Stent graft systems with restraints in channels and methods thereof

Abstract

To provide for enhancement in compression and expansion of stent grafts for ease of insertion into the vessels of a patient.SOLUTION: A stent graft system 1 includes a first layer 2a of a graft material, a second layer 2b of a graft material, one or more stent members 5a, one or more diameter reducing belts 6a, and a release wire 12. The stent members are located between the first layer of the graft material and the second layer of the graft material. The second layer of the graft material is formed to have a corresponding channel 3a over each of the stent members. The one or more diameter reducing belts each includes a loop 7a at both ends and each is located in a corresponding channel around a corresponding one of the stent members. The release wire passes through both loops of each of the reducing belts when the stent members are in a compressed state. Pulling the release wire allows for the stent graft system to radially expand.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED PATENT APPLICATIONS] This application claims priority from U.S. Provisional Patent Application No. 62 / 678,961, filed May 31, 2018, the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE DISCLOSURE The embodiments disclosed herein relate generally to the field of endovascular stent graft systems. In particular, various embodiments relate to systems including stent grafts, methods of making such stent grafts, and methods of using such stent grafts to treat aneurysms. [Background technology]

[0003] An aneurysm is a condition characterized by the dilation and weakening of the walls of an individual's arteries. Aneurysms can develop at different locations within an artery. For example, a thoracic aortic aneurysm or an abdominal aortic aneurysm may develop within an individual's body. Such conditions can be serious and life-threatening to the individual, thus requiring medical intervention to treat the condition. Existing systems and methods for treating such conditions include invasive surgical procedures with graft replacement of the affected blood vessel or body lumen.

[0004] Surgical procedures to treat aneurysms have a relatively high morbidity and mortality rate due to risk factors inherent in surgical repair of the artery or arterial wall. Long and painful recoveries are often required, resulting in significant medical costs. Because of these inherent risks and the complexity of surgical repair of aortic aneurysms, endovascular repair has become a widely used alternative therapy.

[0005] In endovascular repair, an expandable stent graft is placed within the damaged artery to reinforce the weakened section of the arterial wall. A stent graft is a woven tube supported by a scaffold or metal wire stent. A stent graft has several layers of material, such as polytetrafluoroethylene (PTFE), that surrounds the scaffold. To perform an endovascular repair of an aneurysm, a surgeon makes a small incision, typically in the patient's groin, and inserts a compressed stent graft delivery system through the incision into the blood vessel to the location of the aneurysm. The stent graft is then expanded within the artery to reinforce the damaged arterial wall. Summary of the Invention [Means for solving the problem]

[0006] Various embodiments provide improved compression and expansion of the stent graft for ease of insertion into one or more blood vessels of a patient. Various embodiments provide for endovascular stent graft compression by providing multiple layers of graft material surrounding the stent members, creating channels around each of the stent members using the graft material, disposing a reduced diameter belt across the stent members in the channels between the graft material layers, and providing release wires through end loops of the reduced diameter belt for easily releasing the reduced diameter belt to allow the stent graft to expand as needed.

[0007] In some embodiments, the stent graft system includes a stent graft, one or more reducing belts, such as sutures or wires, and a release or lock wire. In various embodiments, the graft material for the stent graft is formed with an integrated channel surrounding each of the one or more stent members. In some embodiments, the one or more reducing belts are made of threads or wires, each routed through a corresponding channel defined by the shape of the graft material around the corresponding stent member. In various embodiments, each reducing belt has a length less than the circumference of the corresponding stent member fully expanded, but greater than the circumference of the stent member when in a compressed state, thus allowing the stent member to be held in a compressed state. In some embodiments, each reducing belt has loops on both ends, and the release wire is configured to pass through both loops of the reducing belt when the stent graft is in a compressed state. The release wire is then pulled from the loops of the reducing belt, allowing the stent graft to radially expand.

[0008] A stent graft system according to an embodiment includes a first layer of graft material, a second layer of graft material, a stent member, and a reduced diameter belt. The stent member is positioned between the first layer of graft material and the second layer of graft material. The reduced diameter belt is at least partially positioned in a channel between the second layer of graft material and the first layer of graft material and around at least a portion of the stent member.

