Patent ID: 12193955

DETAILED DESCRIPTION

The presently disclosed subject matter now will be described more fully hereinafter with reference to the accompanying Drawings, in which some, but not all embodiments of the presently disclosed subject matter are shown. Like numbers refer to like elements throughout. The presently disclosed subject matter may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Indeed, many modifications and other embodiments of the presently disclosed subject matter set forth herein will come to mind to one skilled in the art to which the presently disclosed subject matter pertains having the benefit of the teachings presented in the foregoing descriptions and the associated Drawings. Therefore, it is to be understood that the presently disclosed subject matter is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims.

In some embodiments, the presently disclosed subject matter provides branched stent grafts and a stent graft delivery system for, and methods of, endovascular repair of aortic aneurysms including abdominal and thoracic aortic aneurysms. Embodiments of the branched stent grafts include, but are not limited to, branched aorto-uni-iliac (AUI) stent grafts, branched bifurcated stent grafts, and branched thoracic stent grafts.

The presently disclosed branched stent grafts and stent graft delivery system and methods enable the surgeon to deliver a stent graft to exclude a juxtarenal/pararenal abdominal aortic aneurysm deemed appropriate for treatment by the treating physician. Features of the stent graft delivery system include, for example, (1) a multi-functional sheath through which the branched stent grafts can be delivered into the correct anatomic position, (2) bendability via a steering mechanism at the handle that aids with precise positioning, and (3) the capacity to deliver one or more smaller sheaths for the cannulation of renal arteries and the subsequent delivery of covered stents.

In some embodiments, the branched stent grafts comprise one or more retrograde internal branches. The internal branches are flared with a larger diameter as they meet the main body of the branched stent graft to provide greater freedom to select renal arteries of a variety of anatomic configurations. The retrograde-facing branches are prewired to enable expedient cannulation of arteries.

In other embodiments, the branched stent grafts comprise one or more external branches. Likewise, the external branches are prewired to enable expedient cannulation of arteries.

The stent graft delivery system comprises a larger directional sheath for positioning the branched stent grafts and one or more smaller sheaths for the delivery of covered stents for the complete exclusion of juxtarenal/pararenal abdominal aortic aneurysms. Each of these smaller sheaths (i.e., 7 French) consists of a dilator tip which is a shaped 5 to 8 millimeter compliant balloon that, when inflated, assists with the tracking and deliverability of covered stents into the renal artery. Additionally, these smaller sheaths are delivered via a larger stent graft sheath (i.e., 18 to 20 French).

The presently disclosed stent graft delivery system and methods provide a means to deliver a branched stent graft that has internal retrograde branches or external branches, which are prewired for the expedient cannulation and delivery of covered stents to one or more arteries, thereby creating a reliable proximal seal for the exclusion of juxtarenal/pararenal abdominal aortic aneurysms. The directional sheath of the main body of the branched stent graft affords accurate stent graft delivery due to its capacity to conform to the tortuosity of the native aortic neck via a control handle at the base of the sheath, a characteristic not currently a property of stent grafts currently available. Over the wires that already cannulate the retrograde internal branches (i.e., prewired) or external branches, the smaller sheaths with compliant balloon dilator tips are introduced through the stent graft sheath via a silicone ring also located at its base. Therefore, using the presently disclosed stent graft delivery system and methods for the endovascular repair of a juxtarenal/pararenal abdominal aortic aneurysm, the branched stent grafts may be delivered through single femoral access, also not currently available in the current United States market.

FIG.1shows perspective views of two examples of conventional abdominal stent grafts. For example,FIG.1shows a stent graft100, which can be, for example, a standard tubular-shaped aorto-uni-iliac (AUI) stent graft.FIG.1also shows a bifurcated stent graft110, which can be a standard bifurcated stent graft that includes, for example, a main body112, a first limb (or leg)114, and a second limb (or leg)116. Namely, first limb114and second limb116extend from the proximal end of main body112, wherein first limb114is longer than second limb116and second limb116is designed to receive a stent graft extension120.

Generally, a stent graft is a synthetic fabric tube (graft) supported by a metal scaffold (stent). In these examples, stent graft100and bifurcated stent graft110are “covered” stents, meaning that stent graft100and bifurcated stent graft110are formed of tubular metal webs covered by woven polyester material.

