cure.
One approach to this treatment is to administer a vasodilator, or spasmolytic, to the patient prior to deploying graft 11. This has the effect of reducing the tone of the smooth muscle tissue in the patient's arteries; specifically, the smooth muscle tissue in the wall of vessel 45 into which graft 11 is to be deployed. Such tone reduction in turn induces the dilation of vessel 45, reducing the patient's blood pressure. Any number of appropriate vasoactive antagonists, including the direct acting organic nitrates (e.g., nitroglycerin, isosorbide dinitrate, nitroprusside), calcium channel blocking agents (e.g., nifedipine), angiotensin-converting enzyme inhibitors (e.g., captopril), alpha-adrenergic blockers (e.g., phenoxybenzamine, phentolamine, prasozin), beta-adrenergic blockers (e.g., esmolol) and other drugs may be used as appropriate. Particularly useful are those vasodilators that can be administered intravenously and that do not have unacceptable contraindications such as aoritic aneurysm dissection, tachycardia, arrhythmia, etc.
The degree of vasodilatation and hypotensive effect will depend in part on the particular vessel in which graft 11 is to be placed and the amount of smooth muscle cell content. Generally, the smaller the vessel, the larger percentage of smooth muscle cell present and thus the larger effect the vasodilator will have in dilating the vessel. Other factors that will effect the degree of vasodilatation is the health of the patient; in particular, the condition of the vessel 11 into which graft 11 is to be placed.
In practice, once the vasodilator has been administered to the patient, graft 11 may be deployed and filled with inflation material so that graft 11 reaches a larger diameter than would otherwise be possible if such a vasodilator was not used. This allows the inflation material to expand the diameter of graft 11, for a given inflation pressure, beyond that which would be achievable if the vessel 45 were in a non-dilated state (and nominal diameter). Alternatively, a larger diameter graft 11 may be chosen for deployment. We anticipate that an increased vessel diameter of between two and twenty percent during vasodilatation may be optimal for achieving an improved seal.
The vessel 45 in which graft 11 is to be placed may optionally be monitored pre- and/or post-dilation but before deployment of graft 11 (via computed tomography, magnetic resonance, intravenous ultrasound, angiography, blood pressure, etc.) so to measure the degree of vasodilatation or simply to confirm that the vasodilator has acted on the vessel 45 prior to deploying graft 11.
Once the vasodilator wears off, preferably after between about five and thirty minutes from the time the drug is administered, the vessel 45 surrounding graft 11 returns to its normal diameter. The resultant graft-vessel configuration now contains an enhanced seal between graft 11 and vessel inner surface 278 and provides for reduced luminal intrusion by graft 11, presenting an improved barrier against leakage and perigraft blood flow compared to that obtainable without the sue of vasodilators or the like.
Such vasodilating techniques may be used with all of the embodiments of the present invention, including the tubular graft 11 as well as a bifurcated graft version of the expandable intracorporeal device of the present invention as is discussed in detail below.
Once graft 11 is fully deployed, a restraining or retention device, such as retention wire 285 that binds the distal end 286 of the inflation tube 111 to the inflation port 283, as shown in
Referring to
The proximal adapter 323 has a first side arm 324 with an inner lumen 325 that secures the proximal end 321 of the release wire tube 318. A threaded end cap 326 is secured to a proximal end 327 of the first side arm 324 and has a threaded portion 328. A second release wire handle 331, having a distal threaded portion 332 and a proximal threaded portion 333, is threaded onto the threaded end cap 326. A proximal end 334 of the second release wire 316 is secured to the second release wire handle 331. A first release wire handle 335 has a threaded portion 336 that is releasably threaded onto the proximal threaded portion 333 of the second release wire handle 331. A proximal end 337 of the first release wire 312 is secured to the first release wire handle 335.
Once the outer tubular member 53 has been proximally retracted, belts 21-23 can be released. This configuration allows the operator of the delivery system 300 to first disengage and proximally retract the first release wire handle 335 so as to first release the second distal self-expanding member 33 without releasing or otherwise disturbing the constrained state of the first distal self-expanding member 32 or the proximal self-expanding member 31. Once the second distal self-expanding member 33 has been deployed or released, the endovascular graft 11 may be axially moved or repositioned to allow the operator to adjust the position of the graft 11 for final deployment.
This is advantageous, particularly in the treatment of abdominal aortic aneurysms, because it allows the physician to accurately place graft 11 into position. In many cases, it is desirable for the physician to place the graft 11 such that the distal end of the tubular body portion 205 of the graft is just below the renal arteries 273, shown in
Thereafter, the second release wire handle 331 may be unscrewed or otherwise released from the end cap 326 and proximally retracted so as to first release the first distal belt end loops 81 and then the proximal belt end loops 83. Of course, the position of the graft 11 may still be adjustable even with both distal self-expanding members 32 and 33 deployed, depending on the particular configuration of the graft 11 and the self-expanding members 32 and 33. The release of the belts 21, 22 and 23 is the same or similar to that of the belts of the embodiment of
Once the self-expanding members 31-33 of the endovascular graft 11 have been deployed or released, and the graft 11 is in a desired location, the graft 11 can then be inflated by injection of an inflation material (not shown) into the injection port 338 on a second side arm 341 of the proximal adapter 323. The inflation material is introduced or injected directly into an inner lumen 212 of the inner tubular member 207, as shown in
Once the inflation material, which is travelling distally in the delivery system 300 during inflation, reaches the potted portion 213 of the distal section 303 of the delivery system, it then enters and flows through a lumen 344, as shown in
A proximal end 36 of the guidewire tube 17 is secured within a central arm 345 of the proximal adapter 323 that has a potted section 346. A seal 349 is disposed on a proximal end 347 of the central arm 345 for sealing around the guidewire 18 and preventing a backflow of blood around the guidewire. A hemostasis adapter (not shown) can be coupled to the proximal end 347 of the central arm 345 in order to introduce fluids through the guidewire tube lumen 348, as shown in
In use, the operator first unscrews or otherwise detaches a threaded portion 363 of the first release wire handle 361 from an outer threaded portion 364 of a first side arm end cap 365 of a first side arm 366. The first release wire handle 361 is then proximally retracted which releases the end loops 82 of the second distal belt 22 as discussed above with regard to the embodiment of the invention shown in
Once the first release wire handle 361 is removed from the first side arm end cap 365, the second release wire handle 362 is exposed and accessible to the operator of the delivery system. A threaded portion 367 of the second release wire handle 362 can then be unscrewed or otherwise detached from an inner threaded portion 368 of the first side arm end cap 365. The second release wire handle 362 can then be retracted proximally so as to sequentially deploy the first distal belt 21 and self-expanding member 32 and proximal belt 23 and proximal self-expanding member 31, respectively. The other functions and features of the proximal adapter 360 can be the same or similar to those of the proximal adapters 42 and 323 shown in
Optionally, this embodiment may comprise reverse or oppositely threaded portions, 363 and 367 respectively, of the first and second release wire handles 361 and 362. Thus, for instance, a counter-clockwise motion may be required to unthread threaded portion 363 of the first release wire handle 361 from the outer threaded portion 364, while a clockwise motion is in contrast required to unthread threaded portion 367 of the second release wire handle 367 from the inner threaded portion 368. This feature serves as a check on the overzealous operator who might otherwise prematurely unscrew or detach the threaded portion 367 of the second release wire handle 362 by unscrewing in the same direction as required to release the threaded portion 363 of the first release wire handle 361.
In another aspect of the invention, a delivery system 400 for delivery and deployment of a bifurcated intracorporeal device, specifically, an embodiment of the invention directed to delivery and deployment of a bifurcated endovascular graft or stent is contemplated. As with all the delivery systems disclosed herein, the delivery system 400 for a bifurcated device is configured for delivery and deployment a wide variety of intracorporeal devices. Although the focus of the specific embodiments are directed to systems for delivery of endovascular grafts or stent grafts, embodiments of the delivery systems disclosed herein can are also suitable for delivery of intravascular filters, stents, including coronary stents, other types of shunts for intracorporeal channels, aneurysm or vessel occluding devices and the like.