[0009] In various embodiments, the second layer of graft material has a shape that provides a channel between the second layer of graft material and the first layer of graft material. In various embodiments, the reduced diameter belt has a length that is less than the circumference of the stent member when the stent member is fully expanded and greater than the circumference of the stent member when the stent member is in a compressed state. In some embodiments, the reduced diameter belt includes a plurality of loops, with a corresponding one of the plurality of loops at each end of the reduced diameter belt. Also, in some embodiments, the stent graft system further includes a release wire passing through the loop of the reduced diameter belt.

[0010] In various embodiments, the stent member is radially expandable from the compressed state to the restored state and the reduced diameter belt is releasable to allow the stent member to expand from the compressed state to the restored state. In some embodiments, the stent graft system further includes a second stent member positioned between the first layer of graft material and the second layer of graft material, and a second reduced diameter belt positioned at least partially in the second channel between the second layer of graft material and the first layer of graft material and around at least a portion of the second stent member.

[0011] In some embodiments, the second layer of graft material has a shape that provides a second channel between the second layer of graft material and the first layer of graft material. Also, in some embodiments, the reducing belt includes a loop and the second reducing belt also includes a loop, and the stent graft system further includes a release wire passing through the loop of the reducing belt and passing through the loop of the second reducing belt. In some embodiments, the stent graft system further includes a pleat in the second layer of graft material between the stent member and the second stent member.

[0012] A method according to embodiments of manufacturing a stent graft system includes placing a plurality of stent members on a first layer of graft material, placing a respective spacer of the plurality of spacers at least partially around each stent member of the plurality of stent members, encapsulating at least a portion of each spacer of the plurality of spacers with a second layer of graft material, and removing each of the plurality of spacers from a respective opening in the second layer of graft material to leave a respective channel around each stent member of the plurality of stent members between the second layer of graft material and the first layer of graft material. In various embodiments, each spacer of the plurality of spacers comprises a tube.

[0013] In various embodiments, the method further includes placing a respective one of the plurality of reducing belts around each stent member of the plurality of stent members at least partially within the respective channel. In some embodiments, each one of the plurality of reducing belts includes a thread. In some embodiments, each of the plurality of reducing belts includes a loop, and the method further includes placing a release wire through the loop of each one of the plurality of reducing belts to hold the plurality of stent members in radial compression. In some embodiments, the reducing belts are positioned such that an end of each one of the reducing belts extends from a respective opening in the second layer of graft material.

[0014] In various embodiments, the method further includes axially compressing the second layer of graft material to form pleats in the second layer of graft material, applying heat to set the folds for the pleats in the second layer of graft material, and tensioning the second layer of graft material to axially restore the second layer of graft material after the pleats are thermally set. In some embodiments, the applying heat includes baking the second layer of graft material in an oven to set the folds for the pleats in the second layer of graft material.

[0015] A method according to an embodiment allows for the use of a stent graft system, the stent graft system including a first layer of graft material, a second layer of graft material, a plurality of stent members, and a plurality of reduced diameter belts. The method includes positioning the stent graft system in a vessel with each stent member of the plurality of stent members held in a compressed state by a corresponding reduced diameter belt of the plurality of reduced diameter belts positioned at least partially in a corresponding channel between the second layer of graft material and the first layer of graft material, and releasing the plurality of reduced diameter belts to allow the plurality of stent members to expand from the compressed state to a restored state. In some embodiments, releasing the plurality of reduced diameter belts includes pulling a release wire through and from one or more loops of the plurality of reduced diameter belts. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 illustrates a stent graft system according to an embodiment. [Diagram 2] 1 is a cross-sectional view of a stent graft system according to an embodiment. [Diagram 3] 1 is a cross-sectional view of a stent graft system according to an embodiment. [Figure 4] 1 is a flow diagram of a method of manufacturing a stent graft system according to an embodiment. [Diagram 5] 1A-1D illustrate a stent graft system during stages of manufacture according to an embodiment. [Figure 6] 1A-1C show a stent graft system during different stages of manufacture according to an embodiment. [Figure 7] 13A-13C show a stent graft system during yet another stage of manufacture according to an embodiment. [Figure 8] FIG. 1 shows a stent graft system according to an embodiment inserted into a blood vessel and in a compressed state. [Figure 9] FIG. 2 shows a stent graft system according to an embodiment inserted into a blood vessel and in a restored state. [Figure 10] 1 is a flow diagram of a method of deploying a stent graft system in a vessel according to an embodiment. [Figure 11] FIG. 1 shows an embodiment of a stent graft system having an anchoring stent for insertion into a vessel for fixation. [Figure 12] 1 is a flow diagram of a method of manufacturing a stent graft system according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In these drawings, like symbols typically identify like items unless the context dictates otherwise. The exemplary embodiments described in the detailed description, the drawings, and the claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are expressly contemplated and form a part of the present disclosure.