A drawback of conventional abdominal stent grafts, such as stent graft100and bifurcated stent graft110, is that they must be custom-built for each patient based on preoperative computed tomographic studies, a time-consuming and costly process. Further, anatomic features, as well as design constraints of the conventional abdominal stent grafts themselves (e.g., not placing fenestrations across device struts), limit the surgeon's capability to accurately deliver these devices.

FIG.2is a perspective front view and a perspective side view of a branched main body stent graft200, which is one example of the presently disclosed branched abdominal stent grafts that comprise one or more internal branches. In this example, branched main body stent graft200comprises a main body210. Main body210is a flexible tubular-shaped stent, which is a tubular metal web covered by a woven polyester sleeve. Accordingly, branched main body stent graft200is a covered stent. Main body210of branched AUI stent graft200has a distal end212and a proximal end214. Branched main body stent graft200comprises at least one internal branch220inside main body210. In the example shown inFIG.2, branched main body stent graft200comprises two internal branches220. However, this is exemplary only. Branched main body stent graft200can comprise any number of internal branches220.

Each of the internal branches220is a flexible tubular-shaped member constructed, for example, of a nitinol skeleton covered with an expanded polytetrafluoroethylene covered stent. A distal end222of internal branch220is mated to or otherwise coupled to a fenestration or opening (seeFIG.4andFIG.5) in the wall of main body210of branched main body stent graft200. A proximal end224of internal branch220is free hanging inside main body210.

Each of the internal branches220is tapered from distal end222to proximal end224. Namely, distal end222has a larger diameter than proximal end224. That is, distal end222is a flared end of internal branch220. For example,FIG.3shows more details of an internal branch220of the presently disclosed branched abdominal stent grafts, such as branched main body stent graft200. Internal branch220has an overall length L. Distal end222of internal branch220has a diameter d1and proximal end224has a diameter d2. In one example, the length L of internal branch120can be from about 40 mm to about 50 mm. To achieve the taper, the diameter d1of distal end222can be about twice the diameter d2of proximal end224. In one example, the diameter d1of distal end222is from 10 mm to about 12 mm, while the diameter d2of proximal end224is from about 5 mm to about 6 mm. Each internal branch220can be marked, for example, with a gold marker in the form of a “P” (not shown) to aid with accurate positioning of the internal branch220in relation to the target visceral artery.

FIG.4andFIG.5are a top down view and side view, respectively, of distal end222of branched main body stent graft200shown inFIG.2and shows yet more details of an example of internal branch220. In particular,FIG.4andFIG.5shows distal end222of internal branch220mated to or otherwise coupled to a fenestration or opening230in the wall of main body210of branched main body stent graft200. For example, distal end222of internal branch220is aligned with fenestration or opening230and then sutured, woven, or adhered to the wall of main body210in the area around fenestration or opening230.

FIG.2additionally shows a guide wire250of an endoscopy system (not shown) can run through main body210of branched main body stent graft200. Namely, guide wire250enters proximal end214and exits distal end212of main body210. In similar fashion, another guide wire255of an endoscopy system (not shown) can run through internal branch220inside main body210of branched main body stent graft200. Namely, guide wire255enters proximal end224and exits distal end222of internal branch220. Guide wire250running through main body210can be a larger diameter wire than guide wire255running through internal branch220. For example, guide wire250can be the guide wire in an 18 to 20 French stent graft sheath, while guide wire255can be the guide wire in a 7 French stent graft sheath.

FIG.6shows a perspective front view and a perspective side view of a branched bifurcated stent graft600, which is another example of the presently disclosed branched abdominal stent grafts that comprise one or more internal branches. Namely, branched bifurcated stent graft600is a bifurcated stent graft that comprises one or more internal branches220.

In this example, branched bifurcated stent graft600includes a main body610, a first limb (or leg)612, and a second limb (or leg)614. Namely, first limb612and second limb614extend from the proximal end of main body610, wherein first limb612is longer than second limb614and second limb614is designed to receive a stent graft extension (not shown). Namely, a stent graft extension (e.g., proximal extension thoracic stent graft, not shown) is provided with branched bifurcated stent graft600for connecting to second limb614.