The structure, materials and dimensions of the delivery system 400 for bifurcated devices can be the same or similar to the structure, materials and dimensions of the delivery systems discussed above. In addition, the structure, materials and dimensions of bifurcated grafts contemplated herein can have structure, materials and dimensions similar to those of grafts having a primarily tubular shape discussed above.
The main body portion 402 of the graft may have a transverse dimension when in an expanded or deployed state ranging from about 10 mm to about 40 mm, specifically from about 15 mm to about 30 mm. The legs 404 and 405 of the graft 401 may have a transverse dimension when in an expanded or deployed state ranging from about 5 mm to about 16 mm, specifically from about 8 mm to about 14 mm. The main body portion 402 of the graft 401 may have a length ranging from about 2 cm to about 12 cm, specifically from about 4 cm to about 8 cm.
A second distal self-expanding member 411 is disposed at a distal end 412 of the main body portion 402 of the graft 401 as with the graft embodiments previously discussed. Also, as with other endovascular graft embodiments discussed herein, the graft 401 may have inflatable channels and inflatable cuffs that serve, among other functions, to provide support for the graft 401 and the inflatable channels and cuffs can have configurations which are the same or similar to those inflatable channels and cuffs of other graft embodiments discussed herein, as well as other configurations. A distal inflatable cuff 413 is disposed at the distal end 412 of the main body portion 402. Proximal inflatable cuffs 414 and 415 are disposed on a proximal end 416 of the ipsilateral leg 404 and a proximal end 417 of the contralateral leg 405 respectively. Inflatable channels 418 are fluid tight conduits which connect the inflatable cuffs 413, 414 and 415. The inflatable channels 418 and inflatable cuffs 413 and 414 are inflatable through an inflation port 421 that may be disposed at or near the proximal end 416 of the ipsilateral leg 404. The inflation port 421 may also be disposed at or near the proximal end 417 of the contralateral leg 405, or it may be disposed on other portions of the device as necessary. Generally, the structure and the materials used in the graft 401 (both the graft portion and the self-expanding members) can be similar to the structure and materials of the other graft embodiments discussed above. In one particular embodiment, the main body portion and legs of the graft are made of expanded polytetrafluoroethylene (ePTFE) and the self-expanding members are made of nickel titanium, stainless steel or the like.
A first distal self-expanding member 422 is secured to the second distal self-expanding member 411 as shown in
In addition, although not shown in the figures, this graft embodiment 401 may include two or more proximal self-expanding members disposed on one or both of the ipsilateral leg 404 and/or contralateral leg 405. These self-expanding members may have a configuration similar to that of the first and second distal self-expanding members 411 and 422
Bifurcated stent graft 401 is shown in
A release member tube in the form of a release wire tube 441 is disposed about a distal primary release member in the form of a distal primary release wire 442. The release wire tube 441 is also disposed about a proximal primary release member in the form of a proximal primary release wire 443. Both the release member tube 441 and an inflation tube 444 are disposed within an inner lumen 445 of the inner tubular member 430. The outside diameter of the release wire tube 441 may range from about 0.01 inch to about 0.05 inch, specifically about 0.015 inch to about 0.025 inch. The wall thickness of the release wire tube 441 may range from about 0.001 inch to about 0.006 inch, specifically from about 0.002 inch to about 0.004 inch.
The outside diameter of the inflation tube 444 may range from about 0.02 inch to about 0.10 inch; specifically from about 0.04 inch to about 0.08 inch. The inflation tube 444 wall thickness may range from about 0.002 inch to about 0.025 inch; specifically from about 0.003 inch to about 0.010 inch.
In
A more detailed view of the distal section 426 of the elongate shaft 423 is shown in partial section in
The secondary belt support member housing lumen 455 and secondary support member 454 cross sections may be keyed, singly or in combination, to allow relative sliding motion without relative rotation motion and therefore limit any twisting of the secondary support member 454 and the contralateral leg 405. The secondary belt support member 454 may be made from alloys such as nickel titanium, stainless steel, or polymeric materials such as polyimide and can have an outside transverse dimension ranging from about 0.01 inch to about 0.06 inch.
A proximal primary belt 456 is shown in
A first distal primary belt 458 is disposed about and radially constraining the first distal self-expanding member 422, which itself is disposed about a cylindrical bushing 461. A second distal primary belt 462 is disposed about and radially constraining the second distal self-expanding member 411 and the second distal self-expanding member 411 is disposed about a cylindrical bushing 463.
A secondary belt 464 is shown disposed about and radially constraining the proximal self-expanding member 408 of the contralateral leg 405. This proximal self-expanding member 408 is disposed about a bushing 465 that is cylindrical in shape.
As with the other embodiments of the present invention, the belts 456, 458, 462 and 464 are typically made from nickel titanium, an alloy that is capable of exhibiting a unique combination of high strain without elastic deformation, high strength and biocompatability. However, any other suitable materials may be used including other metallic alloys such as stainless steel, high strength fibers such as carbon, KEVLAR®, polytetrafluoroethylene (PTFE), polyimide, or the like. The outer transverse dimension or diameter of the belts 456, 458, 462 and 464 can be from about 0.002 inch to about 0.012 inch; specifically about 0.004 inch to about 0.007 inch.
A distal portion 466 of the proximal primary release wire 443 is disposed within end loops 468 of the proximal primary belt 456 so as to releasably secure the proximal self-expanding member 407 of the ipsilateral leg 404 in a constrained state. The proximal primary belt 456 may be disposed about the self-expanding member 407 in a hoop-like configuration. The proximal self-expanding member 407 exerts outward radial pressure on the releasably secured belt 456. The primary proximal release wire 443 is axially moveable within the end loops 468 of the proximal primary belt 456 to allow for release of the belt by proximal retraction of the primary proximal release wire 443 in the same manner as described above with respect to other embodiments of the present invention.
Likewise, a distal portion 471 of the distal primary release wire 442 is disposed within end loops 472 of the second distal primary belt 462 that radially constrains the second distal self-expanding member 411. The second distal primary belt 462 is formed in a hoop configuration about the second distal self-expanding member 411 and the second distal self-expanding member 411 exerts outward radial force on the second distal primary belt 462. The distal primary release wire 442 is axially moveable within the end loops 472 of the second distal primary belt 462 to allow for release of the radial constraint as discussed above with respect to the proximal primary release wire 443 and as discussed above for other embodiments of the present invention. The distal portion 471 of the distal primary release wire 442 is also disposed within end loops 473 of the first distal primary belt 458 and radially constrains the first distal self-expanding member 422 in a similar fashion.
Although the distal primary release wire 442 and proximal primary release wire 443 are shown as two separate components, the release wires 442 and 443 could be combined into a single release member, such as the branched release wire 150 shown in
A distal portion 474 of a secondary release member in the form of a secondary release wire 475 is disposed within end loops 476 of a secondary belt 464 that radially constrains the proximal self-expanding member 408 of the contralateral leg 405. The proximal self-expanding member 408 of the contralateral leg 405 exerts outward radial force on the secondary belt 464 when the self-expanding member 408 is in a constrained configuration. The secondary release wire 475 is axially moveable within the end loops 476 of the secondary belt 464.
A proximal end 477 of the secondary release wire 475 is secured to an actuator hub 478. A release strand 481 is secured to the actuator hub 478 and is attached to the secondary belt support member 454, and is shown by way of example in the embodiment of
As discussed above with respect to other embodiments, the release wires 442, 443 and 475 are generally made from a biocompatible high strength alloy such as stainless steel, but can also be made from any other suitable materials. Examples include other metallic alloys such as nickel titanium, non-metallic fibers such as carbon, polymeric materials, composites thereof, and the like. As discussed above, the diameter and stiffness of the release wires 442, 443 and 475 can be important with respect to the diameter and stiffness of the belts 456, 458, 462 and 464.