[0018] Various embodiments allow for improved methods of compression and expansion of the stent graft by providing a suture or wire-like reduced diameter belt circumferentially around the stent member within a channel formed by the graft material. Various embodiments allow for improved compression and expansion of the stent graft by (1) providing multiple layers of graft material surrounding the stent member, (2) disposing a circumferential reduced diameter belt over the stent member between the graft material layers, and (3) providing release wires through the ends of the reduced diameter belt to easily release the reduced diameter belt to allow radial expansion of the stent member as needed.

[0019] Various embodiments provide for a stent graft system having circumferential reducing belts surrounding the stent members. In various embodiments, each of the reducing belts has a length less than the circumference of the corresponding stent member when the stent member is in a fully expanded state and a length greater than the circumference of the corresponding stent member when the stent member is in a compressed state. The reducing belts surround the stent members when the stent members are in a compressed state. In various embodiments, each of the reducing belts has loops on both of its ends. A release wire passes through both loops of each reducing belt surrounding each stent member to maintain the compression of the stent members. In various embodiments, after insertion of the stent graft system into the vessel, the release wire is removed from the loops of the reducing belts to allow expansion of the stent members.

[0020] 1 shows a stent graft system 1 according to an embodiment. The stent graft system 1 includes a first layer of graft material 2a, a second layer of graft material 2b, stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n, and a release wire 12. The stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are positioned between the first layer of graft material 2a and the second layer of graft material 2b. The second layer of graft material 2b is formed to have a shape that provides corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n. In various embodiments, the corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are circumferential channels.

[0021] Each of the reducing belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n includes a first loop 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n corresponding to one end and a second loop 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n corresponding to the other end. Each of the reducing belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is positioned in a corresponding channel 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around a corresponding one of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n.

[0022] Each first loop 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and second loop 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n of the reduced belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n extends from a corresponding opening 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second layer of graft material 2b. The release wire 12 passes through first loops 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and second loops 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n of each of the reducing belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n when the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are in a compressed state.

[0023] In various embodiments, each of the reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is configured to extend from the corresponding stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n when the corresponding stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n is fully expanded. 5, the length of the reducing belt 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is shorter than the circumference of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n when the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are in a compressed state, allowing the reducing belt 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n to maintain the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n in a compressed state until the release wire 12 is pulled. With the release wire 12 tensioned, the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n expand to an expanded or restored state.

[0024] The stent graft system 1 is a hollow tubular device having a first layer 2a of graft material forming a tubular wall and defining an open lumen. Although the stent graft system 1 seen in FIG. 1 is shown as being substantially tubular, one skilled in the art will appreciate that the stent graft system 1 may be of any shape suitable for delivery and placement at a target site in a patient. In various embodiments, the first and second layers 2a, 2b of graft material comprise graft material made from one or more polymers or other suitable materials. In some embodiments, the first and second layers 2a, 2b of graft material are made of polytetrafluoroethylene (PTFE). In some embodiments, the first and second layers 2a, 2b of graft material are made of expanded polytetrafluoroethylene (ePTFE).

[0025] In some embodiments, the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are connected together as a single stent, but in some embodiments are separate from one another. Each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n can be made from any other suitable material, including, but not limited to, stainless steel, nickel-titanium alloys (NiTi) such as Nitinol, or cobalt-based alloys such as Elgiloy, platinum, gold, titanium, tantalum, niobium, and / or combinations thereof. In the illustrated embodiment, each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n is radially expandable from a compressed state to an expanded or restored state. The stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n may be balloon expandable or self-expandable. Although the embodiment shown in FIG. 1 shows a certain number of stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, it should be appreciated that any number of stent members may be used in various embodiments. In the illustrated embodiment, each portion of the stent graft system 1 flares outwardly at both the proximal and distal ends, although in various other embodiments the stent graft system may be uniform throughout its length.