Main body610, first limb612, and second limb614are flexible tubular-shaped members, each of which is a tubular metal web covered by a woven polyester sleeve. Accordingly, branched bifurcated stent graft600is a covered stent. Main body610has a distal end616. First limb612has a proximal end618. Second limb614has a proximal end620.

Branched bifurcated stent graft600comprises at least one internal branch220inside main body610, wherein internal branch220is the internal branch described with reference to branched main body stent graft200shown inFIG.2throughFIG.5. In the example shown inFIG.6, branched bifurcated stent graft600comprises one internal branch220. However, this is exemplary only. Branched bifurcated stent graft600can comprise any number of internal branches220.

The use of branched AUI stent graft200and/or branched bifurcated stent graft600can be briefly summarized as follows. First, branched AUI stent graft200and/or branched bifurcated stent graft600is deployed from the groin into, for example, the proximal descending thoracic aorta. Then, the one or more internal branches220are used to deploy smaller renal stent grafts (not shown) from the groin into the arch branches of the thoracic aorta (seeFIG.12). For example, using an internal branch220, the renal artery can be cannulated first with a guide wire, then a small stent graft sheath, and then a small renal stent graft.

A stent graft delivery system for deploying the presently disclosed branched abdominal stent grafts, such as branched AUI stent graft200and branched bifurcated stent graft600, is described herein below with reference toFIG.7andFIG.8.

FIG.7shows a side view of an example of the presently disclosed stent graft delivery system700for deploying the presently disclosed branched abdominal stent grafts, such as branched AUI stent graft200and branched bifurcated stent graft600, for the endovascular repair of abdominal and/or thoracic aortic aneurysms.

Stent graft delivery system700comprises a primary stent graft sheath710. Primary stent graft sheath710is the directional mechanism of stent graft delivery system700.

A guide wire712runs through primary stent graft sheath710. A top cap714is at the distal end of guide wire712. Top cap714is, for example, a bullet-shaped plastic cap. Primary stent graft sheath710is the directional sheath and largest sheath of stent graft delivery system700. Primary stent graft sheath710can be, for example, an 18 to 20 French stent graft sheath. In one example, primary stent graft sheath710is constructed of nitinol-reinforced hydrophilic pliable plastic measuring about 50 cm long and delivered over any commercially available 0.035″ wire, which is guide wire712.

Primary stent graft sheath710encompasses a center shaft716through which other smaller sheaths may be introduced (e.g., stent graft sheaths720). Center shaft716is a length of hollow flexible tubing, such as plastic or silicone tubing. In one example, the diameter of center shaft716is about 9.0 millimeters. One or more openings718are provided in the sides of center shaft716and near the distal end thereof.

Branched AUI stent graft200or branched bifurcated stent graft600is provided in relation to primary stent graft sheath710and center shaft716. For example,FIG.7shows primary stent graft sheath710running through center shaft716and then through first limb612and main body610of branched bifurcated stent graft600. In this example, branched bifurcated stent graft600comprises two internal branches220. Primary stent graft sheath710may be sutured to the inner wall of branched bifurcated stent graft600.

In this example, because branched bifurcated stent graft600comprises two internal branches220, stent graft delivery system700further comprises two secondary stent graft sheaths720(e.g., secondary stent graft sheaths720a,720b). Each of the secondary stent graft sheaths720is used for visceral artery covered stent delivery. Secondary stent graft sheaths720are small sheaths compared to primary stent graft sheath710. Secondary stent graft sheaths720can be, for example, 7 French stent graft sheaths constructed of hydrophiliac pliable plastic and measuring about 50 cm in length and reinforced with a nitinol skeleton.

Each of the secondary stent graft sheaths720has a guide wire722running therethrough. For example, a guide wire722afor secondary stent graft sheath720aand a guide wire722bfor secondary stent graft sheath720b. The diameter of guide wire722can be, for example, about 0.035 inches or about 0.018 inches. Further, each of the secondary stent graft sheaths720may contain a 5 to 8 French compliant balloon dilator tip for the delivery of renal artery covered stents. In one example, the balloon dilator tip comprises a pre-formed 5-8 mm balloon (not shown) that is about 3-4 cm long, wherein the balloon may be guided into the aortic arch branch. The balloon may add stability to the system when delivering the renal stent grafts. This dilator may be advanced distal to the sheath itself to enable the inflated balloon located within a visceral artery to act as an anchor for the advancement of the sheath within the arterial ostium. The balloon can then be deflated and removed over the wire, leaving the sheath in its desired location. This component promotes trackability of the sheath into a visceral vessel in difficult anatomic scenarios as well as reduces the number of catheter/sheath exchanges, contributing to the efficiency of the overall operation.