The configuration of the end loops 468, 472, 473 and 476 of the belts 456, 458, 462 and 464 may vary to suit the particular embodiment of the delivery system 400 and device to be delivered. For example,
Inflation port 421 extends proximally from the proximal end 416 of the ipsilateral leg 404 of the graft 401. The inflation port 421 is coupled to a distal end 487 of the inflation tube 444 by a retention mechanism, such as a retention wire 488, the operation of which can be the same or similar to like embodiments of retention wire 285 discussed above. Typically, the retention wire 488 extends from the inflation port 421 proximally to the proximal adapter 427 of delivery system 400. The distal end 487 of the inflation tube 444 can be disengaged from the inflation port 421 by pulling on a proximal end 491 of retention wire 488, as shown in
A proximal end 501 of the guidewire tube 436 is secured within a central arm 502 of the proximal adapter 427 that has a potted section 503. A seal 504 may be disposed on a proximal end 505 of the central arm 502 for sealing around the guidewire lumen and preventing a backflow of fluid. The potted section 503 of the central arm 502 prevents any injected fluids from passing into the inflation material lumen 506 within the proximal adapter 427 or the inner tubular member 430. The other functions and features of the proximal adapter 427 may be the same or similar to those of the proximal adapters 42 and 323 shown in
In general, the various features and components (including, e.g., details of various embodiments of the release wires, the self-expanding members, belts, inflation port and tube, guidewire tube, standoff tubes, proximal adapter and its associated components, the materials and dimensions for each of the various components, etc.) as discussed herein with respect to those embodiments of
In use, the delivery system 400 for delivery of a bifurcated intracorporeal device, specifically, a bifurcated graft 401, can be operated in a similar fashion to the delivery systems discussed above.
One delivery procedure of the present invention begins with delivery of a first guidewire 530 into an access hole 531 in a femoral artery, the right femoral artery 532 for the procedure depicted in
With the first guidewire 530 positioned across the aneurysm 518, a second guidewire 534 is then introduced into the ipsilateral or right femoral artery 532 and guided into the iliacs 517 and then back down into the contralateral or left femoral artery 533 as shown in
Once the second guidewire 534 exits the access hole 537 in the left femoral artery 533, a tubular catheter 538 may be advanced over the second guidewire 534 through the left femoral artery access hole 537 so as to extend out of the body from the access hole 531 in the right femoral artery 532 as shown in
The second guidewire 534 is then pulled out of the tubular catheter 538 from the left femoral artery access hole 537, in the direction indicated by the arrow 544 in
The delivery system 400 is then advanced into the patient's right femoral artery 532 through the access hole 531 over the first guidewire 530 as shown in
FIGS. 37A-B show an optional marker band that may disposed adjacent nosepiece 434 or generally in the vicinity of the distal end of the delivery system 425. Such a marker band 551 may also be integral with the delivery system 400; for example, it may be incorporated as part of the distal nosepiece 434. A useful marker 551 can be one that does not add to the profile of the delivery system 400 as shown in
For example, the marker embodiment 551 of
The embodiment 554 of
For each of the embodiments of FIGS. 37A-B, variations in the shape, number, orientation, pattern and location of the notch 553 and 555, holes 556 or other discontinuity, as well as various marker body dimensions cross sectional shape, etc., may be realized, as long as the marker 551 and 554 is configured so that the angular orientation of the delivery system 400 may readily be determined by the user under fluoroscopy or similar imaging technique.
The delivery system 400 is positioned in a location suitable for initiating the deployment process, such as one in which the distal end 425 of the delivery system 400 is disposed beyond, or distal to the position in which the graft 401 will be placed, as shown in
Once the distal section 426 of the elongate shaft 423 and the endovascular graft 401 are positioned, the deployment process is initiated. First, the outer tubular member 431 is proximally retracted by pulling on the proximal end 433 of the outer tubular member 431 relative to the inner tubular member 430. The inner tubular member 430 should be maintained in a stable axial position, as the position of the inner tubular member 430 determines the position of the constrained bifurcated graft 401 prior to deployment. Upon retraction of the outer tubular member 431, the constrained bifurcated graft 401 is exposed and additional slack is created in the secondary release cable 438 as shown in more detail in
Alternatively, a variety of different components may be substituted for the outer tubular member 431 in some of the embodiments of the invention. For instance, a shroud, corset, mummy-wrap, or other cover may be released or actuated to expose the constrained graft 401 after the delivering system 400 is introduced into the vasculature.
The slack in the secondary release cable 438 is taken up by applying tension to both lengths 561 and 562 of the release strand 481 as shown by the arrows 563 in
Axial compression of all or a portion of the contralateral leg 405 while the graft 401 is in a constrained state within the delivery system 400 prior to deployment allows the axial position of the two proximal self-expanding members 407 and 408 to be axially offset from each other. Alternatively, graft legs 404 and 405 having different lengths may be used to prevent overlap of the self-expanding members 407 and 408 within the delivery system 400. The cross sectional profile or area of the overlap self-expanding members 407 and 408 is generally greater than that of the adjacent polymer material portion of the legs 404 and 405 of the graft 401, so eliminating the overlap can be desirable. The self-expanding members 407 and 408 are typically made of a metal or metallic alloy and maintain a cylindrical configuration, even when in a constrained state. The polymer material of the legs 404 and 405 or main body portion 402 of the graft 401, by contrast, is relatively soft and malleable and can conform to the shape of whatever lumen in which it may be constrained. Placing both proximal self-expanding members 407 and 408 adjacent each other in a compressed state at a single axial position within the delivery system 400 would require a configuration in which two objects having an approximately circular cross section are being placed within another circular lumen. Such a configuration generates a significant amount of wasted or unused cross sectional area within that axial position of the delivery system 400 and would likely result in less flexibility and greater cross section than a delivery system 400 in which the proximal self-expanding members 407 and 408 are axially offset.
A gap 566 indicated by the arrows 567 in
The lateral movement of the contralateral leg 405 and secondary belt support member 454 is accomplished by application of tension on both lengths 561 and 562 of the release strand 481 as shown by the arrows 571 in
Once the ipsilateral leg 404 of the graft 401 and contralateral leg 405 of the graft 401 are aligned with the right and left iliac arteries 572 and 573, respectively, the delivery system 400 may then be retracted proximally, as shown by the arrow 574 in
As discussed above with respect to placement of a tubular graft 11 embodiment of the present invention, when deploying the graft 401 in the abdominal aorta 516 it is generally desirable to ensure that the distal end 403 of the graft main body portion 402 is installed proximal to, or below, the renal arteries 519 in order to prevent their significant occlusion. However, the distal self-expanding members 411 and 422 of the graft 401 may, depending upon the anatomy of the patient and the location of the aneurysm 518, partially or completely span the ostia 575 of one or both renal arteries 519. It can be desirable, however, to ensure that ostia 575 of the renal arteries 519 are not blocked by the distal end 403 of the graft main body portion 402. As discussed previously, a variety of imaging markers 551 and 554 may be used on either or both the delivery system 400 and the graft 401 itself to help guide the operator during the graft positioning process.
