WO2010027704A1

WO2010027704A1 - Extravascular supports and methods

Info

Publication number: WO2010027704A1
Application number: PCT/US2009/054618
Authority: WO
Inventors: Judah Z. Weinberger
Original assignee: Weinberger Judah Z
Priority date: 2008-09-08
Filing date: 2009-08-21
Publication date: 2010-03-11

Abstract

Devices and method can treat an aneurysm or other condition by providing extravascular support to at least partially wrap a target location of a blood vessel. Devices and methods allow guiding members to be used to guide or place a support sheet about a target location. The guiding members can then be released from the sheet.

Description

EXTRAVASCULAR SUPPORTS AND METHODS

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This patent application claims priority under 35 U. S. C. 119(e) to U.S. Patent

Application Serial No.: 61/095,166, filed September 8, 2008, entitled EXTRAVASCULAR SUPPORTS AND METHOD, which patent application is related to Judah Weinberger, U.S. Patent Application Serial No. 10/992,297 entitled METHODS AND DEVICES FOR EXTRAVASCULAR INTERVENTION, which was filed on November 18, 2004, and which published on May 18, 2006 as U.S. Patent Publication No. 2006/0106406A1, which is a continuation-in-part application of U.S. Patent Application Serial No. 10/952,281, entitled METHODS AND DEVICES FOR EXTRAVASCULAR INTERVENTION, which was filed on September 27, 2004, the disclosure of each which is incoiporated by reference herein in its entirety.

BACKGROUND

This document generally relates to methods and devices for vascular intervention, such as for treating one or more vascular diseases or conditions, including, but not limited to, aneurysms. An aneurysm is generally conceptualized as a dilation, widening, or bulge of a weakened wall of a blood vessel. Although aortic aneurysms are the most common types of aneurysm, aneurysms can occur in any artery. Aneurysms are typically associated with, or secondary to, arteriosclerosis, trauma to the aorta, inflammation of the wall of the aorta, or one or more hereditary conditions such as Marfan' s syndrome. A patient afflicted with an aneurysm may experience pain and discomfort, particularly as the aneurysm grows. Additionally, aneurysms can rupture. This can pose a relatively high mortality risk that is i estimated at about 50% for abdominal aortic aneurysms and greater for thoracic aneurysms. The risk associated with rupture is generally based on the size of the aneurysm in relation to the normal or average size for the particular vessel afflicted with the aneurysm. For example, the risk of rupture within two years of discovery ^{~ ~}israbour50%^~for an aortic aneurysm measuring atrleasT5-6^~cm7^~

Presently, aortic aneurysm treatments or interventions are believed generally limited either to replacement of the affected section of the aorta with a prosthetic graft, or implantation of an endovascular graft or endograft within the aorta. However, replacement with a prosthetic graft requires invasive and complex open- surgical intervention, with an estimated full recovery of about 6 weeks thereafter. Furthermore, open-surgical intervention is associated with a relatively high risk of mortality: about 5% for abdominal aortic aneurysms and about 15% for thoracic abdominal aneurysms. The high risk of mortality associated with open-surgical intervention has generally limited the procedure to the treatment of aortic aneurysms of about 5-6 cm or greater.

Endovascular graft implants are typically fabric-covered metallic stents that are passed (in a collapsed form) through a femoral artery, into the dilated section of the aorta. At the aorta, the stent graft can be expanded to secure the endovascular graft to normal or unaffected sections of the aorta, above and below the aneurysmal section of the aorta. Although less invasive than a surgical prosthetic graft, endovascular graft implants are believed limited to use in patients having anatomy suited for endovascular grafts. As an illustrative example, since the endovascular graft typically passes through the femoral artery, patients having narrow or occluded femoral or iliac arteries may not be suited for treatment with an endovascular graft. Additionally, endovascular grafts, and the devices necessary for their implantation, are relatively complex, resulting in a costly procedure. They also have a tendency to migrate after implantation or to develop leaks.

Navigational requirements for the endovascular graft implant can further inhibit or prevent its use in the treatment of aneurysms in vessels with acute bends, such as the arch of the aorta, and in vessels through which one must navigate to reach the target vessel, such as the ascending aorta. The risk of mortality associated with the endovascular graft is estimated to be about the same as that of the open- surgical intervention procedure. Thus, the use of endovascular graft implants is also limited to the treatment of aneurysms of about 5-6 cm or greater.

OVERVIEW

The present inventor has recognized, among other things, a need for methods and devices for aneurysm intervention, for example, that can entail a lesser degree of complexity in their performance, and a lower cost associated therewith. The present inventor has also recognized a need for methods and devices for aneurysm intervention that exhibit a lower rate of mortality and, as such, are suitable for the treatment of patients independent of the size of the aneurysm, and, particularly, are suitable for the treatment of aneurysms of less than 5 cm. The present inventor has further recognized a need for methods and devices for inhibiting or preventing endovascular graft implant migration. Further, the present inventor has also recognized that there is also a need for methods and devices generally suitable for the treatment of a patient with an aneurysm, independent of the patient's endovascular anatomy.

This document describes, among other things, devices and method that can treat an aneurysm or other condition by providing extravascular support to at least partially wrap a target location of a blood vessel. This document also describes, among other things, devices and methods that allow guiding members to be used to guide or place a support sheet about a target location. The guiding members can then be released from the sheet.

Example 1 describes a device. In this example, the device can include an extravascular support sheet, sized and shaped to permit placement at least partially around a blood vessel of a human or animal subject. In this example, the support sheet can comprise a thickness, a width, and a length, wherein the length is configured to extend longitudinally along the blood vessel, wherein the width is configured to extend at least partially around the blood vessel, and wherein the sheet is capable of providing a longitudinal opening to accept the blood vessel within an at least partially enclosed interior region provided by the sheet. In this example, the sheet can include first and second couplings separated from each other along the sheet by at least a substantial portion of the width, the first coupling configured to be coupled to a leading member during the placement of the sheet at least partially around the blood vessel, the second coupling configured to be coupled to a trailing memfrer during theηplaσementT)^{^}^^{^}^

In Example 2, the device of Example 1 can optionally comprise third and fourth couplings separated from each other by at least a substantial portion of the width, the third coupling configured to be coupled to a leading member during the placement of the sheet at least partially around the blood vessel, the fourth coupling configured to be coupled to a trailing member during the placement of the sheet at least partially around the blood vessel. In this example, the first and third couplings are separated from each other by a substantial portion of the length, and the second and fourth couplings are separated from each other by a substantial portion of the length. In Example 3, the device of any one or more of Examples 1-2 optionally can be configured such that at least one of the first, second, third, and fourth couplings comprises a hole extending through the sheet.

In Example 4, the device of any one or more of Examples 1-3 optionally can be configured such that the hole is sized and shaped to receive at least one of the leading member or the trailing member through the hole.

In Example 5, the device of any one or more of Examples 1-4 optionally can include at least one of the leading member or the trailing member.

In Example 6, the device of any one or more of Examples 1 -5 optionally can be configured such that at least one of the leading member or the trailing member comprises a specified breakaway location about which the member is configured to break apart when forces on opposing sides of the breakaway location exceed a specified value.

In Example 7, the device of any one or more of Examples 1-6 optionally can be configured such that the sheet and the at least one of the leading member or the trailing member are provided together in a kit. In Example 8, the device of any one or more of Examples 1-7 optionally can be configured such that at least one of the leading member or the trailing member includes at least one of a loop, a knot, a widened portion, or a snap-fitting.

In Example 9, the device of any one or more of Examples 1-8 optionally can ^"5- — be configured such thatthe sheet is deformable and comprises a shape-memory property such that, when released from being deformed, the sheet tends to resume its previous shape before being deformed, and wherein the first and second couplings are located on the sheet so as to tend to flatten the sheet when the leading member and the trailing member exert opposing forces on the first and second0 couplings.

In Example 10, the device of any one or more of Examples 1-9 optionally can be configured such that the sheet comprises a deformable scaffold that comprises the shape-memory property.

In Example 11, the device of any one or more of Examples 1-10 optionally 5 further comprises first and second fasteners, separated from each other by at least a substantial portion of the width, the first and second fasteners configured to be coupled to each other to secure the sheet in place at least partially around a blood vessel.

