Stent graft system with constraints in a channel and method thereof

Abstract

The stent graft system includes a first graft material layer, a second graft material layer, one or more stent members, one or more constriction bands, and a release wire. One or more stent members are located between the first graft material layer and the second graft material layer. The second graft material layer is formed to have corresponding channels in each of the one or more stent members. Each of the one or more constriction bands includes loops at both ends and is located in a corresponding channel around a corresponding one of the stent members. When the one or more stent members are in a compressed state, the release wire passes through two loops of each of the one or more constriction bands. Pulling the release wire allows the stent graft system to expand radially.

Description

[0001] Cross - reference to related patent applications

[0002] This application claims the benefit of U.S. Provisional Patent Application Serial No. 62 / 678,961, filed on May 31, 2018, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments described herein generally relate to the field of endovascular stent - graft systems. In particular, various embodiments relate to systems including stent - grafts, and to methods of manufacturing such stent - grafts, and to methods of treating aneurysms using such stent - grafts. Background Art

[0004] An aneurysm is a medical condition characterized by the dilation and weakening of a person's arterial wall. Aneurysms can form (develop) at different locations within an artery. For example, thoracic or abdominal aortic aneurysms can occur in the human body. Such a medical condition is serious and potentially life - threatening, thus requiring medical intervention to treat the condition. Existing systems and methods for treating such a condition include invasive surgeries where the affected blood vessel or body cavity is replaced by a graft.

[0005] Due to the risk factors inherent in the surgical repair of arteries or arterial walls, surgeries for treating aneurysms are associated with relatively high morbidity and mortality rates. A long and painful recovery is usually required, resulting in substantial medical costs. Due to the inherent risks and complexity of surgical repair of aortic aneurysms, endovascular repair has become a widely used alternative therapy.

[0006] In endovascular repair, an expandable stent - graft is placed within the damaged artery to reinforce the weakened portion of the arterial wall. The stent - graft is a fabric tube supported by a scaffold or wire stent. The stent - graft has several layers of material (such as polytetrafluoroethylene (PTFE)) around the scaffold. To perform endovascular repair of an aneurysm, a surgeon typically makes a small incision in the patient's groin and inserts a compressed stent - graft delivery system through the incision into the blood vessel and into the location of the aneurysm. Then the stent - graft is expanded within the artery to reinforce the damaged arterial wall. Summary of the Invention

[0007] Various embodiments provide enhancements in the compression and expansion of stent-grafts to facilitate insertion into one or more blood vessels of a patient. Various embodiments provide intravascular stent-graft compression by: disposing a plurality of graft material layers around a stent member; forming channels with graft material around each stent member; placing reduction bands on the stent member within channels located between the graft material layers; and providing release lines passing through end loops of the reduction bands to readily release the reduction bands when desired, thereby allowing the stent-graft to expand.

[0008] In some embodiments, a stent-graft system includes a stent-graft, one or more reduction bands (such as sutures or threads), and a release line or locking line. In various embodiments, the graft material for the stent-graft is formed to have integrally formed channels that surround each of one or more stent members. In some embodiments, the one or more reduction bands are made of silk thread or thread, and each reduction band passes through a shape defined by the graft material around a corresponding stent member. In various embodiments, each reduction band has a length that is less than the circumference of the corresponding stent member when fully expanded but greater than the circumference of the stent member when in a compressed state, such that it can hold the stent member in a compressed state. In some embodiments, each reduction band has loops at both ends, and the release line is configured to pass through the two loops of the reduction band when the stent-graft is in a compressed state. The release line is then pulled out from the loops of the reduction band, allowing the stent-graft to expand radially.

[0009] A stent-graft system according to an embodiment includes a first graft material layer, a second graft material layer, a stent member, and a reduction band. The stent member is located between the first graft material layer and the second graft material layer. The reduction band is at least partially located within a channel between the second graft material layer and the first graft material layer and around at least a portion of the stent member.