After proper positioning, the first and second distal self-expanding members 411 and 422 may then be deployed. The operator first unscrews or otherwise detaches a threaded portion 576 of the distal primary release wire handle 495 from an outer threaded portion 577 of a first side arm end cap 578 shown in
As the first and second distal self-expanding members 411 and 422 expand and contact the aorta 516, a distal end 403 of the graft main body portion 402 opens with the self-expanding members 411 and 422 and promotes opening of the graft polymer material portion from the flow of blood into the distal end 403 of the graft main body portion 402 with a “windsock” effect. As a result, once the first and second distal self-expanding members 411 and 422 are expanded to contact the aorta inner surface 583, the graft main body portion 402 and legs 404 and 405 balloon out or expand while the proximal ends 416 and 417 of the legs 404 and 405 of the graft 401 remain constricted due to the constrained configuration of the proximal self-expanding members 407 and 408 of the ipsilateral and contralateral legs 404 and 405, as shown in
Bifurcated graft 401 may then be optionally be inflated with an inflation material via inflation tube 444 and inflation port 421 until the inflatable channels 418 and inflatable cuffs 413, 414 and 415 have been filled to a sufficient level to meet sealing and other structural requirements necessary for the bifurcated graft main body portion 402 and the ipsilateral and contralateral legs 404 and 405 to meet clinical performance criteria. As described in later conjunction with an alternative embodiment of the present invention, inflating the graft 401 prior to deploying the proximal and distal self-expanding members 407 and 408, respectively, is useful in anatomies where the vasculature is tortuous or angled.
Next, the proximal self-expanding member 407 of the ipsilateral leg 404 is deployed. Deployment of the first and second distal self-expanding member 411 and 422 has exposed the proximal primary release wire handle 496, making it accessible to the operator. A threaded portion 584 of the proximal primary release wire handle 496 is unscrewed or otherwise detached from an inner threaded portion 585 of the first side arm end cap 578. The proximal primary release wire handle 496 may then be retracted proximally so as to deploy the proximal primary belt 456 and proximal self-expanding member 407 of the ipsilateral leg 404 as shown in
When both a first length 561 and second length 562 of the release strand 481 are pulled together in a proximal direction from a proximal end 588 of the secondary release cable 438, the entire pulling force is exerted on the proximal end 483 of the secondary belt support member 454 because the looped distal end 542 of the release strand 481 pulls on the proximal end 483 of the secondary belt support member 454 without displacing the actuator hub 478.
When deployment of the proximal self-expanding member 408 of the contralateral leg 405 is desired, the operator applies tension in a proximal direction only to the first length 561 of the release strand 481, which extends proximally from the actuator hub 478. The direction of such tension is indicated in
In another configuration (not shown), a similar retention or latch wire 603 passes through aligned aperatures in the secondary belt support member 454 and a housing, such as secondary belt support member housing 453 of
If not previously filled, the bifurcated graft 401 may thereafter be inflated with an inflation material described with respect to the tubular graft embodiment 11.
For all the embodiments described, both tubular and bifurcated, inflation is generally accomplished by inserting or injecting, via one or more device such as a syringe or other suitable mechanism, the inflation material under a pressure- or volume-control environment.
For instance, in one embodiment of a pressure-control technique, a volume of inflation material is first injected into the delivery system 400 (which at this point may include the graft, but may also include the inflation tube 444). The particular desired volume of inflation material will depend on several factors, including, e.g., the composition and nature of the inflation and polymer graft material, the size of the graft 401 to be deployed, the vessel or lumen diameter into which the graft 401 is deployed, the configuration of the graft 401 (tubular, bifurcated, etc.), the features of the graft main body 402 and (if present) legs 404 and 405, and the conditions during the procedure (such as temperature).
Thereafter, the operator may affix a pressure control device, such as an inflation syringe, to the injection port 621 of the proximal adapter 427 of the inflation tube and apply a pressure to the delivery system 400 and a graft 401 for a period of time. This serves to ensure that the fill material previously introduced enters the graft 401 and fills it to the desired pressure level.
We have found that a useful pressure-control approach involves a series of such constant pressure applications, each for a period of time. For instance, the graft 401 may first be pressurized at a level from about 5 psi to about 12 psi or higher, preferably about 9 psi, for between about 5 seconds and 5 minutes, preferably about 3 minutes or more. Optional monitoring of the fluid and the device during the fill procedure may be used to help ensure a proper fill. Such monitoring may be accomplished under fluoroscopy or other technique, for instance, if the fill material is radiopaque.
Thereafter, the fill protocol may be completed, or the pressure may be increased to between about 10 psi and about 15 psi or higher, preferably about 12 psi, for an additional period of time ranging from between about 5 seconds and 5 minutes or more, preferably about 1 minute. If the graft 401 so requires, the pressure may be increased one or more additional times in the same fashion to effect the proper fill. For instance, subsequent pressure may be applied between about 12 and 20 psi or more, preferably about 16 psi to 18 psi, for the time required to satisfy the operator that the graft 401 is sufficiently filled.
The details of particular pressure-time profiles, as well as whether a single pressure-time application or a series of such applications is used to fill embodiments of the graft 401 will depend on the factors described above with respect to the volume of fill material used; the properties and composition of the fill material tend to be of significance in optimizing the fill protocol. For example, a stepped series of pressure-time profiles as described above is useful when the fill material comprises a hardenable or curable material whose physical properties may be time-dependent and which change after being introduced into the graft 401 and its delivery system 400.
Alternatively, a volume-control method may be utilized to fill embodiments of the grafts 11 and 401, including both tubular and bifurcated. Here, a volume of fill material is again introduced into the delivery system 400 as described above. In this method, however, the volume of fill material used is precisely enough material to fill the graft 401, the inflation tube 444, and any other component in the delivery system 400 through which the fill fluid may travel on its way to the graft 401. The operator introduces the predetermined quantity of fill material, preferably with a syringe or similar mechanism, into the inflation tube 444 and graft 401. A precise amount of fill material may be measured into a syringe, for example, so that when the syringe is emptied into the delivery system 400 and graft 401, the exact desired amount of fill material has reached the graft 401. After a period of time (which period will depend on the factors previously discussed), the syringe or equivalent may be removed from the inflation tube 444 or injection port 621 of proximal adapter 427 and the procedure completed.
A pressurized cartridge of gas or other fluid may be used in lieu of a syringe to introduce the fill material into the delivery system and graft under this volume-control regime so to provide a consistent and reliable force for moving the fill material into the graft 401. This minimizes the chance that variations in the force and rate of fill material introduction via a syringe-based technique affect the fill protocol and possibly the clinical efficacy of the graft 401 itself.
For each of the pressure- and volume-control configurations, an optional pressure relief system may be included so to bleed any air or other fluid existing in the delivery system 400 prior to the introduction of the fill material (such as the inflation tube 444 or graft 401) so to avoid introducing such fluid into the patient. Such an optional system may, for example, comprise a pressure relief valve at the graft 401/inflation tube 444 interface and a pressure relief tube disposed through the delivery system 400 (e.g., adjacent the inflation tube 444) terminating at the proximal adapter 427 and vented to the atmosphere.
When graft 401 is deployed in certain anatomies, such as those where the iliac arteries are tortuous or otherwise angled, the lumen of one or more of graft inflatable cuffs 413, 414 and 415 and channels 418 of may become pinched or restricted in those portions of the graft 401 experiencing a moderate or high-angle bend due to the tortuosity of the vessel into which that portion of graft 401 is deployed. This reduction or even elimination of cuff/channel patency can hinder and sometimes prevent adequate cuff and channel inflation.
In addition, graft 401 main body 402 and/or legs 404, 405 may, upon initial retraction of outer tubular member 431 and deployment into the vasculature, resist the “windsock” effect that tends to open up the graft to its nominal diameter. Then in turn may lead to inadequate cuff 413, 414, and 415 and channel 418 patency prior to their injection with inflation material. The windsock effect has a higher likelihood of being hindered when graft 401 is deployed in relatively tortuous or angled anatomies; however, it may also be made more difficult when graft 401 (and even tubular graft embodiments such as graft 11) is deployed in relatively non-tortuous anatomies.
To address this issue, we have found it useful to incorporate an optional ripcord or monofilament into the inflatable channel 418. Pre-loading such a ripcord 510 into all or a portion of the channel 418 that runs along graft ipsilateral leg 404 and main body portion 402 promotes effective inflation of the graft cuffs and channels as will be described below in detail.