[0026] Each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n is compressed by a corresponding reduction belt 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n to circumferentially reduce the diameter of the stent member and hold the stent members in a compressed state. In various embodiments, the reduction belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n are sutures, threads, wires, or the like.

[0027] The reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n surround corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n and are each positioned within corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n between the first layer of graft material 2a and the second layer of graft material 2b. Each end of the reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n has a corresponding first loop 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and second loop 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n extending from a corresponding opening 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second layer of graft material 2b. The release wire 12 passes through the first loops 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and the second loops 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n of each of the reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n and extends outward at both the proximal and distal ends of the stent graft system 1. With the release wire 12 pulled, each of the reducing belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n releases compression on the corresponding stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n allowing the stent graft system 1 to expand radially.

[0028] FIG. 2 shows a cross-section of the stent graft system 1 of FIG. 1 according to an embodiment. A stent member 5a is positioned between a first layer of graft material 2a and a second layer of graft material 2b. The second layer of graft material 2b is formed to provide a corresponding channel 3a around the stent member 5a. A reducing belt 6a has a first loop 7a at a first end and a second loop 8a at a second end and extends from an opening 4a in the second layer of graft material 2b. The reducing belt 6a is positioned in the channel 3a around the stent member 5a. A release wire 12 (see FIG. 1) can be passed through the first loop 7a and the second loop 8a of the reducing belt 6a to allow the reducing belt 6a to hold the stent member 5a in a compressed state.

[0029] Figure 3 is similar to Figure 2, with like reference labeling indicating like elements, but shows a cross section of a stent graft system further including an additional third layer of graft material 2c between the stent member 5a and the second layer of graft material 2b. Of course, in various other embodiments, any number of layers of graft material can be used. The channel 3a in the embodiment of Figure 3 is between the second layer of graft material 2b and the third layer of graft material 2c.

[0030] Figure 4 is a flow diagram of a method of manufacturing a stent graft system according to an embodiment. Figures 5 and 6 show a stent graft system 10 during various stages of manufacture according to an embodiment and being manufactured into the stent graft system 1 of Figure 1. Stages of manufacture according to various embodiments are also shown in Figure 7. With reference to Figures 1, 4, 5 and 6, in step 100, stent members are positioned on the first layer of graft material. For example, stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are placed on the first layer of graft material 2a. In step 110, a respective spacer is placed around each stent member. For example, a respective spacer 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n is disposed around each stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n. In various embodiments, each of the spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n comprises a tube or the like. In various embodiments, each of the spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n is a Kapton tube or the like. In various embodiments, each of the spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n comprises a polyimide or the like.

[0031] In step 120, the spacers are encapsulated using a second layer of graft material, with an end of each spacer protruding from a respective opening in the second layer of graft material. For example, spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n are encapsulated using second layer of graft material 2b, with an end of each of spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n protruding from a respective opening 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in second layer of graft material 2b.

[0032] In step 130, the stent graft system is axially compressed to form pleats in the layer of graft material between the stent members. For example, the stent graft system 10 is axially compressed in a telescopic manner to form pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m (see FIG. 6) between each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n in the second layer of graft material 2b. Referring to FIGS. 4 and 6, in step 140, heat is applied to the stent graft system to solidify the folds for the pleats in the layer of graft material. For example, heat may be applied to the stent graft system 10 while it is compressed telescopically to set the folds for pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, and 11m.

[0033] In various embodiments, the heat application step is performed by ironing the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m to set the creases for the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m. In some embodiments, the heat application step is performed by placing the stent graft system 10 in an oven and baking the stent graft system 10 for a predetermined time to heat set the creases for the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m. In various embodiments, the stent graft system 10 is longitudinally compressed to form a plurality of circumferential pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m having a predetermined orientation. Each of the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m may include a folded or turned-up surface of the graft material formed in an area between the locations of each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n. In various embodiments, each of the plurality of circumferential pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, and 11m is disposed between crowns formed by two respective stent members of stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, and 5n.

[0034] In step 150, the stent graft system is pulled to restore the graft material layer after the pleats have been thermally set. For example, the stent graft system 10 of FIG. 6 is pulled longitudinally to restore the stent graft system 10 to its longitudinal orientation after the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m have been thermally set. With reference to FIGS. 1, 4, 5, 6, and 7, in step 160, each of the spacers is removed from its respective opening in the second layer of graft material to leave a respective circumferential channel around each stent member. For example, as in the resulting stent graft system 1, each of the spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n of the stent graft system 10 is removed from its respective opening 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second layer of graft material 2b so as to leave a respective channel 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n.