[0010] In various embodiments, the second graft material layer has a shape that provides a channel between the second graft material layer and the first graft material layer. In various embodiments, the reduction band has a length that is shorter than the circumference of the stent member when fully expanded but longer than the circumference of the stent member when in a compressed state. In some embodiments, the reduction band includes loops, and corresponding ones of the loops are at each end of the reduction band. Additionally, in some embodiments, the stent-graft system further includes a release line that passes through the loops of the reduction band.

[0011] In various embodiments, the stent member can radially expand from a compressed state to a decompressed state, and the constriction band is releasable to permit the stent member to expand from the compressed state to the decompressed state. In some embodiments, the stent graft system further comprises: a second stent member positioned between a first graft material layer and a second graft material layer; and a second constriction band at least partially positioned in a second channel between the second graft material layer and the first graft material layer and around at least a portion of the second stent member.

[0012] In some embodiments, the second graft material layer has a shape that provides a second channel between the second graft material layer and the first graft material layer. Additionally, in some embodiments, the constriction band comprises a loop and the second constriction band comprises a loop, and the stent graft system further comprises a release wire that passes through the loop of the constriction band and through the loop of the second constriction band. In some embodiments, the stent graft system further comprises: a pleat in the second graft material layer between the stent member and the second stent member.

[0013] A method of manufacturing a stent graft system according to an embodiment includes: placing a plurality of stent members on a first graft material layer; placing a respective spacer of a plurality of spacers at least partially around each of the plurality of stent members; encapsulating at least a portion of each of the plurality of spacers with a second graft material layer; and removing each of the plurality of spacers from a respective opening in the second graft material layer to leave a respective channel between the second graft material layer and the first graft material layer around each of the plurality of stent members. In various embodiments, each of the plurality of spacers comprises a tube.

[0014] In various embodiments, the method further comprises placing a respective constriction band of a plurality of constriction bands at least partially around each of the plurality of stent members in the respective channel. In some embodiments, each of the plurality of constriction bands comprises a silk thread. In some embodiments, each of the plurality of constriction bands comprises a loop, and the method further comprises placing a release wire to pass through the loop of each of the plurality of constriction bands to maintain the plurality of stent members in a radially compressed state. In some embodiments, the constriction bands are positioned such that an end of each of the plurality of constriction bands extends out of a respective opening in the second graft material layer.

[0015] In various embodiments, the method further includes: axially compressing a second graft material layer to form pleats in the second graft material layer; applying heat to set a crease for the pleats in the second graft material layer; and after the pleats have been heat-set, pulling on the second graft material layer to axially decompress the second graft material layer. In some embodiments, applying heat includes baking the second graft material layer in an oven to set a crease for the pleats in the second graft material layer.

[0016] The method according to an embodiment allows for the use of a stent graft system. The stent graft system includes a first graft material layer, a second graft material layer, a plurality of stent members, and a plurality of reduction bands. The method includes: positioning the stent graft system in a blood vessel, wherein each of the plurality of stent members is held in a compressed state by a corresponding reduction band of the plurality of reduction bands, the corresponding reduction band being at least partially located in a corresponding channel between the second graft material layer and the first graft material layer; and releasing the plurality of reduction bands to allow the plurality of stent members to expand from the compressed state to the decompressed state. In some embodiments, releasing the plurality of reduction bands includes pulling a release wire through a loop of one or more of the plurality of reduction bands and out of the loop of one or more of the plurality of reduction bands. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shows a stent graft system according to an embodiment.

[0018] Figure 2 Shows a section of a stent graft system according to an embodiment.

[0019] Figure 3 Shows a section of a stent graft system according to an embodiment.

[0020] Figure 4 Is a flow chart of a method for manufacturing a stent graft system according to an embodiment.

[0021] Figure 5 Shows a stent graft system during a manufacturing stage according to an embodiment.

[0022] Figure 6 Shows a stent graft system during another manufacturing stage according to an embodiment.

[0023] Figure 7 Shows a stent graft system during yet another manufacturing stage according to an embodiment.