Ripcord 510 extends in one embodiment from distal cuff 413 through channel 418, proximal cuff 414 and inflation port 421, and continues through inflation tube 444 and through second side arm 499 of proximal adapter 427 as shown in
In use, after graft 401 has been deployed into the vasculature but prior to injecting the inflation material through second side arm 499, the operator removes fitting 521 from catheter 523 and pulls ripcord 510 proximally out of the ipsilateral graft channel 418, second side arm 499 and out through the end of catheter 523. This leaves behind an unobstructed lumen in channel 418 through which inflation material may pass as it is injected into the device, despite any folds, wrinkles, or angles that may exist in graft 401 due to vessel tortuosity or angulation, lack of windsocking, or other phenomena. Inflation material may then be injected into channel 418 and cuffs 413, 414 and 415 through second side arm 499 as described elsewhere herein. Inflation material passes through the lumen in channel 418 left behind after ripcord 510 is removed and reaches distal cuff 413. As cuff 413 fills, a hemostatic seal is created at distal end of graft 401 which promotes the desired windsocking of the graft. This in turn promotes the effective filling of the rest of the cuffs 414, 415 and channels 418 and any other lumens in which the inflation material may be directed.
Suitable materials for ripcord 510 include polymeric monofilaments, such as PTFE, Polypropylene, nVion, etc. Metallic filaments such as stainless steel, nickel titanium, etc. may be used as well. The diameter of ripcord 510 should be small compared to the diameter of channel 418 lumen to minimize impact on delivery system profile, yet large enough to permit reasonable flow of inflation material into channel 418 lumen following its removal. We have found that a ripcord 510 diameter of between about 0.005 inch and 0.025 inch to be appropriate; in particular, a ripcord diameter of about 0.015 inch is suitable.
Alternatively, or in conjunction with ripcord 510, one or more permanent monofilament lumen patency members or beads may be incorporated into one or more of the cuffs and channels to facilitate the inflation process. We have found it useful to incorporate a single bead into graft contralateral leg 405 channel 418 along with ripcord 510 in the graft ipsilateral leg 404 channel 418.
Channel 418 is shown in
Bead 520 may have the same dimensions and comprise materials the same as or similar to ripcord 510. In particular, we have found a PTFE bead having a diameter of about 0.020 inch to be useful in the channel 418 embodiments of the present invention.
We have found that incorporating a ripcord 510 and/or one or more lumen patency members 520 in the system of the present invention enhances the likelihood that graft cuffs and channels will reliably and sufficiently fill with inflation material. In one extreme experiment designed to test the feasibility of this concept, a bifurcated graft contralateral leg 405 having a bead 520 disposed in the contralateral limb channel 418 was tied into a knot at the leg proximal end 417. Inflation material was injected through ipsilateral leg inflation port 421 under a pressure-control protocol. All cuffs and channels of graft 401, including contralateral leg channel 418 and proximal cuff 415, filled completely without having to increase the fill pressure beyond normal levels.
Although the benefits of ripcord 510 and one or more beads 520 (together or in combination) may be most readily gained when graft 401 is deployed in tortuous or highly angled anatomies, these components are also useful in grafts deployed in relatively straight and non-tortuous anatomies. They may also be used in tubular stent-grafts of the present invention.
Turning now to
Shown in
Within the well 633, the release strand 629 is arranged to form a “u-turn” in which it changes direction to double back on itself at juncture 641 as shown in
In use, the configuration of
A ball capture tip 638A or similar member may optionally be disposed on the tip 644 of second guidewire 638 to facilitate its capture by snare catheter 643 and prevent possible injury to the vessel intima. In addition, tip 638A may be made radiopaque so that it may be readily located by the operator during the procedure. When in the form of a ball, tip 638A may have a diameter ranging from between about 0.020 inch to about 0.120 inch, specifically, between about 0.040 inch to about 0.060 inch. Although not shown in the figures, second guidewire 638 may also have one or more additional sections branching therefrom, each having a tip or member similar to tip 644, including tip 638A, so to provide the operator with one or more alternative sites for capture with snare 643 in case tip 638A is inaccessible.
An angled extension 639A may optionally be provided on one or both of the top of optional lumen 639 and/or the top of well 633. Angled extension 639A may be made of any suitable polymeric or metallic material such as stainless steel. As seen in
As the second guidewire 638 is pulled out of the inner tubular member 628 from the left femoral artery access hole 537 in the direction shown by the arrow 544 in
Alternatively, any number of other arrangements in which the release strand 629 may be fed out of the outer tubular member 628 in an orderly manner is within the scope of the present invention. For instance, the well 651 shown in
Yet another variation of this embodiment, shown in
Other variations, such as a block and tackle arrangement (not shown), are envisioned in which the release strand 663 is looped through a grommet or similar feature. The grommet provides the necessary friction to prevent the entire release strand 663 from pulling out of the well 652 in one mass as soon as the operator applies a force on a distal end thereof. Any arrangement in which a frictional or similar force is utilized to allow for the orderly dispensation of the release strand 663 from the shaft or post 661 is within the scope of the embodiment contemplated.
As shown in
Release strand 710 is affixed to release strand attachment member 706 at secondary belt support member proximal end 714 and is preferably a stainless steel wire having a diameter of between about 0.004 inch and 0.010 inch, although other materials and diameters may be used. Secondary belt 716 is shown disposed on support member 454 along with optional silicone tubing 711.
Chiefly in tortuous or angled anatomies, but also in straighter vessels, it is useful to allow for a degree of slack in the contralateral limb 405 to be loaded into the elongate shaft 423. Such slack helps the contralateral leg 405 negotiate various bends in the iliac and/or femoral arteries. The total amount of slack ΔI ideally necessary for a graft limb such as limb 405 to negotiate an angle ΔΘ is represented by the equation:
ΔI=dΔΘ
where “ΔΘ” is the cumulative angle change (the sum of the absolute value of the angles through which the limb must negotiate) along its length, measured in radians, and where “d” is the diameter of the graft limb.
The hinge design of
After graft 401 has been deployed, the apparatus of
Both primary and secondary belt support members are ideally radiopaque to facilitate withdrawal from the vasculature. Secondary belt support member 454 and hinge attachment member 704 should be flexible enough to turn the corner around graft bifurcation 406 with little or no permanent deformation as the operator withdraws the primary belt support member 452 in the direction of arrows 712.
Withdrawal of member 452 causes secondary belt support member 454 to first retreat from contralateral limb 405 until the proximal end 714 of secondary belt support member 454 clears the graft walls in the vicinity of bifurcation 406, allowing the hinge to further act to align secondary belt support member in a generally parallel relationship with primary belt support member 452 as both are then withdrawn through the ipsilateral leg 404 and eventually out of the patient's body through right femoral access hole 531. Release strand 710 follows secondary belt support member 454 out of the body.
FIGS. 59A-B depict a variation of this hinge design that limits rotation of the secondary belt support member 454 to a single plane. Here, hinge body 732 is fixedly disposed on a distal portion 451 of primary belt support member 452 and comprises an offset flanged pin 734 or like element. Pin 734 is disposed in an aperture 736 that runs through the distal end 508 of secondary belt support member 454 and hinge body 732. In this configuration, secondary belt support member 454 is rotatably secured to pin 734 by optional flange 738 and is free to rotate about pin 734 in the direction indicated by arrows 740 to facilitate withdrawal of the delivery apparatus from the patient. The optional offset feature of pin 734 assists in the extraction of the belt support members from the graft and the Patient's body after graft deployment.
Optional expanding member shield 724 comprises PET or similar polymeric material. Shield 724 acts as a shroud to cover proximal self-expanding member 408, protecting ipsilateral leg 404 from being damaged by self-expanding member 408 during delivery system assembly and graft deployment. Further, shield 724 prevents direct contact between contralateral self-expanding member 408 and ipsilateral self-expanding member 407, keeping the various self expanding member components from snaring one another or otherwise getting entangled. The exact position of graft contralateral proximal self-expanding member 408 relative to graft ipsilateral leg 404 and self-expanding member 407 will depend on several factors, one of which is the degree of slack built into the graft legs 404, 405 on members 452 and 454.