Further, each of the secondary stent graft sheaths720has a standard hemostatic valve724at the proximal end thereof. For example, a hemostatic valve724afor secondary stent graft sheath720aand a hemostatic valve724bfor secondary stent graft sheath720b.

In this example, secondary stent graft sheath720aand guide wire722aenter the proximal end of center shaft716. Secondary stent graft sheath720aand guide wire722arun through center shaft716and then exit the side of center shaft716via one of the openings718. Then, secondary stent graft sheath720aand guide wire722aenter the proximal end of second limb614of branched bifurcated stent graft600. Secondary stent graft sheath720aand guide wire722arun through second limb614of branched bifurcated stent graft600and then enter proximal end224of the first internal branch220. Then, secondary stent graft sheath720aand guide wire722aexit the distal end222of the first internal branch220and exit the side of branched bifurcated stent graft600via its corresponding fenestration or opening230.

In like manner, secondary stent graft sheath720band guide wire722benter the proximal end of center shaft716. Secondary stent graft sheath720band guide wire722brun through center shaft716and then exit the side of center shaft716via one of the openings718. Secondary stent graft sheath720band guide wire722bthen enter the proximal end of first limb612of branched bifurcated stent graft600. Secondary stent graft sheath720band guide wire722brun through first limb612of branched bifurcated stent graft600and then enter proximal end224of the second internal branch220. Then, secondary stent graft sheath720band guide wire722bexit the distal end222of the second internal branch220and exit the side of branched bifurcated stent graft600via its corresponding fenestration or opening230.

Referring now toFIG.8shows a side view of stent graft delivery system700shown inFIG.7that further comprises a steering mechanism. For example, the steering mechanism comprises a handle730and two strings732. One end of the pair of strings732is coupled to handle730. The pair of strings732are integrated into primary stent graft sheath710. The opposite end of the pair of strings732is coupled to the distal end of primary stent graft sheath710. Namely, about 5 cm centimeters from the distal end of the inner shaft of primary stent graft sheath710, two 0.018″ strings (e.g., two strings732) attach at the three and nine o'clock positions and travel along the inner shaft through the outer sheath and attach at the same positions to a two inch-long handle730. According to one non-limiting aspect of the present disclosure, for example, with clockwise revolution of the hand, the stent graft and distal inner shaft of stent graft delivery system700tilts to the left; with counter-clockwise revolution, the stent graft and distal inner shaft of stent graft delivery system700tilt to the right.

Further, a pull control734may be provided on center shaft716to unwrap branched bifurcated stent graft600.

In one embodiment, a silicone ring (not shown) may be provided just below pull control734and proximal to handle730. Catheters and sheaths may be introduced through this ring wherein the silicone keeps the sheaths hemostatic as it seals around them. Sheaths and catheters that pass through the silicone ring enter the main common channel of the stent graft delivery system700.

According to an aspect of the present disclosure, the operation of stent graft delivery system700can be briefly summarized as follows. First, primary stent graft sheath710is used to deploy the presently disclosed branched abdominal stent grafts, such as branched main body stent graft200(FIG.2) and/or branched bifurcated stent graft600, into and from the groin, then into, for example, the proximal descending thoracic aorta or juxtarenal abdominal aorta. Then, the secondary stent graft sheaths720are used to deploy smaller renal stent grafts (not shown) to and through the one or more internal branches220and then into the arch branches of the thoracic aorta (seeFIG.12). For example, using an internal branch220, the renal artery can be cannulated first with guide wire722, then the small secondary stent graft sheath720, and then the small renal stent graft (not shown). The flared distal end222of the internal branches220assists in the selectivity of the aortic arch branches. For example, the flared distal end222of the internal branches220provides greater freedom to select renal arteries of a variety of anatomic configurations as compared with conventional stent graft delivery systems.