[0024] Figure 8 Shows a stent graft system inserted into a blood vessel and in a compressed state according to an embodiment.

[0025] Figure 9 A stent graft system inserted into a blood vessel and in a decompressed state according to an embodiment is shown.

[0026] Figure 10 A flowchart of a method for deploying a stent graft system according to an embodiment in a blood vessel is shown.

[0027] Figure 11 A stent graft system inserted into a blood vessel and having an anchor stent for fixation according to an embodiment is shown.

[0028] Figure 12 A flowchart of a method for manufacturing a stent graft system according to an embodiment is shown. Detailed Description

[0029] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, like reference numerals generally refer to like items unless the context dictates otherwise. The illustrative 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 presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings, can be arranged, substituted, combined, and designed in a variety of different configurations, all of which are explicitly contemplated and form a part of the present disclosure.

[0030] Various embodiments provide a method for enhancing the compression and expansion of a stent graft by circumferentially disposing reduction bands (such as sutures or threads) around a stent member within a channel formed by a graft material. Various embodiments provide enhanced compression and expansion of the stent graft by: (1) providing a plurality of graft material layers around the stent member; (2) placing circumferential reduction bands on the stent member between the graft material layers; (3) providing release threads that pass through the ends of the reduction bands to easily release the reduction bands when desired, thereby allowing radial expansion of the stent member.

[0031] Various embodiments provide a stent graft system having circumferential reduction bands around a stent member. In various embodiments, the length of each reduction band is shorter than the circumference of the corresponding stent member when the stent member is in a fully expanded state, but its length is longer than the circumference of the corresponding stent member when the stent member is in a compressed state. When the stent member is in a compressed state, the reduction band surrounds the stent member. In various embodiments, each reduction band has loops at both ends of the reduction band. Release threads pass through the two loops of each reduction band surrounding each stent member to maintain compression of the stent member. In various embodiments, after the stent graft system is inserted into a blood vessel, the release threads are removed from the loops of the reduction bands to allow expansion of the stent member.

[0032] Figure 1 Illustrates a stent graft system 1 according to an embodiment. The stent graft system 1 includes: a first graft material layer 2a; a second graft material layer 2b; stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n; reduction bands 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 located between the first graft material layer 2a and the second graft material layer 2b. The second graft material layer 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 stent member 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 stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are circumferential channels.

[0033] Each of the reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n includes: corresponding first loops 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n at one end; and corresponding second loops 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n at the other end. Each of the reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is respectively located in the corresponding channels 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.

[0034] 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 reduced band 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n extend out from the corresponding openings 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second graft material layer 2b. When the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are in the compressed state, 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 reduced band 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n.

[0035] In various embodiments, each reduced band 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n has a length shorter than the circumference of 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 and longer than the circumference of the corresponding stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n when the stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n is in the compressed state. This allows the reduced bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n to keep the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n in the compressed state until the release wire 12 is pulled. Once the release wire 12 is pulled, the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n expand to the expanded state or the decompressed state.

[0036] The stent graft system 1 is a hollow tubular device having a first graft material layer 2a that forms a tubular wall and defines an open lumen. Although as Figure 1The stent graft 1 shown is depicted as being generally tubular, but those skilled in the art will understand that the stent graft system 1 can be of any shape suitable for delivery and placement at a target location in a patient. In various embodiments, both the first graft material layer 2a and the second graft material layer 2b comprise graft material made of one or more polymers or other suitable materials. In some embodiments, the first graft material layer 2a and the second graft material layer 2b are made of expanded polytetrafluoroethylene (ePTFE). In some embodiments, the first graft material layer 2a and the second graft material layer 2b are made of expanded polytetrafluoroethylene (ePTFE).