Shield 724 may be removed prior to retraction of secondary release wire 719 by retracting shield line 720 in the direction indicated by arrow 729, typically after release strand tube 718 has been removed, and ultimately out of the patient's body through left femoral artery access hole 537. As shield 724 is retracted, release strand 710 and secondary release wire 719 pass through wire apertures 728 and 730, respectively. Alternatively, a single wire aperture may be disposed on shield 724 through which both release strand 710 and secondary release wire 719 pass.
A variation in the deployment sequence that may be used with any of the sequences and equipment described above may be appropriate in certain clinical settings when the patient's vasculature exhibits a degree of tortuosity and/or angulation.
Related to the cuff and channel lumen patency matter discussed above are at least two additional considerations when deploying a device such as bifurcated graft 401 in tortuous or angled anatomies. First, it can be more challenging to maintain the patency of either or both the blood flow passageways formed by the walls of graft contralateral leg 405 and/or ipsilateral leg 404. Such challenges may also be presented in the blood flow passageways defined by graft main body 402 of the bifurcated graft 401 and tubular graft 11 embodiments. This may in turn negatively affect the patency of the cuff and channel lumens such that the cuffs and channels cannot adequately be filled with inflation material. Second, the outer tubular member 431 can be more difficult to retract proximally relative to inner tubular member 430 when the delivery system 400 is disposed in such angled and/or tortuous anatomies.
The delivery method discussed with respect to
During the delivery procedure, after the first and second distal self expanding members 411 and 412 have been released, the operator removes release strand tube 718 from the body through the left femoral access hole 537. This exposes release strand 710, secondary release wire 719, and shield line 720.
Next, the shield line 720 is pulled in a proximal direction 729 by the operator to remove shield 724 from the contralateral leg proximal end 417, exposing self-expanding member 408. A buttress, which can be a tubular member such as a catheter or the like, is threaded on the remaining secondary release wire 719 and release strand 710 and advanced distally until it physically abuts the proximal end 483 of the secondary belt support member 454. This provides a relatively stiff column that the operator may use to move the graft contralateral leq 405 in a distal direction as well as react the force necessary to deploy self-expanding member 408 by retracting release wire 719.
The operator next detaches Luer-type fitting or cap 521 from flexible fill catheter 523 and removes ripcord 510 from channel 418. Graft 401 cuffs and channels may then be filled with inflation material as previously described. When the inflation material is radiopaque or otherwise observable in vivo, the operator may interrogate the shape of the graft 401 and the various cuffs and channels under fluoroscopy or other suitable imaging technique to determine qraft limb patency, the sufficiency of graft cuff and channel inflation, and whether any folds or other irregularities in the graft exist so that they may be corrected. When observed under fluoroscopy, the operator may adjust the C-arm of the fluoroscope to interrogate graft 401 from a number of angles.
If necessary, and after cuff and channel inflation but before proximal self-expanding member deployment, the operator may manipulate both the buttress catheter and/or release strand 710 to push or pull, respectively, the qraft contralateral leq into. the proper position. By making fine adjustments in either direction, the operator may remove or add slack in the graft contralateral leg 405 and ensure optimal qraft placement and patency. To minimize operator confusion, the release strand 710 and stent release wire 719 may be different lenqths, color coded, flagged or otherwise labeled, etc. We have found that making the stent release wire 719 shorter than release strand 710 helps in maintaining optimal operator orientation with respect to the various components of the qraft delivery system.
When the operator is satisfied with the position, patency, and appearance of graft 401, contralateral self-expanding member 408 may be deployed by applying tension in the proximal direction 729 on secondary release wire 719 so that secondary belt 716 releases proximal self-expanding member 408 in the manner previously described.
Similarly, the operator next may adjust the position of the ipsilateral leg 404 of graft 401 by adjusting the position of primary belt support member 452 and then release proximal self-expanding member 407 of the ipsilateral leg 404 as described herein.
To withdraw the delivery apparatus, guide wire 530 is partially withdrawn in the proximal direction through nosepiece 434 into guide wire tube 436 to a point proximal of cuff 413. This prevents the guide wire 530 from possible interference with proper inflation of cuff 413. Next, the distal end 487 of the inflation tube 444 may be disengaged from the inflation port 421 by pulling on a proximal end 491 of retention wire 488 as previously discussed. Using the buttress to push on belt support member proximal portion 483 if necessary, the operator may then proximally withdraw the primary belt support member 452 over guide wire 530 with the secondary belt support member 454 following. Finally, guide wire 530 is removed through left and right femoral access holes 537, 531, which may then be repaired using conventional techniques.
It is clear to those of skill in the art that although particular techniques and steps are described herein that we have found to be useful, variations in the order and techniques in which the various deployment steps described herein are within the scope of the present invention.
While particular forms of the invention have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be so limited.
Claims
1. A delivery system for a bifurcated intracorporeal device comprising:
- an elongate shaft having a proximal section and a distal section with the distal section comprising: an elongate primary belt support member; at least one primary belt secured to the primary belt support member configured to be circumferentially disposed about a bifurcated intracorporeal device so to at least partially constrain the device; a primary release member configured to engage and releasably secure the primary belt in a constraining configuration; at least one elongate secondary belt support member disposed adjacent the elongate primary belt support member; at least one secondary belt secured to the secondary belt support member configured to be circumferentially disposed about a bifurcated intracorporeal device so to at least partially constrain the device; and a secondary release member configured to engage and releasably secure the secondary belt in a constraining configuration.
2. The delivery system of claim 1 wherein the primary belt support member is an elongate tubular member and the bifurcated intracorporeal device is a bifurcated endovascular graft in a constrained state.
3. The delivery system of claim 1 wherein the primary belt and secondary belt each comprise a length of wire having a first end and a second end with each of said first and second wire ends secured to the primary belt support member, and secondary belt support member respectively.
4. The delivery system of claim 1 wherein one or both of the primary belt and the secondary belt comprise first and second opposed ends and wherein the first opposed end has a different cross-sectional area than the second opposed end.
5. The delivery system of claim 4 wherein each of the first and second opposed ends form an end loop.
6. The delivery system of claim 3 wherein the wire comprises nickel titanium.
7. The delivery system of claim 1 wherein the release members comprise release wires moveably disposed within opposed looped ends of the respective belts.
8. The delivery system of claim 1 wherein the belts in the constraining configuration form a plane that is substantially orthogonal to a longitudinal axis of the elongate shaft.
9. The delivery system of claim 1 wherein at least two belts are configured to be releasable by a single release member.
10. The delivery system of claim 1 comprising a plurality of primary release members wherein the proximal ends of at least two of the primary release members are color-coded.
11. The delivery system of claim 1 comprising a plurality of primary release members wherein proximal ends of the primary release members are in a linear spatial configuration at a proximal end of the delivery system that corresponds to a desired deployment sequence for a plurality of belts.
12. The delivery system of claim 11 wherein the plurality of primary release members comprise a distal primary release wire handle and a proximal primary release wire handle disposed in a nested configuration.
13. The delivery system of claim 1 wherein the primary release member comprises a branched release wire.
14. The delivery system of claim 1 further comprising a secondary belt support member housing secured to the primary belt support member wherein the secondary belt support member is configured to move axially within the housing and the housing and secondary belt support member are configured to prevent relative rotational movement therebetween.