[0035] 1, 4 and 7, in step 170, respective reduced diameter belts having end loops extending from respective openings in the second layer of graft material are placed in respective channels around each stent member. For example, each one of the reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n having an end loop extending from a respective opening 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second layer of graft material 2b is placed in a corresponding channel 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n. In step 180, a release wire is placed through the end loop of each of the reduced diameter belts to hold the stent members in radial compression. For example, the release wire 12 is positioned through corresponding first loops 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and corresponding second loops 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n of each of the reduced belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n to hold the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n in radial compression. Figure 7 shows an example of a manufacturing stage for inserting a release wire 12 for a stent graft system 1. In various embodiments, an open ended cylindrical device 30 is used to hold the stent graft system 1 when the release wire 12 is attached.

[0036] Figure 8 shows an example of the stent graft system 1 of Figure 1 in a compressed state deployed in a blood vessel, such as the aorta 20. Figure 9 shows an example of the stent graft system 1 in an expanded state after solidification into the aorta 20. Figure 10 is a flow diagram of a method according to an embodiment for deploying a stent graft system, such as the stent graft system 1 of Figure 1 in a blood vessel. The method shown in Figure 10 allows for the use of a stent graft system including a first layer of graft material, a second layer of graft material, a plurality of stent members, and a plurality of reduced diameter belts.

[0037] Referring to Figures 1, 8 and 10, in step 200, the stent graft system is positioned in the blood vessel with each stent member of the plurality of stent members held in compression by a corresponding one of a plurality of reducing belts positioned at least partially in a corresponding channel between the second layer of graft material and the first layer of graft material. For example, a stent graft system 1 having reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is positioned in the aorta 20, where the reduced diameter belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n are within corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n of the stent graft system 1 between a first layer of graft material 2a and a second layer of graft material 2b.

[0038] In various embodiments, the stent graft system 1 allows for controlled and precise deployment providing repositioning capabilities. The folds for pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m between corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n facilitate curving the stent graft system 1 within the aorta 20 as shown in FIG. 8 in various embodiments. The stent graft system 1 can be positioned to repair the aorta 20 over an aneurysm 21.

[0039] 1, 8, 9, and 10, in step 210, the plurality of reducing belts are released to allow the plurality of stent members to expand from a compressed state to a restored state, which is an expanded state. In some embodiments, releasing the plurality of reducing belts includes pulling a release wire 220 through and out of one or more loops of the plurality of reducing belts. For example, the release wire 12 is pulled to release the reducing belts 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n around the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, allowing the stent graft system 1 to radially expand within the aorta 20 from the compressed state shown in FIG. 8 to the restored state shown in FIG. 9. As shown in FIG. 9, the stent graft system 1 can expand radially to contact a vessel wall, such as the wall of the aorta 20, and cross an aneurysm, such as aneurysm 21 in the aorta 20.

[0040] 11 illustrates an embodiment of the stent graft system 1 further including a stent anchor 50 at the proximal end. The stent anchor 50 allows for anchoring of the stent graft system 1 within a blood vessel, such as the aorta 20. In various embodiments, the stent anchor 50 includes barbs 51 or other fixation elements that are radially expandable from a compressed state and allow the barbs 51 to penetrate a blood vessel wall, such as the wall of the aorta 20, when expanded to an expanded or restored state.

[0041] 1 and 2, a stent graft system 1 according to an embodiment includes a first layer of graft material 2a, a second layer of graft material 2b, a stent member 5a, and a reduced diameter belt 6a. The stent member 5a is positioned between the first layer of graft material 2a and the second layer of graft material 2b. The reduced diameter belt 6a is at least partially positioned in the channel 3a between the second layer of graft material 2b and the first layer of graft material 2a and around at least a portion of the stent member 5a.