[0037] In some embodiments, the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are connected to each other as a single stent, while in some embodiments, the stent members are separated from each other. Each of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n can be made of, for example, stainless steel, nickel-titanium alloy (NiTi) (such as Nitinol), or any other suitable material, the other suitable materials including but not limited to 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 capable of radially expanding from a compressed state to an expanded state or a decompressed state. The stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n can be balloon-expandable or self-expandable. Although Figure 1 the illustrated embodiment shows a specific number of stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, it should be understood that any number of stent members can be used in various embodiments. In the illustrated embodiment, portions of the stent graft system 1 flare outwardly at both the proximal and distal ends, but in various other embodiments, the stent graft system can be uniform along its entire length.

[0038] Each stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n is compressed by a corresponding reduction band 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n to circumferentially reduce the diameter of the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n and to hold the stent members in a compressed state. In various embodiments, the reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n are sutures, threads, wires, etc.

[0039] The reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n surround the corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n and are all located in corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n between the first graft material layer 2a and the second graft material layer 2b. Each end of each reduction band 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 a second loop 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n, and the first loop and the second loop extend out from corresponding openings 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second graft material layer 2b. The release wire 12 passes through the first loop 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and the second loop 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n of each reduction band 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n and extends outwards at the proximal and distal ends of the stent graft system 1. When the release wire 12 is pulled, each reduction band 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n releases its compression on its corresponding stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n and the stent graft system 1 is allowed to radially expand.

[0040] Figure 2 Shows according to an embodimentFigure 1 A section of the stent graft system 1. The stent member 5a is located between the first graft material layer 2a and the second graft material layer 2b. The second graft material layer 2b is formed to provide a corresponding passage 3a around the stent member 5a. The reduction band 6a has a first loop 7a at the first end and a second loop 8a at the second end, and can extend out from an opening 4a in the second graft material layer 2b. The reduction band 6a is located in the passage 3a around the stent member 5a. The release wire 12 (refer to Figure 1 ) can pass through the first loop 7a and the second loop 8a of the reduction band 6a so that the reduction band 6a holds the stent member 5a in a compressed state.

[0041] Figure 3 shows a section of a stent graft system similar to Figure 2 , with like reference numerals referring to like elements, but further including an additional third graft material layer 2c, which is located between the stent member 5a and the second graft material layer 2b. Of course, in various other embodiments, any number of graft material layers can be used. Figure 3 In the embodiment of

[0042] Figure 4 is a flowchart of a method for manufacturing a stent graft system according to an embodiment. Figure 5 and Figure 6 show the stent graft system 10 during various manufacturing stages according to an embodiment, the stent graft system being manufactured to become Figure 1 the stent graft system 1 of Figure 7 . Also shown in Figure 1 、 Figure 4 、 Figure 5 and Figure 6, in step 100, the stent member is placed on the first graft material layer. For example, stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n are placed on the first graft material layer 2a. In step 110, corresponding spacers are placed around each stent member. For example, corresponding spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n are placed around each stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n. In various embodiments, each spacer 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n includes a tube or the like. In various embodiments, each spacer 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 spacer 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n includes polyimide or the like.

[0043] In step 120, the second graft material layer is used to encapsulate the spacers, and the ends of each spacer protrude from corresponding openings in the second graft material layer. For example, the second graft material layer 2b is used to encapsulate the spacers 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n, and the ends of each spacer 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n protrude from corresponding openings 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second graft material layer 2b.

[0044] In step 130, the stent graft system is axially compressed telescopically to form pleats in the graft material layer between the stent members. For example, the stent graft system 10 is axially compressed telescopically to form pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m in the second graft material layer 2b between the corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n (see Figure 6 ). Refer to Figure 4 and Figure 6, in step 140, heat is applied to the stent-graft system to set the creases of the pleats in the graft material layer. For example, while the stent-graft system 10 is telescopically compressed, heat is applied to the stent-graft system, thereby setting the creases of pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m.

[0045] In various embodiments, the application of heat is performed by applying a soldering iron to pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m to set the creases of pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m. In some embodiments, the application of heat is performed by placing the stent-graft system 10 in an oven to bake the stent-graft system 10 for a predetermined period of time, thereby thermally locking the creases of 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 crease or a folded surface of the graft material, and the crease or the folded surface is formed in the region between the positions 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, 11m is disposed between the crowns formed by two corresponding stent members among the stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n.