In Example 12, the device of any one or more of Examples 1-11 can 0 optionally be configured such that at least one of the first or second couplings comprises a resilient hook configured to receive and retain a guiding member, and to release the guiding member when a force exceeding a threshold value is applied to the guiding member.

Example 13 comprises a method. In this example, the method comprises5 providing or using an extravascular support sheet, sized and shaped to permit placement at least partially around a blood vessel of a human or animal subject, the support sheet comprising a thickness, a width, and a length, wherein the length is configured to extend longitudinally along the blood vessel, wherein the width is configured to extend at least partially around the blood vessel, and wherein the sheet0 is capable of providing a longitudinal opening to accept the blood vessel within an at least partially enclosed interior region provided by the sheet. In this example, the method also comprises providing or using a first leading member and a first trailing member capable of being associated with the sheet at locations that are separated from each other by at least a substantial portion of the width.

In Example 14, the method of Example 13 can optionally include attaching the firstieading member tcrarfirsircoupliflg assOxfate^wttrrtrfe^"srieet7attaching1;hF first trailing member to a second coupling associated with the sheet, and wherein the first and second couplings are separated from each other by at least a substantial portion of the width.

In Example 15, the method of any one or more of Examples 13-14 can optionally comprise placing the sheet into position at least partially around the blood vessel, including applying opposing forces to the first leading and first trailing members to open the sheet while placing the sheet, then releasing the opposing forces to allow the sheet to self-close at least partially around the blood vessel. In Example 16, the method of any one or more of Examples 13-15 can optionally comprise attaching a second leading member to a third coupling associated with the sheet; attaching a second trailing member to a fourth coupling associated with the sheet; wherein the third and fourth couplings are separated from each other by at least a substantial portion of the width; wherein the first and third couplings are separated from each other by at least a substantial portion of the length; and wherein the second and fourth couplings are separated from each other by at least a substantial portion of the length.

In Example 17, the method of any one or more of Examples 13-16 can optionally be performed such that placing the sheet into position at least partially around the blood vessel includes applying opposing forces to the second leading and second trailing members to open the sheet while placing the sheet, then releasing the opposing forces to allow the sheet to self-close at least partially around the blood vessel.

In Example 18, the method of any one or more of Examples 13-17 can optionally comprise providing at least one of: (1) the first leading member and the first trailing member as a single flexible member extending through holes provided by the first and second couplings; or (2) the second leading member and the second trailing member as a single flexible member extending through holes provided by the third and fourth couplings.

In Example 19, the method of any one or more of Examples 13-18 can optionally comprise tying the first leading member or the first trailing member to a locΕ:tiOn^{^}aΕsociate^withlheTheet7

In Example 20, the method of any one or more of Examples 13-19 can optionally comprise breaking apart at least one of the first leading member or the first trailing member after the sheet has been placed into location at least partially around the blood vessel. In Example 21 , the method of any one or more of Examples 13-20 can optionally comprise separating the vessel about which the sheet it to be at least partially positioned from a nearby vessel by introducing the leading member therebetween.

In Example 22, the method of any one or more of Examples 13-21 can optionally comprise introducing the sheet, the first leading member, and the first trailing member into the subject using a minimally invasive surgical technique that includes using first and second extravascular portals into the subject located on opposing sides of the vessel about which the sheet is to be at least partially positioned. In Example 23, the method of any one or more of Examples 13-22 can optionally comprise providing instructions for using the extravascular support sheet. In Example 24, the method of any one or more of Examples 13-23 can optionally comprise snap-fitting the first leading member or the first trailing member to a location associated with the sheet. In Example 25, the method of any one or more of Examples 13-24 can optionally comprise releasing the first leading member or the first trailing member from the sheet by applying a force exceeding a threshold value to deform a resilient portion of the sheet.

In Example 26, the method of any one or more of Examples 13-25 can optionally be performed such that the providing or using a first leading member and a first trailing member capable of being associated with the sheet at locations that are separated from each other by at least a substantial portion of the width comprises using a unitary member as both the first leading member and the first trailing member.

In Example 27, the method of any one or more of Examples 13-26 can O^~ptiO^~nally^~cOmpTϊse^~foπmng^ first trailing member, and using the knot to pull against the support sheet to help position the support sheet.

In Example 28, the method of any one or more of Examples 13-27 can optionally comprise untying the knot and then releasing the support sheet from at least one of the first leading member or the first trailing member.

This overview is intended to provide an overview of subject matter of the present patent application. It is not intended to provide an exclusive or exhaustive explanation of the invention. The detailed description is included to provide further information about the present patent application.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

FIG. 1 is an example of an anterior plan view of a human aorta, showing examples of typical locations where aortic aneurysms may occur.

FIG. 2 is an example of a cross-sectional view of an example of a blood vessel having an aneurysm.

FIGS. 3A-3B are examples of plan views of examples of extravascular intervention devices disposed around a vessel having an aneurysm.

FIGS. 4A-4F are examples of perspective views of several examples of extravascular intervention devices. FIGS. 5A-5B are examples of plan views of several examples of extravascular intervention devices disposed around a human aorta at typical locations whereon aortic aneurysms may occur.

FIGS. 6A-6D are examples of views of an example of an extravascular intervention device. FIG:-74s an example of a plan view of extravascular intervention devices- further implanted around an aneurysm with mesh or fabric between the struts.

FIG. 8 shows an example of an extravascular support sheet, which is normally curled such as shown in FIG. 4A, however, in the example of FIG. 8, the support sheet has been pulled flat.

FIG. 9 shows an illustrative example of a distal end-view of an elongated guiding member, which includes a male snap-fitting, such as can include a shaft and a protuberance.

FIG. 10 shows another example in which the guiding members can include a single suture thread that is looped through the corresponding hole coupling, drawn back, and optionally knotted, such as to form a loop.

FIG. 11 shows an example in which a pair of guiding members can be laced through the sheet.

FIG. 12 shows an example of an extravascular aneurysm support sheet, similar to that shown in FIG. 6A, but including resilient hook couplings at its four corners.

DETAILED DESCRIPTION

This document describes, among other things, devices and method that can treat an aneurysm or other condition by providing extravascular support to at least partially wrap a target location of a blood vessel. This document also describes, among otherthings; devices and inethodsihat allovr guiding members to^~be^~used to guide or place a support sheet about a target location. The guiding members can then be released from the sheet.

Aneurysms can occur in any blood vessel. However, aneurysms commonly and typically occur in the aorta. FIG. 1 shows an anterior view of a human aorta, depicting examples of typical locations on the aorta where aneurysms can occur. In the example of FIG. 1 , aortic aneurysms can occur in the thoracic cavity 102 or in the abdominal cavity 104. Aneurysms in the thoracic cavity can occur in any location, such as on the ascending aorta 106, the arch of the aorta 108, the descending aorta 109, the thoracic aorta 110, or any vessels branching therefrom. Aneurysms in the abdominal cavity can similarly occur in any location, such as on the abdominal aorta 1 12, the iliac arteries 114, or any vessels branching therefrom.

Aneurysms generally can occur in vessels having weakened walls. Blood pressure in such vessels can cause dilating or bulging at the weakened vessel walls, and, ultimately, the weakened walls may be overcome by the blood pressure. FIG. 2 shows an example of a vessel having a normal size or diameter 202, which can bulge or dilate at a section of the vessel having a wall weakened by a vascular disease. This weakened wall can then result in an aneurysm. An aneurysm is typically referred to by size or by an aneurysm diameter 206. Since aneurysms are typically asymmetric and non-concentric, an aneurysm size, e.g., diameter 206, can be used to refer to a dimensional distance between the vessel walls 208 affected by the vascular condition. The average normal diameter 202 of an adult human aorta, for example, ranges, on average, between 2 cm and 2.5 cm. Aneurysm diameters 206 can vary from just above the normal diameter to a size reportedly as high as 21 cm. Blood pressure acting on the affected vessel walls can further cause the aneurysm to dilate or grow until either rupture, dissection, or treatment/intervention. FIGS. 3A-3B show an example of a device that can be used for extravascular intervention. Such an extravascular intervention device 212 can provide extravascular support to weakened or otherwise affected vessel walls 208. Where the affected blood vessel has an aneurysm, the extravascular intervention device 212 can help reduce or eliminate the dilation of the aneurysm or the risk of rupture. This can be^~achieved^~with^~extravascula™ variety of ways, and, therefore, is not limited to the examples provided herein. Extravascular support can be provided, for example, with a tubular extravascular intervention device 212 that is capable of being placed to partially encircle an affected blood vessel 210 (e.g., a blood vessel having an aneurysm 210, or a portion thereof). This can provide extravascular support for, and relieve the stress on, the affected vessel walls 208. In this document, the term "around" can include "to partially encircle."