According to an aspect of the present disclosure, stent graft delivery system700is provided as a kit packaged with branched main body stent graft200or branched bifurcated stent graft600and with the one or more internal branches220of branched main body stent graft200or branched bifurcated stent graft600prewired with secondary stent graft sheaths720. For example,FIG.9shows a side view of an example of branched AUI stent graft200that comprises three internal branches220, which are prewired with three respective guide wires722.FIG.9also shows that the side of branched main body stent graft200that has the three internal branches220may be contoured (e.g., contoured portion226). Contoured portion226is provided to assist with packing the branched main body stent graft200and to assist arch vessel selection using catheter manipulation. Further,FIG.9shows that branched main body stent graft200may include a barb228on the side of main body210at each internal branch220. Barbs228can be flaps of fabric that help form a seal between the small renal stent grafts and branched main body stent graft200. In similar fashion, branched bifurcated stent graft600may include a contoured portion and barbs.

The use of “branches” is not limited to abdominal stent grafts (e.g., bifurcated stent grafts and AUI stent grafts), rather the use of “branches” can be also extended to thoracic components, such as thoracic stent graphs. More details of examples of thoracic stent graphs that include branches are described hereinbelow with reference toFIG.10andFIG.11.

FIG.10shows perspective views of a branched thoracic stent graft900and an example of an internal branch930that substantially conforms to the profile of the main body thereof. For example, branched thoracic stent graft900includes a main body910(e.g., a tubular body) that has a proximal end912and a distal end914. In this example, internal branch930runs in the same direction as main body910and is maintained in a substantially fixed position just under the surface of main body910. Internal branch930has a proximal end932and a distal end934. Proximal end932is accessible from inside main body910, while distal end934is configured to emerge from main body910within a contoured portion916thereof. When in use, a smaller stent graft (or bridging stent graft)940can be deployed from internal branch930.

In one example, internal branch930has a diameter of from about 8 mm to about 10 mm. Accordingly, the depth of contoured portion916can also be from about 8 mm to about 10 mm in diameter. Further, the portion at proximal end912of main body910that is outside contoured portion916can be a proximal seal zone918. In one example, proximal seal zone918is about 30 mm long. The portion at distal end914of main body910that is outside contoured portion916can be a distal seal zone920. In one example, distal seal zone920is about 20 mm long. However, the seal zones can generally range from about 15 cm to about 30 cm.

FIG.11shows a side view, top view, and end view of an example of branched thoracic stent graft900that comprises multiple internal branches930a,930b,930cand showing the relation of the internal branches930a,930b,930cone to another. In this example, branched thoracic stent graft900includes three internal branches930a,930b,930c. Branched thoracic stent graft900can be prewired and deployed using, for example, stent graft delivery system700(seeFIG.7andFIG.8).

The end view (proximal end) of branched thoracic stent graft900shows the predetermined spacing/positions of internal branches930a,930b,930caround the circumference of main body910, while the side and top views are intended to show an exemplary staggered relation of the internal branches930a,930b,930c. For example, in the end view, if internal branch930bis at 12 o'clock, then internal branch930cis at about 10 o'clock, and internal branch930ais at about 2 o'clock.

According to one aspect, as shown, the distal ends of internal branches930a,930b,930call emerge from contoured portion916of main body910. In this example, internal branch930ais a certain length, internal branch930bis a slightly shorter length than internal branch930a, and internal branch930cis a slightly shorter length than internal branch930c. In one example, the overall length of main body910of branched thoracic stent graft900can be from about 12 cm to about 20 cm.

As shown inFIG.11, branched thoracic stent graft900is a partially constrained main body thoracic stent graft with internal branches930a,930b,930cthat are arranged in a predetermined staggered fashion within this constrained portion (e.g., within contoured portion916). This enables a lower profile device with less graft material required to be packaged, thereby increasing the ability of the surgeon to deliver the stent graft with fewer access site complications. Positioning internal branches930a,930b,930cwithin the constrained portion (e.g., within contoured portion916) of main body910, enables more room within the blood vessel to cannulate or select the main branches that come off the aorta that are being preserved with the bridging stent grafts (e.g., bridging stent grafts940).