[0046] In step 150, after the pleats have been thermally set, the stent-graft system is pulled to decompress the graft material layer. For example, after the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m have been thermally set, the stent-graft system 10 Figure 6 is pulled in the longitudinal direction to decompress the stent-graft system 10 in the longitudinal direction. Refer to Figure 1 ,Figure 4 , Figure 5 , Figure 6 and Figure 7 , in step 160, each spacer is removed from the corresponding opening in the second graft material layer, thereby leaving a corresponding circumferential channel around each stent member. For example, each spacer 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l, 9m, 9n of the stent-graft system 10 is removed from the corresponding openings 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second graft material layer 2b, thereby leaving corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around each stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, as in the resulting stent-graft system 1.

[0047] Referring to Figure 1 , Figure 4 and Figure 7 , in step 170, a corresponding reduction band is placed around each stent member in the corresponding channel, the reduction band having an end loop extending from the corresponding opening in the second graft material layer. For example, a corresponding one of the reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is placed around each stent member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n in the corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n, the reduction band having an end loop extending from the corresponding openings 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n in the second graft material layer 2b. In step 180, a release wire is passed through the end loop of each reduction band to hold the stent member in a radially compressed state. For example, the release wire 12 is passed through the corresponding first loops 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n and the corresponding second loops 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n of each reduction band 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 a radially compressed state. Figure 7Illustrates an example of a manufacturing stage for inserting a release wire 12 for a stent graft system 1. In various embodiments, a cylindrical device 30 with an open end is used to hold the stent graft system 1 when installing the release wire 12.

[0048] Figure 8 Illustrates an example of the stent graft system 1 in a compressed state Figure 1 being deployed in a blood vessel such as the aorta 20. Figure 9 Illustrates an example of the stent graft system 1 in a deployed and expanded state in the aorta 20. Figure 10 Illustrates a flowchart of a method for deploying a stent graft system (such as Figure 1 the stent graft system 1) in a blood vessel according to an embodiment. Figure 10 The described method allows the use of a stent graft system including a first graft material layer, a second graft material layer, a plurality of stent members, and a plurality of reduction bands.

[0049] Referring to Figure 1 , Figure 8 and Figure 10 , in step 200, the stent graft system is positioned in the blood vessel, and each stent member of the plurality of stent members is held in a compressed state by a corresponding reduction band of the plurality of reduction bands, and the corresponding reduction band is at least partially located in a corresponding channel between the second graft material layer and the first graft material layer. For example, the stent graft system 1 having reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n is positioned in the aorta 20, where the reduction bands 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n are located in corresponding channels 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n around the corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n between the first graft material layer 2a and the second graft material layer 2b.

[0050] In various embodiments, the stent graft system 1 allows controlled and precise deployment, thereby allowing repositionability. In various embodiments, the creases of the pleats 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h, 11i, 11j, 11k, 11l, 11m between the corresponding stent members 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n make the stent graft system 1 more flexible within the aorta 20, as Figure 8As shown, the stent graft system 1 can be positioned to span the aneurysm 21 to repair the aorta 20.

[0051] Referring to Figure 1 , Figure 8 , Figure 9 and Figure 10 , in step 210, a plurality of constriction bands are released to allow a plurality of stent members to expand from a compressed state to a decompressed state, which is also the expanded state. In some embodiments, the release of the plurality of constriction bands includes step 220: pulling a release wire through a loop of one or more of the plurality of constriction bands and out of the loop of one or more of the plurality of constriction bands. For example, pulling the release wire 12 to release the constriction bands 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, and allowing the stent graft system 1 to radially expand within the aorta 20, thereby transitioning from the Figure 8 compressed state shown to the Figure 9 radially expanded state and decompressed state shown. As Figure 9 shown, the stent graft system 1 radially expands to contact at least a portion of the vessel wall (such as the wall of the aorta 20) and allows spanning of an aneurysm (such as an aneurysm in the aorta 20).