In an example, the extravascular intervention device 212 can be dimensionally configured or produced such that, when implanted around a blood vessel with an aneurysm 210, the aneurysm walls 208 can be maintained at a desired size, such as shown in the example of FIG. 3B, or can be inwardly displaced in relation to the central axis of vessel, such as shown in the example FIG. 3 A. In an example, the affected vascular walls can be maintained by dimensionally configuring the device 212 to have a size that, when implanted around the vessel or aneurysm walls 208, provides extravascular support thereto. This can help retain the affected section in a desired size — such as at the affected shape and size, e.g., the dilated shape and size of the affected section — thereby inhibiting or preventing further dilation or rupture.

In an example, the affected vascular walls can be displaced inwardly with the device 212, such as to manipulate the vessel with the aneurysm 210 toward or into a desired size, such as the size of the unaffected vessels flanking the aneurysm, e.g., the normal vessel size for the particular vessel, or any other desired shape and size. For example, the walls of an aortic aneurysm having a 6-cm aneurysm diameter 206 can be maintained at 6 cm, or displaced such as to manipulate the vessel into a substantially cylindrical shape having a diameter approximately equal to either a normal diameter of about 2-2.5 cm, or a diameter between about 2 cm and about 6 cm. In certain examples, displacement of the vascular walls, such as to significantly reduce the size of the aneurysm, may cause the aneurysm walls to fold. This could disrupt the generally circular cross-sectional geometry of the blood vessel. Accordingly, in an example, the affected vascular walls are displaced inwardly withrthe device l^^such as to^{^}provide^{^}extravascularsupportiheretσ, but without creating folds in the displaced vascular walls. In certain examples, removal or reduction of transmural stresses can cause the diameter of the aneurysm to shrink or get smaller, with or without administering therapeutic agents.

In an example, the extravascular intervention device 212 can include a structure capable of being formed into a tubular shape. Upon implantation of the device around an aneurysm, the device can form a tubular structure 213 having one or more inner surfaces 214 that come into contact with the exterior side of the aneurysm walls 216, such as to compress, or provide compressive forces for supporting, the aneurysm walls 208. The compressive forces can act on the aneurysm walls 208, such as to maintain a desired size or to displace them inwardly to produce a desired size. The longitudinal length of the device 224 can be less than, equal to, or greater than the longitudinal length of the aneurysm 204. "Longitudinal" is herein used as a directional reference that is substantially parallel with the central axis of the vessel having the aneurysm. In an example, the longitudinal length of the device 224 is greater than or equal to the longitudinal length of the aneurysm 204. This can provide support over at least the longitudinal length of the aneurysm 204.

In an example, support for the aneurysm walls can be provided with a plurality of extravascular intervention devices 212, such as implanted in a stacked arrangement. This can yield an effective longitudinal length 226 that can be less than, equal to, or greater than the longitudinal length of the aneurysm 204. A plurality of extravascular intervention devices 212, for example, can be used on an aneurysm that has one or more vessels branching therefrom. This can accommodate the branching vessels and can provide support over an effective longitudinal length 226 that is greater than or equal to the longitudinal length of the aneurysm 204. In the example of FIG. 3B, a plurality of extravascular devices 212 can be stacked in an overlapping arrangement, such as to provide contiguous support over the effective longitudinal length 204, while accommodating the branching vessels. By way of example, at least one of the devices can have an aperture 328, 330 to accommodate one or more branch vessels. In an example, one or more dilated branctrvesselsxan^~ similarlybe supported with a rsleeve,^~sucrras exiting frσnrthe aperture 328, 330. In an example, the extravascular intervention devices can be locked or otherwise coupled or attached together, such as to inhibit, prevent, or limit migration, such as after implantation. The locking or coupling mechanism can be integrated into the device itself. This can include complementary geometry for connecting or locking the ends of the devices together in a stacked arrangement. Examples can include pegs that fasten to recesses, hooks that fasten to holes, buttons, snaps, etc. In an example, the locking mechanisms can be provided separately, e.g., a plurality of devices may be sutured together longitudinally.

FIGS. 4A-4E show examples in which the extravascular intervention devices 212 can be configured or produced in a variety of shapes and sizes, such as to help retention of the corresponding vessel with the aneurysm 210 or to help manipulation of the vessel into a desired one of various shapes and sizes. For example, the extravascular intervention device 212 can be configured or produced such that its inner surfaces 214 provide a compressive force, such as to enable manipulation of the vessel with the aneurysm 210 into a cylindrical shape, a conical shape, an hourglass shape, a spherical segment shape, a curved cylindrical shape, etc.

FIGS. 4A-B show an example of a cylindrical extravascular intervention device that has a longitudinal length 224, a thickness 306, and an inner diameter 304. The longitudinal length 224, thickness 306, and inner diameter 304 can be of any combination, such as to accommodate various blood vessels and various aneurysm lengths, such as lengths of about 1 mm to about 30 cm, and inner diameters of about 3 mm to 21 cm. Lengths between about 1 cm to about 3 cm can beneficially be implanted with minimally invasive surgical procedures. Longer lengths between about 3 cm to about 12 cm or greater may require open visual surgical interventions. In an example, the device can also have one or more rounded or flared ends, such as to protect the tissue at the site of the implantation against abrasion or tearing.

In an example, an extravascular intervention device 212 can include at least one access opening 305, such as to facilitate implantation thereof around a vessel having an aneurysm 210. In an example, the access opening 305 can include a ^~~ tengthwiserliscontinuity in^~the^~generally tubular structurenf the^~device7which allows vessels to be placed through the access opening 305. Although the access opening 305 is shown by way of example as a straight line, the geometry of the opening can include any one or more of a variety of linear or non-linear shapes, including circular, parabolic, elliptical, etc. In an example, the compressive force to maintain or manipulate an aneurysm in a desired shape or size can be attained by fastening or otherwise connecting the longitudinal ends 307 of the extravascular intervention device 212 that represent the access opening, such as when placed around the vessel having the aneurysm 210, such that the ends remain essentially fixed in relation to each other. The ends can be fastened in a variety of ways, which in certain examples can depend on the materials or construction of the device 212. For example, where the device 212 is of a flexible construction, such as a fabric sheet, elastic or otherwise, and formed into a tubular structure, the longitudinal ends 307 can be fastened to each other by a suture, a self closing (e.g., dynamic or otherwise) wire, a staple, a clamp, a tie, a pin, a hook-and-loop fabric such as VELCRO^®, a zipper, a button, a snap, a hook, or any type of tension mechanism, glue/bonding agent, magnet, welding (e.g., with laser, etc.), or by any other mechanism or technique for fastening the longitudinal ends 307. In an example in which the device is constructed of a less flexible or essentially rigid material, the longitudinal ends 307 can be fixed in relation to each other with the resistance or stiffness provided by an essentially rigid construction. In an example, the extravascular intervention device 212 can include a fastener disposed thereon. The fastener can be configured such that the longitudinal ends 307 engage each other. In an example, the engagement can use an arrangement similar to tie wraps. This can help provide a device with a variable diameter, in an example. In certain examples, the longitudinal ends 307 can be fastened such that the ends butt against or overlap each other, such as shown in the illustrative example of FIG. 4B.

FIG. 4C shows an example in which the extravascular intervention device 212 (or a portion thereof) can be configured or preformed to have a generally conical or right conical shape (erg— circular or otherwise). In an example7the conical shape can generally be characterized using a minor diameter 402, a major diameter 404, and a length 224.