FIG.12is a side view showing a process of using branched main body stent graft200ofFIG.2, wherein three bridging stent grafts940are fully deployed to predetermined locations into the three thoracic aortic branches1010of the proximal descending thoracic aorta1200by use of branched main body stent graft200. InFIG.12, whereas the larger primary stent graft sheath710is used to deploy branched main body stent graft200, the smaller secondary stent graft sheaths720are used to deploy the bridging stent grafts940through the internal branches220.

FIG.13is a flow diagram of an example of a method of using the presently disclosed stent graft delivery system700to deploy the presently disclosed branched stent grafts, according to a minimum configuration of the disclosure. Method1300may include, but is not limited to, the following steps.

At a step1310, stent graft delivery system700that includes a certain type of branched abdominal stent graft is provided. In one example, stent graft delivery system700is packaged with a branched main body stent graft200and provided to the surgeon. In another example, stent graft delivery system700is packaged with a branched bifurcated stent graft600and provided to the surgeon. In another example, stent graft delivery system700is packaged with a branched thoracic stent graft900and provided to the surgeon.

At a step1312, primary stent graft sheath710of stent graft delivery system700is used to deploy the presently disclosed branched abdominal stent graft, such as branched main body stent graft200, branched bifurcated stent graft600, or branched thoracic stent graft900from the groin into, for example, the proximal descending thoracic aorta or juxtarenal abdominal aorta, respectively.

At a step1314, the secondary stent graft sheaths720are used to deploy smaller renal stent grafts to and through the one or more internal branches220and then into the arch branches of the thoracic aorta (seeFIG.12). For example, using an internal branch220, the renal artery can be cannulated first with guide wire722, then the small secondary stent graft sheath720, and then the small renal stent graft (not shown). The flared distal end222of the internal branches220assists in the selectivity of the aortic arch branches. Further, in the case of branched bifurcated stent graft600, the stent graft extension (e.g., proximal extension thoracic stent graft, not shown) is deployed and connected to second limb614.

FIG.14is a flow diagram of an example of a method1400of using the presently disclosed stent graft delivery system700for deploying the presently disclosed branched stent grafts for the endovascular repair of abdominal and/or thoracic aortic aneurysms. By way of example, branched bifurcated stent graft600ofFIG.6is deployed using method1400. Method1400may include, but is not limited to, the following steps.

At a step1410, using primary stent graft sheath710of stent graft delivery system700, the surgeon introduces branched bifurcated stent graft600via the common femoral artery access, either percutaneously or via open arterial exposure.

At a step1412, branched bifurcated stent graft600is positioned accurately to a predetermined location using the direction-bearing handle730, based upon the tortuosity of the native aorta at the level of the superior mesenteric artery and one or both renal arteries, which is determined either by preoperative mapping based upon computed tomographic angiography imaging and/or aortography. Handle730translates movement from the surgeon into precise and predetermined movements of primary stent graft sheath710at the level of the branched abdominal stent graft (e.g., branched bifurcated stent graft600).

At a step1414, main body610of branched bifurcated stent graft600is unsheathed, partially deploying branched bifurcated stent graft600and exposing the retrograde-facing internal branches220that will be used to assist with preservation of renal artery perfusion.

At a step1416, over the exemplary 0.018″ guide wire722that, according to one aspect of the disclosure are prepackaged with stent graft delivery system700and exiting though center shaft716located proximal to the directional handle730, the surgeon advances the one or more secondary stent graft sheaths720having a balloon dilator up through center shaft716into the one or more corresponding internal branches220. The flared ends of internal branches220provides the surgeon enough working room to cannulate each renal artery, either with the prepackaged wire722and balloon tip dilator or a commercially available catheter followed by the secondary stent graft sheath720.

At a step1418, once the surgeon tracks the balloon-tipped dilator into the renal artery and inflates the compliant balloon, the secondary stent graft sheath720may be tracked into the proximal ostium of the artery in preparation for delivery of the visceral covered stents (e.g., bridging stent grafts940shown inFIG.12). For example, balloon-expandable covered stent grafts (e.g., bridging stent grafts940shown inFIG.12) are deployed, which bridge the native renal artery with the internal branch, thereby creating a seal that excludes blood flow from the aneurysm sac but also promotes continued visceral perfusion.