15. A delivery system for a bifurcated graft comprising:
- an elongate shaft having a proximal section and a distal section with the distal section comprising: a portion having disposed thereon the bifurcated graft, the graft having a main body portion, an ipsilateral leg and a contralateral leg; an elongate primary belt support member disposed adjacent the main body portion and ipsilateral leg; at least one primary belt secured to the primary belt support member and circumferentially disposed about the bifurcated graft and which constrains at least a portion of the graft; a primary release member which releasably secures the primary belt in the constraining configuration; at least one secondary belt support member disposed adjacent the contralateral leg; at least one secondary belt secured to the secondary belt support member and circumferentially disposed about the bifuircated graft and which constrains at least a portion of the graft; and a secondary release member which releasably secures the secondary belt in the constraining configuration.
16. The delivery system of claim 15 additionally comprising a first proximal self-expending member secured to a proximal end of the contralateral leg and a second proximal self-expanding member secured to a proximal end of the ipsilateral leg, and wherein the legs have a different length and the first and second proximal self-expanding members are axially offset from each other when the graft is in a constrained state within the delivery system.
17. The delivery system of claim 15 additionally comprising a first proximal self-expanding member secured to a proximal end of the contralateral leg and a second proximal self-expanding member secured to a proximal end of the ipsilateral leg and wherein the legs have substantially the same length and one of the legs is axially compressed or folded such that the first and second proximal self-expanding members are axially offset from each other when the graft is in a restrained state within the delivery system.
18. The delivery system of claim 15 wherein the primary belt constrains a distal self-expanding member disposed at a distal end of the bifurcated graft main body portion.
19. The delivery system of claim 16 wherein the distal self-expanding member is a tubular stent.
20. The delivery system of claim 17 wherein the stent comprises a circumferential groove configured to accept at least a portion of the primary belt.
21. The delivery system of claim 15 wherein the primary belt and the secondary belt comprise at least one length of wire having a first end and a second end and configured in a loop with each of said first and second wire ends secured to the primary belt support member and secondary belt support member, respectively.
22. The delivery system of claim 15 wherein the primary belt and secondary belt comprise at least one length of wire having opposed end loops having differing diameters.
23. The delivery system of claim 21 wherein the wire comprises nickel titanium.
24. The delivery system of claim 15 wherein the release members comprise release wires moveably disposed within opposed looped ends of the respective belts.
25. The delivery system of claim 15 wherein the belts in the constraining configuration form a plane that is substantially orthogonal to a longitudinal axis of the elongate shaft.
26. The delivery system of claim 15 wherein at least two primary belts are configured to be releasable by the same release member.
27. The delivery system of claim 15 wherein the primary belt support member comprises a guidewire tube.
28. The delivery system of claim 26 wherein the distal section further comprises an outer protective sheath disposed about the endovascular graft while the graft is in a constrained state.
29. A delivery system for a bifurcated graft having a main body portion, an ipsilateral leg, contralateral leg and a plurality of self-expanding members secured to the graft, comprising:
- an elongate shaft having a proximal section and a distal section with the distal section of the elongate shaft comprising: a portion having disposed thereon the bifurcated graft; an elongate primary belt support member disposed within the main body portion and ipsilateral leg of the bifurcated graft; a plurality of primary belts secured to a primary belt support member comprising a guidewire tube adjacent self-expanding members of the graft, the belts being circumferentially disposed about adjacent self-expanding members in a configuration that at least partially constrains the respective self-expanding members; a primary release wire that engages and releasably secures at least one of the primary belts in a constraining configuration; a secondary belt support member disposed within the contralateral leg of the bifurcated graft; a secondary belt secured to the belt support member adjacent self-expanding members of the graft, the belt being circumferentially disposed about an adjacent self-expanding member in a configuration that at least partially constrains the adjacent self-expanding member; and a secondary release wire that engages and releasably secures the secondary belt in a constraining configuration.
30. A delivery system for a bifurcated intracorporeal device comprising:
- an elongate shaft means having a proximal section and a distal section with the distal section comprising: an elongate primary constraint support means; at least one primary constraint means secured to the primary constraint support means configured to be circumferentially disposed about a bifurcated intracorporeal device so to at least partially constrain the device; a primary release means configured to engage and releasably secure the primary constraint means in a constraining configuration; at least one elongate secondary constraint support member disposed adjacent the elongate primary constraint support means; at least one secondary constraint means secured to the secondary constraint support means configured to be circumferentially disposed about a bifurcated intracorporeal device so to at least partially constrain the device; and a secondary release means configured to engage and releasably secure the secondary constraint means in a constraining configuration.
31. The delivery system of claim 30 wherein the primary constraint support means is an elongate tubular means and the bifurcated intracorporeal device is a bifurcated endovascular graft in a constrained state.
32. The delivery system of claim 30 wherein one or both of the primary constraint means and the secondary constraint means comprise first and second opposed ends and wherein the first opposed end has a different cross-sectional area than the second opposed end.
33. The delivery system of claim 30 wherein the constraint means in the constraining configuration form a plane that is substantially orthogonal to a longitudinal axis of the elongate shaft means.
34. The delivery system of claim 30 wherein at least two of the constraint means are configured to be releasable by a single release means.
35. The delivery system of claim 30 comprising a plurality of primary release means wherein the proximal ends of at least two of the primary release means are color-coded.
36. The delivery system of claim 30 comprising a plurality of primary release means wherein proximal ends of the primary release means are in a linear spatial configuration that corresponds to a desired deployment sequence for a plurality of constraint means.
37. A delivery system for a bifurcated graft comprising:
- an elongate shaft means having a proximal section and a distal section with the distal section comprising: a portion having disposed thereon the bifurcated graft, the graft having a main body portion, an ipsilateral leg and a contralateral leg; an elongate primary constraint support means disposed adjacent the main body portion and ipsilateral leg; at least one primary constraint means secured to the primary constraint support means and circumferentially disposed about the bifurcated graft and which constrains at least a portion of the graft; a primary release means which releasably secures the primary constraint means in the constraining configuration; at least one secondary constraint support means disposed adjacent the contralateral leg; at least one secondary constraint means secured to the secondary constraint support means and circumferentially disposed about the bifurcated graft and which constrains at least a portion of the graft; and a secondary release means which releasably secures the secondary constraint means in the constraining configuration.
38. The delivery system of claim 37 wherein the primary constraint means constrains a distal self-expanding member disposed at a distal end of the bifurcated graft main body portion.
39. The delivery system of claim 37 wherein the constraint means in the constraining configuration form a plane that is substantially orthogonal to a longitudinal axis of the elongate shaft means.
40. A delivery system for a bifurcated graft having a main body portion, an ipsilateral leg, contralateral leg and a plurality of self-expanding members secured to the graft, comprising:
- an elongate shaft means having a proximal section and a distal section with the distal section of the elongate shaft comprising: a portion having disposed thereon the bifurcated graft; an elongate primary constraint support means comprising a guidewire tube means disposed within the main body portion and ipsilateral leg of the bifurcated graft; a plurality of primary constraint means secured to the primary constraint support means adjacent respective self-expanding members of the graft, the primary constraint means being circumferentially disposed about the adjacent self-expanding members in a configuration that at least partially constrains the respective self-expanding members; a primary release means that engages and releasably secures at least one of the primary constraint means in a constraining configuration; a secondary constraint support means disposed within the contralateral leg of the bifurcated graft; a secondary constraint means secured to the secondary constraint support means adjacent respective self-expanding members of the graft, the secondary constraint means being circumferentially disposed about the adjacent self-expanding members in a configuration that at least partially constrains the adjacent self-expanding members; and a secondary release means that engages and releasably secures the secondary constraint means in a constraining configuration.
41. A delivery system for an expandable intracorporeal device comprising:
- an elongate shaft having a proximal section and a distal section with the distal section of the elongate shaft comprising: a portion having disposed thereon the expandable intracorporeal device; an elongate belt support member disposed adjacent a portion of the expandable intracorporeal device; a belt secured to the belt support member and circumferentially disposed about the expandable intracorporeal device and which constrains at least a portion of the expandable intracorporeal device; and a release member which releasably secures the belt in the constraining configuration.