FIG. 4D shows an example in which the extravascular intervention device 212 (or a portion thereof) can be configured to have an inwardly or outwardly tapered shape, such as in the form of an inwardly tapered hour-glass or an outwardly tapered generally spherical segment (e.g., circular or otherwise). In an example, the shape can generally be characterized using an end diameter 406 (or different end diameters 406) and a central diameter 408. In the inwardly tapered hour-glass example, the central diameter 408 can be less than one or both of the end diameters 406. In the outwardly tapered example, the central diameter 408 can be greater than one or both of the end diameters 406.

In some examples, any of the tubular shapes (e.g., the cylindrical, conical, hour-glass, and generally spherical shapes) can be configured to assume a curved shape, such as shown in the example of FIG. 4E, which shows an example of a curved cylindrical shape. In an example, the curved shape can be characterized as having a curve radius 410, an angular measurement 412, and diameters 304 (e.g., for a curved cylinder) or diameters 402 and 404 (e.g., for a curved conical shape) or diameters 406 and 408 (e.g., for a curved hour-glass or a spherical segment shape). The curve radius 410 or the angular measurement 410 can vary, such as to accommodate or resemble the curvature of the affected blood vessel, such as in the ascending aorta, as an example. In an example, the angular measurement 410 can vary between about greater than one degree and about 360 degrees. In an example, the angular measurement 410 can vary between about 180 degrees to nearly about 360 degrees, such as to accommodate the curvature of ascending aorta or the aortic arch. FIG. 4F shows an example in which the extravascular intervention device 212 can include one or more apertures 328, 330, such as to facilitate implantation around a vessel having an aneurysm at a location with a vessel branching therefrom. For example, the extravascular intervention device 212 can include an aperture ^" communicating^" wim one or both of the circumferential ends of the tubular structure 330. In an example, the device 212 can include a central aperture 328, which can have an access opening 340, such as to accommodate a celiac trunk, a mesenteric artery, etc. "Circumferential" as used herein can refer to a direction along or offset from the circumference or perimeter of the affected vessel. As noted above, support for one or more distended branching vessels can be provided, such as by a sleeve extending from the aperture 328. The various shapes described herein can generally be combined, such as to cover most or all the aorta or other blood vessels, such as discussed below with respect to FIGS. 5A and 5B. Moreover, the various shapes can be combined, such as into a single device 212, in which the device 212 can have preformed segments, such as with the particular shapes discussed herein or otherwise. For example, the device 212 can be preformed to include a first curved shape segment, followed by a cylindrical segment, followed by a second curved shape segment, etc.

FIG. 5 A shows an example of extravascular intervention devices 212, which can be implanted around one or more blood vessels including, but not limited to, the ascending aorta 502, the arch of the aorta 504, the thoracic aorta 506, the abdominal aorta 510, and the iliac arteries 508. A plurality of relatively small extravascular devices 212 (e.g., each about 1 cm to about 2 cm in length) can be implanted in a concentrically stacked arrangement, such as shown with respect to the abdominal aorta 510. The stacked arrangement can help permit implanting the devices 212 to cover a relatively large affected vessel segment using a minimally invasive surgical procedure. The devices can be stacked to overlap each other (not shown), to butt up against each other (such as shown in FIG. 3B), or spaced apart from each other (such as shown in FIG. 5A). In certain examples, the abdominal aorta 510 and the iliac arteries 508 can both be affected by one or more aneurysms, in which case the extravascular device 212 alone (or in a plurality of devices 212) can have a "Y" shape or a portion thereof, such as to cover desired portions the various affected vessels.

FIG. 5B shows an example in which the extravascular devices 212 can be implanted in a non-concentrically stacked arrangement, such as around one or more curved^" sections of tteΕoTtaTsuclras one orTnδTeOf^scending^"aόfta^"502^ the^"afcruDf the aorta 504, or the thoracic aorta 506. In an example, a plurality of devices 212 (or a single device having a plurality of differently shaped segments) can be implanted around the affected section, such as to accommodate or conform to the curvature of the aorta. In an example, the devices 212 can be implanted around the aorta to form a curved section, such as from about 180 degrees to about 360 degrees. The degree of the curvature (or any other dimension of the affected blood vessel) can be based on actual measurement (e.g., with a CAT scan or other imaging modality that can be used to determine the dimensions of the affected blood vessel). FIG. 5B schematically shows an example of the locations for five extravascular devices or a single device with five segments 512, 514, 515, 517, and 519. In this example, the devices or segments can be implanted to accommodate or conform to the curved sections of the aorta. To conform to the curve of the ascending aorta 502, a plurality of differently shaped devices or segments 512, 514 can be used. For example, a first device 512 can include a curved section with a first curve radius 516 and length 526, and the second device 514 can include a curved section with a second curve radius 518 that is different than the first curve radius 516 and a length 528. The curved sections can be separated by a straight section 515 with a length 529. The arch of the aorta 504 can similarly be supported with one or more devices or segments 517, 519, such as having curve radii 530, 521, respectively, and a lengths 532, 523 respectively. A sleeve 534 can protrude from aperture 536, such as to accommodate the brachiocephalic trunk.

The shape or size of the device or devices selected for a particular application can be based on measured dimensions of the affected blood vessel. In an example, the measured dimensions can be communicated to a manufacturer that can then produce the at least one extravascular device 212 such that that it conforms to or resembles the desired or measured dimensions. The extravascular device 212 can, for example, be designed based on a three-dimensional representation of the affected blood vessel so as to closely resemble the shape and size of the affected blood vessel or the pre-affected (e.g., normal) shape and size of the affected blood vessel. In an example, the extravascular device can be shaped to resemble the affected blood vessel^~and to include at ^"least^" σne access^" openϊngihat ^~allowslhe^~ affected blood vessel to be placed therethrough. A plurality of differently shaped and sized devices can also be manufactured and warehoused, or packaged in kit form, such as for a particular blood vessel or for a particular aneurysm size. For example, a kit configured for the ascending aorta can include a number of curved sections and straight sections of various lengths or diameters for use with 5 cm aneurysms. In an example, a kit can be provided to include a plurality of devices that, when assembled collectively, resemble the desired shape or the affected shape of the blood vessel. In an example, the kit can include devices that collectively provide support for a curved blood vessel, such as over an angular measurement of about 180 degrees to nearly about 360 degrees. In an example, the kit can include one or more other items therein that are useful or necessary for implantation, including one or more surgical tools, one or more sutures, instructions for use (IFUs) etc.

A standard thoracotomy can leave a scar approximately 10 to 15 centimeters in length, and result in significant post-operative pain as well as potential complications such as bleeding, infection, or air leakage. The extravascular device described herein can avoid these problems, such as when it is placed via one or more small incisions, such as by using a thorascope. The present extravascular support devices can, in certain examples, be placed by a minimally invasive surgical procedure, which can sometimes help reduce or avoid the need to isolate the aorta from the structures posterior to the aorta.

The method of implanting the extravascular intervention device 212 can vary, such as depending on the location of the aneurysm. Implantation, for example, can be achieved by introducing the device to a site of interest in a patient using a minimally invasive laparascopic technique, or with open-surgical intervention. With regard to laparascopic procedures, the extravascular intervention device 212 can generally be introduced into the thoracic cavity (e.g., between a subjects ribs) or abdominal cavity through a trocar, and implanted using common laparascopic tools (e.g., by rolling or collapsing the extravascular intervention device 212 into a compact shape) and passing the device 212 through the trocar to ^{" "} the target vessel^~The^~extravascular device^~ordevrces 212 can benmplanted to^{^} provide extravascular support to a significant amount of the affected blood vessel, (e.g., the affected section of the blood vessel, such as greater than about 50% to about 100%, or greater).

In an example, the extravascular intervention device 212 can be opened or expanded, and placed around the vessel having the aneurysm. The longitudinal ends can then be connected to each other, if desired, such as to provide a compressive force to maintain or attain a desired shape or size of the aneurysm. In an example, the device can be made of a biocompatible (and, in an example, MRI compatible) material. The material can be resilient against arterial blood flow pressure and preformed into a tubular shape. The tubular shape can be resumed when the device is placed into contact with the affected blood vessel. This can allow the affected blood vessel to pass through the tubular shape. When the original tubular shape is resumed (such as via a shape-memory property), the tubular structure can provide at least a minimal amount of compressive force against the affected section of the blood vessel. This can help avoid the need for a physician to maintain the proper tubular shape while trying to connect the longitudinal ends. Self-closing or locking sutures can be made of a biocompatible (and, in an example, MRI compatible) material, resilient against arterial blood flow pressure. In an example, when heated, the suture material automatically form pigtails for knotting the sutures. In an example, the self-closing sutures can be preformed to tighten the connection between the longitudinal ends upon applying heat.