[0052] Figure 11 An embodiment of the stent graft system 1 is shown, wherein the stent graft system 1 further includes a stent anchor 50 at the proximal end of the stent graft system 1. The stent anchor 50 allows the stent graft system 1 to be fixed in a blood vessel (such as the aorta 20). In various embodiments, the stent anchor 50 includes barbs 51 or other fixing elements, and when the stent anchor 50 expands to the expanded state or decompressed state, the stent anchor 50 can radially expand from the compressed state to cause the barbs 51 to pierce the vessel wall (such as the wall of the aorta 20).

[0053] Referring to Figure 1 and Figure 2 , the stent graft system 1 according to an embodiment includes a first graft material layer 2a, a second graft material layer 2b, a stent member 5a, and a constriction band 6a. The stent member 5a is located between the first graft material layer 2a and the second graft material layer 2b. The constriction band 6a is at least partially located in a channel 3a between the second graft material layer 2b and the first graft material layer 2a and around at least a portion of the stent member 5a.

[0054] The second graft material layer 2b has a shape that provides a passage 3a between the second graft material layer 2b and the first graft material layer 2a. In various embodiments, Figure 1 the reduced band 6a of the stent graft system 1 has a length that is shorter than the circumference of the stent member 5a when the stent member 5a is fully expanded as Figure 9 shown, but longer than the circumference of the stent member 5a when the stent member 5a is in a compressed state as Figure 8 shown. Referring to Figure 1 and Figure 2 , in some embodiments, the reduced band 6a includes a first loop 7a and a second loop 8a at the ends of the reduced band 6a. Additionally, 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 band 6a.

[0055] The stent member 5a can radially expand from a compressed state to a decompressed state, and the reduced band 6a is releasable to allow the stent member 5a to expand from the compressed state to the decompressed state. The stent graft system 1 further includes: a stent member 5b located between the first graft material layer 2a and the second graft material layer 2b; and a reduced band 6b at least partially located in the passage 3b between the second graft material layer 2b and the first graft material layer 2a and around at least a portion of the stent member 5b.

[0056] The second graft material layer 2b has a shape that provides a passage 3b between the second graft material layer 2b and the first graft material layer 2a. Additionally, in some embodiments, the reduced band 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 reduced band 6a and through the first loop 7b and the second loop 8b of the reduced band 6b. As Figure 9 shown, in some embodiments, the stent graft system 1 further includes a crease caused by the wrinkles 11a in the second graft material layer 2b between the stent member 5a and the second stent member 5b.

[0057] Figure 12 is a flowchart of a method for manufacturing a stent graft system according to an embodiment. In step 300, a plurality of stent members are placed on the first graft material layer. In step 310, a respective spacer of the plurality of spacers is at least partially placed around each of the plurality of stent members. In step 320, the second graft material layer is used to encapsulate at least a portion of each of the plurality of spacers.

[0058] In step 330, the second graft material layer is axially compressed to form pleats in the second graft material layer. In step 340, heat is applied to set creases for the pleats in the second graft material layer. In some embodiments, applying heat includes baking the second graft material layer in an oven to set creases for the pleats in the second graft material layer. In step 350, after the pleats have been thermally set, the second graft material layer is pulled to axially decompress the second graft material layer. In step 360, each of the plurality of spacers is removed from a corresponding opening in the second graft material layer to leave a corresponding passage around each of the plurality of stent members between the second graft material layer and the first graft material layer. In various embodiments, each of the plurality of spacers includes a tube.

[0059] In step 370, a corresponding reduction band of the plurality of reduction bands is at least partially placed in the corresponding passage around each of the plurality of stent members. In some embodiments, each of the plurality of reduction bands includes a silk thread. In some embodiments, each of the plurality of reduction bands includes a natural or synthetic fiber. In some embodiments, each of the plurality of reduction bands includes a metal. In some embodiments, each of the plurality of reduction bands includes a loop. In step 380, a release wire is placed to pass through the loop of each of the plurality of reduction bands to hold the plurality of stent members in a radially compressed state. In some embodiments, the reduction bands are positioned such that the ends of each of the plurality of reduction bands extend out of the corresponding opening in the second graft material layer.