[0042] The second layer of graft material 2b has a shape that provides a channel 3a between the second layer of graft material 2b and the first layer of graft material 2a. In various embodiments, the reduced diameter belt 6a of the stent graft system 1 of FIG. 1 has a length that is shorter than the circumference of the stent member 5a when the stent member 5a is fully expanded as in FIG. 9, but longer than the circumference of the stent member 5a when the stent member 5a is in a compressed state as in FIG. 8. With reference to FIGS. 1 and 2, in some embodiments, the reduced diameter belt 6a includes a first loop 7a and a second loop 7b at the ends of the reduced diameter belt 6a. Also, in some embodiments, the stent graft system 1 includes a release wire 12 that passes through the first loop 7a and the second loop 8a of the reduced diameter belt 6a.

[0043] The stent member 5a is radially expandable from a compressed state to a restored state, and the reducing belt 6a is releasable to allow the stent member 5a to expand from the compressed state to the restored state. The stent graft system 1 further includes a stent member 5b positioned between the first layer of graft material 2a and the second layer of graft material 2b, and a reducing belt 6b positioned at least partially in the channel 3b, between the second layer of graft material 2b and the first layer of graft material 2a and around at least a portion of the stent member 5b.

[0044] The second layer of graft material 2b has a shape that provides a channel 3b between the second layer of graft material 2b and the first layer of graft material 2a. Similarly, in some embodiments, the reducing belt 6b includes a first loop 7b and a second loop 8b, and the stent graft system 1 includes a release wire 12 that passes through the first loop 7a and the second loop 8a of the reducing belt 6a and through the first loop 7b and the second loop 8b of the reducing belt 6b. As shown in FIG. 9, in some embodiments, the stent graft system 1 further includes a fold due to a pleat 11a in the second layer of graft material 2b between the stent member 5a and the second stent member 5b.

[0045] 12 is a flow diagram of a method of manufacturing a stent graft system according to an embodiment. In step 300, a plurality of stent members are placed on a first layer of graft material. In step 310, a respective spacer of a plurality of spacers is placed at least partially around each stent member of the plurality of stent members. In step 320, at least a portion of each spacer of the plurality of spacers is encapsulated using a second layer of graft material.

[0046] In step 330, the second layer of graft material is axially compressed to form pleats in the second layer of graft material. In step 340, heat is applied to solidify the creases for the pleats in the second layer of graft material. In some embodiments, the applying of heat includes baking the second layer of graft material in an oven to solidify the creases for the pleats in the second layer of graft material. In step 350, the second layer of graft material is tensioned to axially restore the second layer of graft material after the pleats are thermally solidified. In step 360, each of the plurality of spacers is removed from a respective opening in the second layer of graft material to leave a respective channel around each of the plurality of stent members between the second layer of graft material and the first layer of graft material. In various embodiments, each of the plurality of spacers includes a tube.

[0047] At step 370, a respective one of the plurality of reducing belts is placed around each one of the plurality of stent members at least partially within the respective channel. In some embodiments, each one of the plurality of reducing belts comprises a yarn. In some embodiments, each one of the plurality of reducing belts comprises a natural or synthetic fiber. In some embodiments, each one of the plurality of reducing belts comprises a metal. In some embodiments, each one of the plurality of reducing belts comprises a loop. At step 380, a release wire is placed through the loop of each one of the plurality of reducing belts to hold the plurality of stent members in radial compression. In some embodiments, the reducing belt is positioned such that an end of each one of the plurality of reducing belts extends from a respective opening in the second layer of graft material.

[0048] In various embodiments, a release wire extends through the stent graft system to lock a reduced diameter belt, such as a suture, in place surrounding the stent member. The release wire is then removed from the suture loop to release the suture and allow expansion of the stent member. After expansion of the stent member, the stent graft system exerts a radially outward force against the aortic wall. In various embodiments, the stent graft system functions to reinforce weakened arterial walls that may have been caused by an aneurysm.

[0049] In various embodiments, during manufacture of the stent graft system, the first layer of graft material and the stent member are surrounded by a tube. The stent member, the first layer of graft material, and the tube are then encapsulated with an additional layer of graft material to provide a channel between the two layers of graft material, with the tube located within the channel. In various embodiments, the graft material layer is thermally crimped using heat. In various embodiments, the tube is removed from between the layers of graft material, thereby leaving a channel on each of the stent members. In some embodiments, sutures are placed in the corresponding channel around each stent member between the layers of graft material to replace the tube and maintain compression of the stent members. In various embodiments, release wires are inserted through the suture loops that extend from the distal end to the proximal end of the stent graft system to lock these sutures in place to maintain compression of the stent members. In various embodiments, pulling the release wire releases the sutures, allowing the stent members to expand. The release wire can be removed to correct its location within an artery, such as the aorta, after insertion of the stent graft system within a patient.