In an example, the extravascular intervention device 212, upon implantation around a vessel with an aneurysm 210, can be retained in place relative to the aneurysm at least in part by the frictional forces created between the inner surfaces 214 of the extravascular intervention device 212 and the vascular wall. In an example, the extravascular intervention device 212 can also be fastened to the patient's anatomy, as with one or more sutures or one or more staples. Alternatively, "active" fixation can be achieved with one or more internal "barbs" or by roughening the interior surface that contacts the exterior of the vascular structure.

In an example, the extravascular intervention device 212 can be constructed — of one or more of a^arietjπmaterials, which can be one or more of biocompatible^ MRI-compatible, or resilient against arterial blood flow pressure. An example can use a non-biocompatible material that is covered with a biocompatible material. In general, a biocompatible material will be acceptable for implantation in the body such that, if there is any adverse bodily reaction to the presence of the material, it is not so great as to outweigh the benefit of the device when employed for its intended use.

In an example, the device can be constructed using a metal mesh, which can have appropriate geometrical features of the mesh (e.g., sinusoidal or semi-circular mesh members, which can include a cross pattern to provide adequate flexibility). In an example, a NITINOL (a super elastic nickel titanium alloy having a shape- memory property) material can be used. In another example, another biocompatible (and, in an example, MRI compatible) material resilient against arterial blood flow pressures can be used, such as stainless steel, for example. In some examples, one or more of a non-resorbable polymer or elastomer, such as silicone, fluoropolymer, polyolephin, or polyurethane can be used. In an example, a device 212 can be fabricated from a composite of two or more different types of materials. For example, the device can be fabricated from a blood or other fluid-impermeable membrane, which can be attached to or otherwise associated with a structural frame or scaffold. Certain materials can be useful for certain uses of the device 212. In a general example, the material can include one or more materials that are biocompatible and non-toxic to the vessel about which the device is placed. In a general example, the device can be used for contacting cardiovascular vessels and therefore can include a material that provides a high degree of hemocompatibility. In a general example, the material is selected such that it does not inhibit or prevent growth of a new intima layer. The device's material can be carefully constructed to have thickness and properties appropriate to provide the stiffness and flexibility desired for the particular vessel about which the device is placed. Because artery walls undergo ongoing dilatation and contraction (e.g., due to the systole and diastole of the heart), the device can be constructed to be flexible enough such that it^~

In an^" example; the^~device can be constructed to reduce or avoid any adverse inflammatory or immune response. In an example, the device can be constructed such that it does not present protrusions or disruptions to blood flow through the vessel about which the device is placed. This can help reduce the likelihood of forming blood clots. Some examples of such materials for use in constructing the device 212 can include, without limitation, graft material and a shaped memory alloy (SMAs) such as a synthetic polymer, metal, alloy, polyester, Dacron, Gortex, polytetrafluoroethylene, polyethelene, polypropylene, polyurethane, silicone, stainless steel, titanium, platinum, combinations thereof, etc. In some examples, the extravascular device can be made of one or more of a shape memory alloy (SMA) or a combination of a graft material and a SMA. SMAs are a group of materials that demonstrate a shape-memory property, which can be described as an ability to return to some previously defined shape or size, such as when subjected to an appropriate thermal procedure, in certain examples. Generally, SMAs can be plastically deformed and, upon exposure to thermal or other suitable manipulation, will return to the pre-deformation shape. Some SMA material is considered to be two-way shaped memory alloys because they will return to the deformed shape upon proper thermal activation. Examples of some SMAs can include Ag-Cd alloys, Cu-Al-Ni alloys, Cu-Sn alloys, Cu-Zn alloys, Cu-Zn- Si alloys, Cu-Zn- Sn alloys, Cu-Zn- Al alloys, In-Ti alloys, Ni-Al alloys, Ni-Ti alloys (e.g., available under the trade name NITINOL), Fe-Pt alloys, Mn-Cu alloys, Fe-Mn- Si alloys, or the like.

The selection of materials for the device 212 can be based upon the mechanical and physical properties needed for the intended use. In an example, the material can be MRI "compatible," such that it can be adequately imaged using MRI without presenting appreciable artifact or safety issues. Examples of suitable materials can include those that can overcome magnetic attraction of magnetic members, RF heating effects of conductive members, and provide accurate visualization under MRI. Some examples of suitable MRI compatible materials can include, but are not limited to, an engineering resin such as polysulfone, polyethylene fiberroptical fiber, fiberglassrand a carbon frber-epoxyxomposite.

In an example, material of the device can be selected based on the properties thereof, e.g., the modulus of elasticity, the tensile strength, etc., in relation to the desired characteristics of the tubular structure of the device, e.g., flexibility, elasticity, etc. Biocompatible (and, in an example, MRI compatible) shape-memory material resilient against arterial blood flow pressures can be selected at least in part based on a transition temperature at which the material returns to its preformed shape. In an example, the device material can be constructed into a woven fabric, mesh, or sheet, or a combination thereof, that can be formed into a tubular structure that it is capable of being implanted around the vessel with the aneurysm 210. In an example, the extravascular intervention device 212 can include a biodegradable or biosorbable material, such as PGA (Polyglycolic Acid), PLA (Polylactic acid), or a co-polymer of the two, that can wear away, such as when no longer needed or desired. In an example, the device can degrade upon completing the desired treatment (e.g., when the aneurysm walls have been thickened, with or without a therapeutic agent, sufficient to limit or prevent further dilation of the aneurysm). In an example, the material is selected to provide enough strength to resist against significant deformation when exposed to systolic blood pressure.

FIGS. 6A-6B show an example of a collapsible extravascular intervention device. In this example, the extravascular intervention device 600 can be collapsed, such as for introduction into the target cavity, and then expanded, automatically or otherwise, such as for implantation around the vessel with the aneurysm 210. Collapsibility can be provided in a variety of ways, such as with a device formed from a loosely woven fabric or netting. In the example of FIGS. 6A-6B, collapsibility can be provided with a device 600 having a plurality of longitudinal members 602, 604, which can be connected to each other, such as with a plurality of flexural members 606, 608. In this example, each of the flexural members 606, 608 can have a bend 610, 612 that, upon application of an appropriate force, provides flexure. This results in the narrowing of the lateral distances 616, 618 between the longitudinal members 602, 604, and the corresponding narrowing of the overall circumferential length 650 and diameter 630 of the device 600. In an example, the extravascular intervention device 600 correspondingly expands teτg:7 witrror without the application of force), such as to increase the lateral distances 616, 618 between the longitudinal members 602, 604. In an example, this can yield a desired overall circumferential length 650 or diameter 630 to substantially match the circumference and diameter of the desired shape and size of the affected vascular walls. In an example, the device can have a preformed tubular shape that expands when the device is placed into contact with the affected blood vessel.

The number or dimensions of the longitudinal members 602, 604 or of the flexural members can vary, such as according to the shape or size of the targeted vessel or its desired shape or size to be obtained by the device. In an example, the device can comprise two end longitudinal members 604 and a plurality (e.g., five) of central longitudinal members 602. In an example, each longitudinal member 602, 604 includes a first end and a second end connected by respective flexural members to an adjacent longitudinal member's first end and second end 606, 608, respectively. The number of central longitudinal members 602 can vary (e.g., such as between about 3 and about 3000 or greater) such as based on the vessel diameter at the location of interest, the desired amount of support to be supplied thereto.