At a step1420, main body610of branched bifurcated stent graft600is completely detached from primary stent graft sheath710of stent graft delivery system700via the removal of a constraining wire that is located along the posterior spine of branched main body stent graft200or branched bifurcated stent graft600. This is accomplished by the removal of a plug (not shown) that is attached to this constraining wire that is located just proximal to center shaft716.

At a step1422, the completion of the aortic repair consists of cannulation of the contralateral gate and deployment of an iliac limb stent graft (e.g., stent graft extension or proximal extension thoracic stent graft) consistent with currently marketed stent graft devices. The common femoral arteriotomy is then closed as per currently accepted methods.

FIG.15is a perspective view of an example of a branched bifurcated stent graft1500that comprises one or more external branches. In this example, branched bifurcated stent graft1500includes a main body1510, a first limb (or leg)1512, and a second limb (or leg)1514. Namely, first limb1512and second limb1514extend from the proximal end of main body1510, wherein first limb1512is longer than second limb1514and second limb1514is designed to receive a stent graft extension (not shown).

Main body1510, first limb1512, and second limb1514are flexible tubular-shaped members, each of which is a tubular metal web covered by a woven polyester sleeve. Accordingly, branched bifurcated stent graft1500is a covered stent. Main body1510has a distal end1516. First limb1512has a proximal end1518. Second limb1514has a proximal end1520.

Branched bifurcated stent graft1500comprises at least one external branch1530that protrudes from the side of main body1510. In the example shown inFIG.15, branched bifurcated stent graft1500comprises three external branches1530. However, this is exemplary only. Branched bifurcated stent graft1500can comprise any number of external branches1530. In one example, each of the external branches1530is about 2 cm long and is about 7 mm in diameter.

FIG.16shows branched bifurcated stent graft1500ofFIG.15when deployed in, for example, the juxtarenal abdominal aorta1600and shown in relation to the renal arteries. Branched bifurcated stent graft1500can be prewired and deployed using, for example, stent graft delivery system700. In this example, the one or more external branches1530are used to deploy smaller renal stent grafts (or bridging stent grafts)940into, for example, the renal arteries of the abdominal aorta.

In branched bifurcated stent graft1500, by having the external branches1530protrude from the sides of main body1510upon deployment, the flow dynamics may be improved within main body1510of branched bifurcated stent graft1500. Additionally, the branched bifurcated stent graft1500with the external branches1530may serve to decrease type II endoleaks (i.e., back bleeding from spinal arteries that feed the aneurysm sac). Further, the use of external branches1530is not limited to bifurcated stent grafts only, rather external branches1530can also be used with main body stent grafts.

Following long-standing patent law convention, the terms “a,” “an,” and “the” refer to “one or more” when used in this application, including the claims. Thus, for example, reference to “a subject” includes a plurality of subjects, unless the context clearly is to the contrary (e.g., a plurality of subjects), and so forth.

Throughout this specification and the claims, the terms “comprise,” “comprises,” and “comprising” are used in a non-exclusive sense, except where the context requires otherwise. Likewise, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items.

For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing amounts, sizes, dimensions, proportions, shapes, formulations, parameters, percentages, parameters, quantities, characteristics, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about” even though the term “about” may not expressly appear with the value, amount or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are not and need not be exact, but may be approximate and/or larger or smaller as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art depending on the desired properties sought to be obtained by the presently disclosed subject matter. For example, the term “about,” when referring to a value can be meant to encompass variations of, in some embodiments, ±100% in some embodiments ±50%, in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, in some embodiments ±1%, in some embodiments ±0.5%, and in some embodiments ±0.1% from the specified amount, as such variations are appropriate to perform the disclosed methods or employ the disclosed compositions.

Further, the term “about” when used in connection with one or more numbers or numerical ranges, should be understood to refer to all such numbers, including all numbers in a range and modifies that range by extending the boundaries above and below the numerical values set forth. The recitation of numerical ranges by endpoints includes all numbers, e.g., whole integers, including fractions thereof, subsumed within that range (for example, the recitation of 1 to 5 includes 1, 2, 3, 4, and 5, as well as fractions thereof, e.g., 1.5, 2.25, 3.75, 4.1, and the like) and any range within that range.

Although the foregoing subject matter has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be understood by those skilled in the art that certain changes and modifications can be practiced within the scope of the disclosed subject matter.