[0050] In various embodiments, the stent members can be attached or laminated to one or more layers of graft material. In various embodiments, the stent members are fully laminated or fused into one or more layers of graft material. In some embodiments, the stent members are partially laminated or free-floating in or between one or more layers of graft material. In some embodiments, the graft material layers extend the entire length of the stent graft system from the proximal end to the distal end. In some other embodiments, the graft material layers do not cover the entire length of the stent graft system, leaving portions of the distal and / or proximal ends exposed, thereby leaving some stent members exposed at both ends.

[0051] In various embodiments, there is a tube surrounding the stent members during manufacture. In various embodiments, each stent member has a separate tube circumferentially surrounding it. In some embodiments, multiple tubes can be connected at various points. In some embodiments, the tube can consist of a single section that is helically wrapped around some or all of the stent members. In various embodiments, the stent members are at least partially laminated between layers of graft material.

[0052] In various embodiments, during manufacture, longitudinal compression of the stent-graft system from a longitudinally extended configuration to a compressed configuration followed by thermal crimping creates a plurality of circumferential pleats in a predetermined orientation such that the pleated sections of the stent-graft system nest within one another along the axis. In various embodiments, any orientation of the circumferential pleats can be thermally crimped to lock the pleats in this orientation such that when the stent-graft is again longitudinally compressed or tilted in its natural state after implantation of the stent-graft system, the compressed stent-graft will remember and regain the pre-set pleat orientation.

[0053] In various embodiments, the release wire passes through loops on all of the sutures around all of the stent members, thereby compressing each stent member. In various other embodiments, the release wire can pass through the suture loops on only a portion of the stent members. Some embodiments can have multiple release wires, each for releasing the reduced diameter belts around a corresponding subset of the stent members. In various embodiments, the release wire functions as a locking mechanism that holds the suture in a tightly wrapped position circumferentially around the stent members until it is pulled. In various embodiments, when the release wire is removed from the suture, the suture loop is released and the suture no longer tightly wraps around the stent members, allowing the stent members to return to their radially expanded state.

[0054] In various embodiments, the stent graft system according to the embodiment is deployed in the aortic arc. In some embodiments, the stent graft system according to the embodiment is inserted into the descending aortic portion of the aorta. In various embodiments, the stent graft system has a stent member configured to allow it to bend to conform to the shape of the aorta. In various embodiments, upon expansion of the stent member, the stent graft system exerts a radially outward force against the aortic wall. In various embodiments, the stent graft system includes a branch portion for extending into one or more additional vessels.

[0055] Various embodiments provide improved compression and controlled expansion of the stent graft system upon deployment within a patient. A reduction belt circumferentially surrounds the stent member of the stent graft system. In some embodiments, a release wire is threaded through a loop of the reduction belt that extends from a channel opening in the graft material, with the release wire extending on both ends of the stent graft system. Removal of the release wire loosens the reduction belt allowing the stent member of the stent graft system to fully expand. The reduction belt and release wire allow for controlled and precise deployment of the stent graft system into one or more blood vessels.

[0056] A stent graft system according to embodiments includes a first layer of graft material, a second layer of graft material, one or more stent members, one or more reduced diameter belts, and a release wire. In various embodiments, the one or more stent members are positioned between the first layer of graft material and the second layer of graft material, and the second layer of graft material is formed to provide a corresponding channel around each of the one or more stent members. In various embodiments, each of the one or more reduced diameter belts has a loop at each end and is positioned in a corresponding channel around a corresponding one of the stent members, and has a length that is less than the circumference of the corresponding stent member when the corresponding stent member is fully expanded and greater than the circumference of the corresponding stent member when the stent member is in a compressed state. In various embodiments, the release wire passes through both loops of each of the one or more reduced diameter belts when the one or more stent members are in a compressed state.