The thickness of the device 652 can vary, for example, depending on one or more properties of the material from which the device is constructed. In an example, the widths 620, 622, 624 of the longitudinal members 602, 604 and the flexural members 606, 608 can vary depending on the properties of the materials, the desired flexibility or elasticity for collapsing and expanding the device 600, and the desired amount of support that the device provides to the aneurysm vessels. Greater support can use larger widths, which can limit or reduce the amount of unsupported space between the longitudinal and flexural members. In an example, the end longitudinal members 604 can include corresponding interlocking geometries that allow the longitudinal ends 604 to engage each other. This can help restrict longitudinal movement. The interlocking geometries can be provided, in an example, by one or more keys disposed on one of the end longitudinal members 604 and a corresponding receiving geometry on the opposing longitudinal end member. The interlocking geometries can allow a plurality of ^{" ~} extravascϋlardevices 600 to be fastened fireacb ; other, suchras toTncreaseihe circumferential length 650. As described above, extravascular intervention devices 600 can be longitudinally stacked, such as to yield a desired effective longitudinal length or to accommodate one or more vessels branching from the aneurysm or other location on the vessel. In an example, the flexural members 606, 608 can further include at least one flexible element, as at the bends 610, 612. A flexible element can provide additional flexibility to the flexural members. This can help the flexural members 606, 608 to behave elastically, such as when the extravascular intervention device 600 is collapsed, such as when subjected to stresses below the device material's elastic limit. This allows the device to expand and return substantially to the original un-collapsed orientation, such as upon removal of a compressive collapsing force acting on the device 600.

FIG. 6C shows an example in which a flexible element 641 can include a roughly semicircular element that includes an obtuse circumferential geometry 661 and an acute circumferential geometry 662. In this example, "Obtuse" pertains to the side of the flexible element facing the obtuse angle created by the bend 610, and "acute" pertains to the side of the flexible element facing the acute angle created by the bend 610. The obtuse and acute circumferential geometries 661,662 generally can include a plurality of arcs that define the roughly semicircular flexible element 641. Additional material can be provided in areas of the flexible element 641 where localized stress concentrations can occur, such as at the bend 610 or at the intersection of the longitudinal members 602, 604 and the flexural members 606, 608.

In an example, the obtuse circumferential geometry 661 can include a pair of first central arcs 644 having centers that can be separated by a first central distance 645. In an example, the first central arcs 644 can interface with the flexural members 606, 608, such as by a pair of first exterior arcs 643, which can be tangential to both the first central arcs 644 and the flexural members 606, 608. In an example, the acute circumferential geometry 662 can include a pair of second central arcs 642, which can interface with the flexural members 606, 608, such as by a pair of second ^"exterior arcs 64Θ.^{^}Fhe^~centers of the secondxentraharcs can be separated by a second central distance 672. The second exterior arcs 640 can intersect tangentially with the second central arcs 642; however, they do not do so with respect to the flexural members 606, 608 in this example, thereby creating a protruding section of additional material at the second exterior arcs 640. The "center of an arc" can be conceptualized as the origin of the radius of the arc. Additionally, "separated" as used herein can be conceptualized as a lateral or circumferential distance between the centers of the arcs. In an example, the distance between the centers of the arcs can be a negative number, as with the acute circumferential geometry, such that the radii of the central arcs can overlap. In an example, the distance between the centers of the arcs can also be a number greater than or equal to zero, such as with the obtuse circumferential geometry, such that the radii of the central arcs can either coincide or do not overlap.

As described above, the device 600 can be implanted with a minimally invasive endoscopic (e.g., thoracoscopic) technique or with open-surgical intervention. In an endoscopic example, the extravascular intervention device 212, 600 can be generally introduced into the target cavity through a trocar in a collapsed configuration, thereby allowing the device 212, 600 to fit within or on the trocar. Upon insertion in the target cavity, the extravascular intervention device 212, 600 can then be unfolded, expanded, or otherwise opened, automatically or otherwise, such as to permit the device 212, 600 to be placed around the affected vessel in a manner forming a tubular structure.

FIG. 7 shows an example in which the extravascular intervention device 600 can be implanted around the vessel after placing a base material 700 (e.g., in the form of a sheet, mesh, or fabric, such as Dacron) around the affected vessel. This can help inhibit or prevent the vessel from bulging out of the apertures formed between the flexural and longitudinal members 606, 608, 602. In an example, the base material 700 can be placed loosely around the affected section of the vessel and held in place with the intervention device 212, 600 or the like. The base material 700 can be fastened at longitudinal ends to provide additional support to the aneurysm, or connected to the interventional device 212, 600 or the like. Irran example, the base material"700 or the interventional device 212^600 or the like can include, or be impregnated with, one or more of a therapeutic agent, a pharmacological or biologic agent, a medicine or other composition. This can permit acute or sustained release extravascular administration of the desired agent or composition to the affected blood vessel. Some examples of pharmaceutical agents can include, without limitation, a composition comprising a therapeutic agent for use in stimulating or inhibiting vascular growth (e.g., smooth-muscle-cell- proliferation), such as to increase the thickness of the affected blood vessel or to promote surface scarring or retraction of the affected blood vessel. The dispensed composition can comprise any other type of therapeutic agents. Some examples of therapeutic agents can include, by way of example, but not by way of limitation, sirolimus, everolimus, or any other related composition, paclitaxel, basic fibroblast growth factor, dexamehasone, abciximab, or another Ilb/IIIa antagonist, angiopeptin, TGF, tetracycline, or another sclerosing agent, fullerenes, etc. The compositions, with or without timed-release mechanisms, can be coated directly onto at least a portion of the inner surface or the outer surface of the device for administration of the therapeutic agent, with or without providing extravascular support to a vessel.

As described above, endovascular graft implants can have a tendency to migrate, such as downstream in the direction of blood flow. Endovascular implant migration is sometimes unpredictable. It is difficult to attribute endovascular implant migration to any particular factor that would prompt a physician to monitor the implant for migration. Therefore, physicians typically monitor implant migration for all endovascular implant patients. In an example, the extravascular devices described herein can be used to extravascularly stabilize an endovascular graft implant. For example, the extravascular device can be implanted around the affected blood vessel, such as to compress the endovascular implant to inhibit, prevent, or limit migration. In an example, an extravascular support such as described herein can be used to help secure an endovascular graft (endograft) by implanting at least one extravascular support at or near a proximal segment of the endograft, and another extravascular support at or near a distal (downstream) ^~~ segfnenTof the^rϊdogfaftr This can limtt^ertain^"erMoτascϋlar^"te^"afeτιndiτihibit endograft upstream or downstream migration. In an example, a downstream extravascular support at or near the distal segment of the endograft can be used without an accompanying upstream extravascular support, such as to limit downstream migration of the endograft. As described above, it can be desirable to use a minimally-invasive surgical technique (which is less invasive than open surgery) to place the extravascular support to at least partially encircle an aneurysm of a blood vessel. In an example, the minimally-invasive surgical technique can include placing the extravascular support device using two small holes in the patient's chest — such as on opposing sides of a target vessel of interest. In an example, the extravascular support can include a sheet of material that self-curls, such as shown in FIG. 4A. Such an extravascular support sheet can be partially or fully uncurled during insertion, such as to receive the target vessel therewithin, or to manipulate the extravascular support sheet to a desired location. An example of a potential difficulty in placing the extravascular support about a target region of an aorta, for example, can arise from the fact that other nearby vulnerable vessels should be avoided during the procedure. For example, portions of the pulmonary artery can be located relatively close to portions of the aorta. Neither the pulmonary artery nor the aorta should be pierced or otherwise damaged while placing the extravascular support. The present inventor has recognized, among other things, that it can be useful to provide a device or method to help guide or place an extravascular support (such as for treating an aortic or other aneurysm), such as during minimally invasive surgery.

FIG. 8 shows an example of an extravascular support sheet 800, which is normally curled such as shown in FIG. 4A. However, in the example of FIG. 8, the support sheet 800 has been pulled flat. In this example, the sheet 800 can include couplings 802A-D. In an example, such couplings 802A-D can include four holes, which can be located near the four corners of the uncurled extravascular support sheet 800. In this example, the uncurled sheet 800 can have a length 806, a width 804, and a thickness 808. In the example shown in FIG. 8, the hole couplings 802A ^{" "}Mϊd^2B^~cmrbe^"separate(i^~frσm^"each^" other (wherrthe^"sheet^"8ΘO is uncurled) by a distance that is about equal to (slightly less than) the width 804, and holes 802C and 802D can follow similarly. The hole couplings 802A and 802C can be separated from each other by a distance that is about equal to (slightly less than) the length 806, and hole couplings 802B and 802D can follow similarly. In an example, a guiding member 81 OA, 81 OB, 81 OC, or 81 OD can be attached to a respective one of the couplings 802A-D. This can be accomplished, in an example, by threading a guiding member 81 OA-D through a hole provided by the corresponding coupling 802A-D. The illustrative example of FIG. 8 shows optionally end-looped guiding members 81 OA-D, which can be attached noose-like to their respective couplings 802A-D. This can be accomplished, in an example, by threading the guiding member 81 OA-D through the hole provided by that particular coupling 802 A-D and also threading through the guiding member's end loop. The example of FIG. 8 showing end-looped guiding members 81 OA-D, however, is just one illustrative example — several other examples of other configurations of the guiding members 81 OA-D are also described below.