[0060] In various embodiments, the release wire extends through the stent graft system to lock reduction bands (such as sutures, etc.) in place around the stent members. The release wire can then be removed from the loop of the suture to release the suture and allow the stent members to expand. When the stent members expand, the stent graft system provides a radially outward force on the wall of the aorta. In various embodiments, the stent graft system serves to reinforce the wall of a weakened aorta, such as may be caused by an aneurysm.

[0061] In various embodiments, during the manufacture of a stent graft system, a tube is wrapped around a first graft material layer and a stent member. Then, the stent member, the first graft material layer, and the tube are encapsulated with another graft material layer, thereby forming a channel between the two graft material layers, wherein the tube is located within the channel. In various embodiments, heat is used to thermally pleat the graft material layers. In various embodiments, the tube is removed from between the graft material layers, which leaves a channel on each stent member. In some embodiments, sutures are placed around each stent member in corresponding channels between the graft material layers to replace the tube and maintain compression of the stent member. In various embodiments, a release wire is inserted through a loop of the suture, traveling from the distal end to the proximal end of the stent graft system to lock the suture in place and maintain compression of the stent member. In various embodiments, pulling the release wire releases the suture, thereby allowing the stent member to expand. After the stent graft system is inserted into the correct position within an artery (such as the aorta) of a patient, the release wire can be removed.

[0062] In various embodiments, the stent member can be attached to or laminated to one or more graft material layers. In various embodiments, the stent member is fully laminated or welded within one or more graft material layers. In some embodiments, the stent member is partially laminated or free-floating within or between one or more graft material layers. In some embodiments, the graft material layer extends over the entire length of the stent graft system from the proximal end to the distal end. In some other embodiments, the graft material layer does not cover the entire length of the stent graft system, leaving a portion of the distal end and / or proximal end exposed, which can expose some stent members at either end.

[0063] In various embodiments, during manufacture, there is a tube surrounding the stent member. In various embodiments, each stent member has a separate tube piece, and the separate tube piece circumferentially surrounds the stent member. In some embodiments, the tube pieces can be connected at various points. In some embodiments, the tube can consist of a single piece helically wound around some or all of the stent members. In various embodiments, the stent member is at least partially laminated between the graft material layers.

[0064] In various embodiments, during manufacture, the stent graft system is longitudinally compressed from a longitudinally extended configuration to a compressed configuration and then thermally pleated to form a plurality of circumferential pleats in a predetermined orientation such that the pleated segments of the stent graft system nest with each other along an axis. In various embodiments, the circumferential pleats can be thermally pleated in any orientation to lock the pleats in that orientation such that when the stent graft is longitudinally compressed again or angled under natural settings (e.g., after implantation of the stent graft system), the compressed stent graft will memorize and resume the preset pleat orientation.

[0065] In various embodiments, the release wire passes through loops in each suture around each stent member, thus compressing each stent member. In various other embodiments, the release wire may pass through loops in sutures on only a portion of the stent members. Some embodiments may have multiple release wires, each for releasing a reduction band around a corresponding subset of the stent members. In various embodiments, the release wire acts as a locking mechanism, such that the suture is held tightly in a circumferentially surrounding position around the stent member until the release wire is pulled. In various embodiments, when the release wire is removed from the suture, the loop of the suture is released and the suture no longer tightly surrounds the stent member, thereby allowing the stent member to decompress into a radially expanded state.

[0066] In various embodiments, a stent graft system according to an embodiment is deployed in the aortic arch. In some embodiments, a stent graft system according to an embodiment is inserted into the descending aorta portion of the aorta. In various embodiments, the stent graft system has stent members that are configured to allow the stent graft system to bend to conform to the shape of the aorta. In various embodiments, when the stent members expand, the stent graft system provides a radially outward force on the wall of the aorta. In various embodiments, the stent graft system includes a branch portion to extend into one or more additional blood vessels.