42. The delivery system of claim 41 wherein the belt constrains a self-expanding portion of the expandable intracorporeal device.
43. The delivery system of claim 42 wherein the self-expanding portion is a tubular stent.
44. The delivery system of claim 43 wherein the stent comprises a cicumferential groove configured to accept at least a portion of the belt.
45. The delivery system of claim 41 wherein the belt support member is an elongate tubular member and the expandable intracorporeal member is an endovascular graft in a constrained state.
46. The delivery system of claim 41 wherein the belt comprises at least one length of wire having a first end and a second end.
47. The delivery system of claim 46 wherein the at least one length of wire is configured in at least one loop with each of said first and second wire ends secured to the belt support member.
48. The delivery system of claim 46 wherein the wire comprises a shape memory alloy.
49. The delivery system of claim 48 wherein the wire comprises nickel titanium.
50. The delivery system of claim 41 wherein the release member comprises a release wire releasably secured to at least one end of the belt.
51. The delivery system of claim 50 wherein the release wire is moveably disposed within opposed looped ends of the belt.
52. The delivery system of claim 41 wherein the belt in the constraining configuration forms a plane which is substantially orthogonal to a longitudinal axis of the elongate shaft.
53. The delivery system of claim 41 wherein a plurality of belts are secured to various axial positions on the belt support member and circumferentially disposed about the expandable intracorporeal device and have a configuration that constrains the expandable intracorporeal device, and
- at least one release member that releasably secures the belts in the constraining configuration.
54. The delivery system of claim 53 wherein the number of belts is three.
55. The delivery system of claim 53 wherein at least two belts are configured to be releasable by the same release member.
56. The delivery system of claim 53 wherein all the belts are configured to be releasable by the same release member.
57. The delivery system of claim 55 wherein the order in which the at least two belts are released is determined by the axial position of the at least two belts and the direction of movement of the at least one release member.
58. The delivery system of claim 57 wherein the at least one release member comprises a release wire moveably disposed within opposed looped ends of each belt and wherein the delivery system is configured such that a distal-most belt will be released first when a distal end of the release wire is retracted in a proximal direction so as to move past the looped ends of the distal-most belt, and belts located more proximally are released sequentially thereafter as the distal end of the release wire passes the respective looped ends thereof.
59. A delivery system for an endovascular graft with a flexible tubular body portion and at least one self-expanding member secured to the flexible tubular body portion, comprising:
- an elongate shaft having a proximal section and a distal section with the distal section of the elongate shaft comprising:
- a portion having disposed thereon the self-expanding endovascular graft;
- an elongate belt support member disposed adjacent the self-expanding member of the endovascular graft;
- a belt secured to the belt support member adjacent the self-expanding member and circumferentially disposed about the self-expanding member and which has a configuration which constrains the self-expanding member; and
- a release wire releasably securing ends of the belt in the constraining configuration.
60. The delivery system of claim 59 wherein the belt support member comprises a guidewire tube.
61. The delivery system of claim 59 wherein the belt comprises nickel titanium.
62. The delivery system of claim 59 wherein the endovascular graft comprises a plurality of self-expanding members and wherein a plurality of belts are secured to various axial positions on the belt support member adjacent the plurality of self-expanding members, and circumferentially disposed about the self-expanding members and having a configuration which constrains the self-expanding members.
63. The delivery system of claim 62 wherein the release wire is moveably disposed within opposed looped ends of the belts and configured such that a distal-most belt will be released first when a distal end of the release wire is retracted in a proximal direction so as to move past the looped ends of the distal most belt, and belts located more proximally in an axial direction are released sequentially thereafter as the distal end of the release wire passes the respective looped ends thereof.
64. The delivery system of claim 62 wherein the distal section of the delivery system comprises at least two release wires configured to release different belts.
65. The delivery system of claim 59 wherein the distal section further comprises an outer protective sheath disposed about the endovascular graft while the graft is in a constrained state, the belts being in their constraining configuration and at least a portion of the release wire being disposed at the belts.
66. A delivery system for an endovascular graft with a flexible tubular body portion and a plurality of self-expanding members secured to the tubular body portion, comprising:
- an elongate shaft having a proximal section and a distal section with the distal section of the elongate shaft comprising:
- a portion having disposed thereon a self-expanding endovascular graft;
- an elongate guidewire tube disposed within the endovascular graft with the endovascular graft being in a constrained state;
- a plurality of shape memory wire belts secured to the guidewire tube adjacent the respective self-expanding members, the belts being circumferentially disposed about the respective self-expanding members and which have a configuration that constrains the respective self-expanding members;
- a first release wire that releasably secures ends of the belts disposed about the self-expanding members at the distal end of the endovascular graft in the constraining configuration; and
- a second release wire that releasably secures ends of the belts disposed about the self-expanding members at the proximal end of the endovascular graft in the constraining configuration.
67. A delivery system for an expandable intracorporeal device comprising:
- an elongate shaft having a proximal section and a distal section with the distal section comprising:
- an elongate belt support member disposed adjacent a portion of the distal portion configured to receive an expandable intracorporeal device;
- at least one belt secured to the belt support member and which is configured to be circumferentially disposed about the expandable intracorporeal device to constrain the expandable intracorporeal device; and
- a release member which releasably secures the belt in the constraining configuration.
68. The delivery system of claim 67 wherein the belt support member is an elongate tubular member and the expandable intracorporeal member is an endovascular graft in a constrained state.
69. The delivery system of claim 67 wherein the belt comprises at least one length of wire having a first end and a second end.
70. The delivery system of claim 69 wherein the at least one length of wire is configured in at least one loop with each of said first and second wire ends secured to the belt support member.
71. The delivery system of claim 69 wherein the wire comprises a shape memory alloy.
72. The delivery system of claim 71 wherein the wire comprises nickel titanium.
73. The delivery system of claim 67 wherein the release member comprises a release wire releasably secured to loop ends of the belt.
74. The delivery system of claim 73 wherein the release wire is moveably disposed within opposed looped ends of the belt.
75. The delivery system of claim 67 wherein the belt in the constraining configuration forms a plane which is substantially orthogonal to a longitudinal axis of the elongate shaft.
76. The delivery system of claim 67 wherein the delivery system comprises a plurality of belts.
77. The delivery system of claim 76 wherein at least two belts are configured to be releasable by the same release member.
78. The delivery system of claim 76 wherein all the belts are configured to be releasable by the same release member.
79. The delivery system of claim 77 wherein the order in which the at least two belts are released is determined by the axial position of the at least two belts and the direction of movement of the at least one release member.
80. The delivery system of claim 79 wherein the at least one release member comprises a release wire moveably disposed within at least one end of each belt and wherein the delivery system is configured such that a distal-most belt will be released first when a distal end of the release wire is retracted in a proximal direction so as to move past the at least one end of the distal-most belt, and belts located more proximally are released sequentially thereafter as the distal end of the release wire passes the respective ends thereof.
81. The delivery system of claim 76 further comprising a plurality of release members wherein at least a portion of the proximal end of at least two of the release members are different colors.
82. The delivery system of claim 81 wherein the release members comprise release wire handles secured to proximal ends of release wires and at least a portion of at least two of the release wire handles are of different colors.
83. The delivery system of claim 76 further comprising a plurality of release members wherein proximal ends of the release members are in a linear spatial configuration at a proximal end of the delivery system that corresponds to a desired deployment order for the plurality of belts.
84. The delivery system of claim 76 wherein the release member comprises a branched release wire.
Type: Application
Filed: Aug 15, 2005
Publication Date: Jan 12, 2006
Applicant: TriVascular, Inc. (Santa Rosa, CA)
Inventors: Michael Chobotov (Santa Rosa, CA), Brian Glynn (Santa Rosa, CA)
Application Number: 11/205,793
International Classification: A61F 2/06 (20060101);