In an example, the guiding members 81 OA-D can be pulled apart in desired directions. This can help provide tension that can uncurl the sheet 800, such as during minimally invasive guidance or placement of the sheet 800. In an example, the guiding members 81 OB and 81 OD can serve as leading members, which can be used to pull a leading edge of the uncurled sheet 800 through a critical region of interest (such as a region between an aorta and a pulmonary artery) during minimally invasive surgery. In such an example, the guiding members 81 OA and 81 OC can serve as trailing members, which can be used to provide a desired level of tension to a trailing edge of the sheet 800. Such tension can help uncurl the sheet 800 (or to maintain the sheet 800) uncurled, such as while it is being pulled through a critical region, such as the region between the aorta and the pulmonary artery. In a minimally invasive surgical example, the leading members can be introduced into a first hole in the chest (e.g., located on a first side of a target blood vessel of interest) and guided through the critical region (e.g., between the aorta and the pulmonary artery). Then, the leading members can be withdrawn through a ^" second hole in the^~chest (e^"g:^~locate^"d on an a second side^~of^"the target blood vessel of interest, opposite from the first side, beyond the critical region through which the sheet 800 is to be passed). Then, the sheet 800 can be passed through the critical region, such as by pulling on the leading members while holding the trailing members so as to maintain a desired amount of tension on the sheet 800 to keep the sheet 800 uncurled, such as during guiding of the sheet 800 to a location adjacent to the target blood vessel of interest. Then, the guiding members 81 OA-D can be detached from the sheet 800, such as to permit the sheet 800 to curl at least partially about the aneurysmic target vessel, such that the curled sheet 800 provides exovascular support to the aneurysm, such as to limit its expansion, or to promote its contraction.

In an example, the guiding members 81 OA-D can be detached from the sheet 800 by providing a specified breakaway portion of the guiding member 81 OA-D. In an example, such a breakaway portion can include a specified weakened region of the guiding member 81 OA-D. In such an example, when the guiding member 810A- D is pulled with a force that exceeds a breakaway force, the guiding member separates at the location of the breakaway portion.

In another example, the guiding members can be detached from the sheet 800, such as after placement about an aneurysm, such as by using a minimally invasive instrument to grasp or catch the end loop of the guiding member 81 OA-D, and to then retract the end loop of the guiding member 81 OA-D, such that the end loop slips along its guiding member 81 OA-D in a reverse threading (unthreading) process, thereby detaching the guiding member 810 from the sheet 800. However, the guiding members 81 OA-D need not include looped ends. In various examples, the guiding members 81 OA-D can include a vascular tie, a wire or any rail-like structure, a metallic structure, a suture, or the like. Also, fewer than four guiding members 81 OA-D can be used, depending on the tendency of the sheet 800 to curl, and the geometry of the region through which the sheet 800 is to be passed during insertion and placement of the extravascular support sheet 800 curled around an aneurysmic vessel.

FIG. 9 shows an illustrative example of a distal end-view of an elongated guiding member 900, whiclrincludes a male^~snap-fϊtting 902, such as caninclude a shaft 904 and a protuberance 906. In an example, the snap-fitting 902 can be snap- fitted into a respective hole coupling 802. These snap-fit connections between the guiding members 81 OA-D and the sheet 800 can provide enough connective resistance to allow the uncurled sheet 800 to be pulled through a critical region of interest, such as described above, but can release when a stronger force is exerted, such as to allow the sheet 800 to remain in place and to curl around the aneurysm of the target vessel.

FIG. 10 shows another example in which the guiding members 1010A-D can include a single suture thread that is looped through the corresponding hole coupling 802A-D, drawn back, and optionally knotted, such as to form a loop. When the uncurled sheet 800 has been guided to the region of interest, the knotted guiding member 101 OA-D loop can be cut, and a single end pulled back to withdraw the guiding member 101 OA-D.

FIG. 11 shows an example in which a pair of guiding members 1100A-B can be laced through the sheet 800. For example, the guiding member 1 10OA can be laced through the hole couplings 802A-B, and the guiding member 1 10OB can be laced through the hole couplings 802C-D. Pulling the two ends of each of the guiding members 1100A-B taut will uncurl the sheet 800, such as for minimally invasive guidance or placement about an aneurysm. Although the illustrative examples shown in FIGS. 8-11 depict a relatively solid extravascular aneurysm support sheet 800, the couplings 802 and guiding members 810, 900, 1010, and 1 100 can also be used in conjunction with a scaffold- like extravascular aneurysm support sheet, such as shown in FIG. 6A. In an example, the gaps between the solid struts can serve as the couplings 802. In another example, eyelets or other structures can be formed to provide specifically- sized receptacles, such as to provide a desired fit (e.g., snap-fit, threaded-fit, etc.) with a particularly selected guiding member.

In an example, one or more of the guiding members 1100 A-B can include or be provided with one or more knots, such as at one or more of knot locations 1102A-D. A knot can be formed by knotting the guiding member 1100A-B one or more times. The knot can be large enough such that the knot cannot slip through the corresponding nearest hole coupling 802A-D. In this way, one or more knots at the one or more knot locations 1102A-D can be used to help position the sheet 800, such as by pulling the guiding member 1 100A-B such that the knot pulls against the nearby corresponding hole coupling 802A-D. This can help pull the sheet 800. In an example, the knot locations 1102A-D can be positioned, such that there is enough distance between the knot locations 1102A-D and the corresponding hole coupling 802A-D to allow the knot to be untied. Untying allows the corresponding guiding member 1100A-B to be pulled through, such as when the sheet 800 has been positioned as desired. This can release the sheet 800 from the corresponding guiding member. For example, if the guiding member 1100 A includes knots on both sides of the sheet 800, then the space between the knot locations 1102A, 1102D can be enough such that if the knot at the knot location 1 102D is pulled up against the hole coupling 802A, the knot at the knot location 1102A can be positioned such that the user can untie it. In an example, the knot at the knot location 1102 A can be positioned beyond the minimally-invasive opening, allowing the untying. However, this is not a requirement. In an example, the knot at the knot location 1102A can be untied while positioned internally, such as by using a minimally-invasive instrument to assist in untying the knot. In an example, the knot need not be untied — instead, the guiding member 1100A-B can be cut or otherwise separated at a location between the knot locations 1102A, 1102D, such as to allow the guiding member 110OA to be pulled through to release the sheet 800. In another example, the separation can be obtained by providing a specified breakaway location about which the member 110OA is configured to break apart when forces on opposing sides of the breakaway location exceed a specified value. FIG. 12 shows an example of an extravascular aneurysm support sheet 1200, similar to that shown in FIG. 6 A, but including resilient hook couplings 121 OA-D at its four corners. In this example, each hook coupling 121 OA-D forms a corresponding opening 1212A-D, through which a guiding member can be passed. In ^"an exanϊple,Trϊe^~distal^~erϊd of each gUicting member carf have a knoTόr other^~ widened portion that can seat against the corresponding resilient hook coupling 121 OA-D. The proximal ends of the guiding members can be pulled back to uncurl the extravascular support sheet 1200, such as during guiding or placement during minimally invasive surgery. When the proximal end of the guide member is pulled using a force above a specified threshold value, the corresponding one of the resilient hook couplings 121 OA-D can deform so as to open and release the knot or other widened distal end of the guiding member. In this way, the guiding members such as described above can be used with the scaffolded extravascular support sheet 1200 to guide or place the extravascular support sheet 1200 about an aneurysm of a target blood vessel of interest.