[0057] The embodiments disclosed herein are illustrative in all respects and should not be considered as limiting the present invention. The present invention is in no way limited to the above-described embodiments. Various modifications and changes can be made to these embodiments without departing from the spirit and scope of the present invention. Various modifications and variations that fall within the meaning and range of equivalence of the claims are intended to be within the scope of the present invention. [Explanation of symbols]

[0058] 1. Stent graft system 2a First layer of graft material 5a, 5b Stent member 6a, 6b Reducing belt 12 Release wire

Claims

1. a first layer of graft material; a second layer of graft material; and a stent member positioned between the first layer of graft material and the second layer of graft material; a reduced diameter belt positioned at least partially in a channel between the second layer of graft material and the first layer of graft material and around at least a portion of the stent member; A stent graft system comprising:

2. the second layer of graft material has a shape that provides the channel between the second layer of graft material and the first layer of graft material. The stent graft system of claim 1 .

3. the reduced diameter belt has a length less than the circumference of the stent member when the stent member is fully expanded but greater than the circumference of the stent member when the stent member is in a compressed state. The stent graft system of claim 1 .

4. the tapered belt includes loops, with a corresponding one of the loops at each end of the tapered belt; The stent graft system of claim 1 .

5. a release wire passing through the loop of the reducing belt; The stent graft system of claim 4 further comprising:

6. the stent member being radially expandable from a compressed state to a restored state; the reduction belt is releasable to allow the stent member to expand from the compressed state to the restored state. The stent graft system of claim 1 .

7. a second stent member positioned between the first layer of graft material and the second layer of graft material; a second reduced diameter belt positioned at least partially in a second channel between the second layer of graft material and the first layer of graft material and about at least a portion of the second stent member; The stent graft system of claim 1 further comprising:

8. the second layer of graft material has a shape that provides the second channel between the second layer of graft material and the first layer of graft material.

8. The stent graft system of claim 7.

9. the tapered belt includes a loop, the second tapered belt also includes a loop, the stent graft system further comprising a release wire passing through the loop of the reducing belt and passing through the loop of the second reducing belt.

8. The stent graft system of claim 7.

10. a pleat in the second layer of graft material between the stent member and the second stent member; The stent graft system of claim 7 further comprising:

11. 1. A method of manufacturing a stent graft system, comprising: placing a plurality of stent members over the first layer of graft material; placing a respective spacer of a plurality of spacers at least partially around each stent member of the plurality of stent members; encapsulating at least a portion of each spacer of the plurality of spacers with a second layer of graft material; removing each of the plurality of spacers from a respective opening in the second layer of graft material to leave a respective channel around each stent member of the plurality of stent members between the second layer of graft material and the first layer of graft material; The method according to claim 1, further comprising:

12. each spacer of the plurality of spacers comprises a tube; 12. The method of claim 11 .

13. placing a respective one of a plurality of reducing belts in the respective channel at least partially around each stent member of the plurality of stent members; 12. The method of claim 11 further comprising:

14. each of the plurality of reducing belts includes a yarn; 14. The method of claim 13.

15. each of the plurality of reducing belts includes a loop; the method further comprising placing a release wire through the loops of each of the plurality of reduced diameter belts to hold the plurality of stent members in radial compression.

14. The method of claim 13.

16. the reducing belts are positioned such that an end of each reducing belt in the plurality of reducing belts extends from a respective opening in the second layer of graft material.

14. The method of claim 13.

17. axially compressing the second layer of graft material to form pleats in the second layer of graft material; applying heat to solidify the creases for the pleats in the second layer of graft material; pulling the second layer of graft material after the pleats are thermally set to axially restore the second layer of graft material; 12. The method of claim 11 further comprising:

18. the applying heat step includes baking the second layer of graft material in an oven to solidify the creases for the pleats in the second layer of graft material.

20. The method of claim 17 .

19. 1. A method of using a stent graft system comprising a first layer of graft material, a second layer of graft material, a plurality of stent members, and a plurality of reduced diameter belts, comprising: positioning the stent graft system in a vessel with each stent member of the plurality of stent members held in compression by a corresponding one of the plurality of reducing belts positioned at least partially in a corresponding channel between the second layer of graft material and the first layer of graft material; releasing the plurality of reduction belts to allow the plurality of stent members to expand from the compressed state to a restored state; The method according to claim 1, further comprising:

20. the step of releasing the plurality of reduced diameter belts includes pulling a release wire through and out of one or more loops of the plurality of reduced diameter belts.

20. The method of claim 19 .

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