Although the above examples in FIGS. 8-12 have shown various guiding members and various couplings, the different examples of guiding members or couplings can be used with each other in various permutations or combinations. In certain examples, a kit can be provided, such as with a useful permutation or combination of guiding members or extravascular support sheets or both. In certain useful examples, an extravascular support sheet can be provided with one or more of the guiding members already in place, e.g., already attached to the extravascular support sheet, such that they are conveniently ready for use, such as with a minimally-invasive or other surgical technique. In certain examples, these components can be single-use disposable devices. In certain examples, these components can be pre-sterilized and packaged in a sterile package. In certain examples, these guiding members and extravascular support sheets can be provided together with instructions for use (IFUs), such as in conjunction with a minimally invasive or other surgical technique. Although the present devices and methods have particularly emphasized examples useful for treating aortic aneurysms, they are not so limited, and can be applied to the treatment of other types of aneurysms and other vascular conditions.

Additional Notes The above^~detailed descriptiorilncludes^{^} references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as "examples." Such examples can include elements in addition to those shown and described. However, the present inventors also contemplate examples in which only those elements shown and described are provided.

All publications, patents, and patent documents referred to in this document are incorporated by reference herein in their entirety, as though individually incorporated by reference. In the event of inconsistent usages between this document and those documents so incorporated by reference, the usage in the incorporated reference(s) should be considered supplementary to that of this document; for irreconcilable inconsistencies, the usage in this document controls.

In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a nonexclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In the appended claims, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, that is, a system, device, article, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Method examples described herein can be machine or computer- implemented at least in part. Some examples can include a computer-readable medium or machine-readable medium encoded with instructions operable to configure an electronic device to perform methods as described in the above examples. An implementation of such methods can include code, such as microcode, assembly language code, a higher-level language code, or the like. Such code can include computer readable Instructions for performing various methods. The code may form portions of computer program products. Further, the code may be tangibly stored on one or more volatile or non- volatile computer-readable media during execution or at other times. These computer-readable media may include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., compact disks and digital video disks), magnetic cassettes, memory cards or sticks, random access memories (RAMs), read only memories (ROMs), and the like.

The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. §1.12Qo), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

WHAT IS CLAIMED IS:

1. A device comprising: an extravascular support sheet, sized and shaped to permit placement at least partially around a blood vessel of a human or animal subject, the support sheet comprising a thickness, a width, and a length, wherein the length is configured to extend longitudinally along the blood vessel, wherein the width is configured to extend at least partially around the blood vessel, and wherein the sheet is capable of providing a longitudinal opening to accept the blood vessel within an at least partially enclosed interior region provided by the sheet; and first and second couplings separated from each other along the sheet by at least a substantial portion of the width, the first coupling configured to be coupled to a leading member during the placement of the sheet at least partially around the blood vessel, the second coupling configured to be coupled to a trailing member during the placement of the sheet at least partially around the blood vessel.

2. The device of claim 1, comprising third and fourth couplings separated from each other by at least a substantial portion of the width, the third coupling configured to be coupled to a leading member during the placement of the sheet at least partially around the blood vessel, the fourth coupling configured to be coupled to a trailing member during the placement of the sheet at least partially around the blood vessel; and wherein the first and third couplings are separated from each other by a substantial portion of the length, and the second and fourth couplings are separated from each other by a substantial portion of the length.

3. The device of claim 2, wherein at least one of the first, second, third, and fourth couplings comprises a hole extending through the sheet.

4. The device of claim 3, wherein the hole is sized and shaped to receive at least one of the leading member or the trailing member through the hole.

5. The device of claim 1, further comprising at least one of the leading member or the trailing member.

6. The device of claim 5, wherein at least one of the leading member or the trailing member comprises a specified breakaway location about which the member is configured to break apart when forces on opposing sides of the breakaway location exceed a specified value.

7. The device of claim 5, wherein the sheet and the at least one of the leading member or the trailing member are provided together in a kit.

8. The device of claim 5, wherein the at least one of the leading member or the trailing member includes at least one of a loop, a knot, a widened portion, or a snap- fitting.

9. The device of claim 1, wherein the sheet is deformable and comprises a shape-memory property such that, when released from being deformed, the sheet tends to resume its previous shape before being deformed, and wherein the first and second couplings are located on the sheet so as to tend to flatten the sheet when the leading member and the trailing member exert opposing forces on the first and second couplings.

10. The device of claim 9, wherein the sheet comprises a deformable scaffold that comprises the shape-memory property.

11. The device of claim 1 , further comprising first and second fasteners, separated from each other by at least a substantial portion of the width, the first and second fasteners configured to be coupled to each other to secure the sheet in place at least partially around a blood vessel.

12. The device of claim 1, wherein at least one of the first or second couplings comprises a resilient hook configured to receive and retain a guiding member, and to release the guiding member when a force exceeding a threshold value is applied to the guiding member.

13. A method comprising: providing or using an extravascular support sheet, sized and shaped to permit placement at least partially around a blood vessel of a human or animal subject, the support sheet comprising a thickness, a width, and a length, wherein the length is configured to extend longitudinally ajong the blood vessel, wherein the width is configured to extend at least partially around the blood vessel, and wherein the sheet is capable of providing a longitudinal opening to accept the blood vessel within an at least partially enclosed interior region provided by the sheet; and providing or using a first leading member and a first trailing member capable of being associated with the sheet at locations that are separated from each other by at least a substantial portion of the width.

14. The method of claim 13, comprising: attaching the first leading member to a first coupling associated with the sheet; attaching the first trailing member to a second coupling associated with the sheet; and wherein the first and second couplings are separated from each other by at least a substantial portion of the width.

15. The method of claim 14, comprising placing the sheet into position at least partially around the blood vessel, including applying opposing forces to the first leading and first trailing members to open the sheet while placing the sheet, then releasing the opposing forces to allow the sheet to self-close at least partially around the blood vessel.

16. The method of claim 15, comprising: attaching a second leading member to a third coupling associated with the sheet; attaching a second trailing member to a fourth coupling associated with the sheet; wherein the third and fourth couplings are separated from each other by at least a substantial portion of the width; wherein the first and third couplings are separated from each other by at least a substantial portion of the length; and wherein the second and fourth couplings are separated from each other by at least a substantial portion of the length.

17. The method of claim 16, wherein placing the sheet into position at least partially around the blood vessel includes applying opposing forces to the second leading and second trailing members to open the sheet while placing the sheet, then releasing the opposing forces to allow the sheet to self-close at least partially around the blood vessel.

18. The method of claim 16, comprising providing at least one of: (1) the first leading member and the first trailing member as a single flexible member extending through holes provided by the first and second couplings; or (2) the second leading member and the second trailing member as a single flexible member extending through holes provided by the third and fourth couplings.

19. The method of claim 13, comprising tying the first leading member or the first trailing member to a location associated with the sheet.

20. The method of claim 13, comprising breaking apart at least one of the first leading member or the first trailing member after the sheet has been placed into location at least partially around the blood vessel.

21. The method of claim 13, comprising separating the vessel about which the sheet it to be at least partially positioned from a nearby vessel by introducing the leading member therebetween.

22. — The method of claim 13, comprising introducing the sheet, the first leading- member, and the first trailing member into the subject using a minimally invasive surgical technique that includes using first and second extravascular portals into the subject located on opposing sides of the vessel about which the sheet is to be at least partially positioned.

23. The method of claim 13, comprising providing instructions for using the extravascular support sheet.

24. The method of claim 13, comprising snap-fitting the first leading member or the first trailing member to a location associated with the sheet.

25. The method of claim 13, comprising releasing the first leading member or the first trailing member from the sheet by applying a force exceeding a threshold value to deform a resilient portion of the sheet.

26. The method of claim 13, wherein providing or using a first leading member and a first trailing member capable of being associated with the sheet at locations that are separated from each other by at least a substantial portion of the width comprises using a unitary member as both the first leading member and the first trailing member.

27. The method of claim 13, comprising: forming a knot in at least one of the first leading member or the first trailing member; and using the knot to pull against the support sheet to help position the support sheet.

28. The method of claim 27, comprising: untying the knot and then releasing the support sheet from at least one of the first leading member or the first trailing member.