[0067] Various embodiments provide improved compression and controlled expansion of a stent graft system when deployed within a patient. Reduction bands circumferentially surround the stent members of the stent graft system. In some embodiments, a release wire passes through loops extending out of channel openings in the graft material of the reduction band, and the release wire extends at opposite ends of the stent graft system. Removal of the release wire relaxes the reduction band to allow the stent members of the stent graft system to fully expand. The reduction band and the release wire allow the stent graft system to be deployed in one or more blood vessels in a controlled and precise manner.

[0068] A stent graft system according to an embodiment includes a first graft material layer, a second graft material layer, one or more stent members, one or more reduction bands, and a release wire. In various embodiments, the one or more stent members are located between the first graft material layer and the second graft material layer, and the second graft material layer 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 reduction bands has loops at opposite ends and is located in a corresponding channel around a corresponding one of the stent members, and the reduction band has a length shorter than the circumference of the corresponding stent member when the corresponding stent member is fully expanded, but longer than the circumference of the corresponding stent member when the stent member is in a compressed state. In various embodiments, when the one or more stent members are in a compressed state, the release wire passes through two loops of each of the one or more reduction bands.

[0069] In all respects, the embodiments disclosed herein should be considered illustrative and not restrictive of the present invention. The present invention is in no way limited to the above embodiments. Various modifications and changes can be made to the embodiments without departing from the spirit and scope of the present invention. All modifications and changes that fall within the meaning and scope of the equivalents of the claims are intended to fall within the scope of the present invention.

Claims

1. A stent graft system, comprising: A first graft material layer; A second graft material layer; A stent member located between the first graft material layer and the second graft material layer; And A constriction band at least partially located in a channel between the second graft material layer and the first graft material layer and circumferentially extending around at least a portion of the stent member to hold the stent member in a radially compressed state, releasing the constriction band allowing the stent member to expand from the compressed state to a decompressed state.

2. The stent graft system according to claim 1, Among them, Wherein the second graft material layer has a shape providing the channel between the second graft material layer and the first graft material layer.

3. The stent graft system according to claim 1, Among them, Wherein the constriction band has a length shorter than the circumference of the stent member when the stent member is fully expanded, but longer than the circumference of the stent member when the stent member is in the compressed state.

4. The stent graft system according to claim 1, Among them, Wherein the constriction band includes a loop and has a corresponding loop in the loop of the constriction band at each end thereof.

5. The stent graft system according to claim 4, further comprising: A release wire passing through the loop of the constriction band.

6. The stent graft system according to claim 1, Among them, Wherein the stent member can radially expand from the compressed state to the decompressed state; Wherein the constriction band is releasable to allow the stent member to expand from the compressed state to the decompressed state.

7. The stent graft system according to claim 1, further comprising: A second stent member located between the first graft material layer and the second graft material layer; And A second constriction band at least partially located in a second channel between the second graft material layer and the first graft material layer and around at least a portion of the second stent member.

8. The stent graft system according to claim 7, Among them, Wherein the second graft material layer has a shape providing the second channel between the second graft material layer and the first graft material layer.

9. The stent graft system according to claim 7, Among them, Wherein the constriction band includes a loop and the second constriction band includes a loop; and Wherein the stent graft system further comprises a release wire passing through the loop of the constriction band and through the loop of the second constriction band.

10. The stent graft system according to claim 7, further comprising: Folds in the second graft material layer between the stent member and the second stent member.

11. A method of manufacturing a stent graft system, the method comprising: Placing a plurality of stent members on a first graft material layer; Placing a respective spacer of a plurality of spacers at least partially around each of the plurality of stent members; Encapsulating at least a portion of each of the plurality of spacers using a second graft material layer; And Remove each of the plurality of spacers from the respective opening in the second graft material layer to leave a respective passage around each of the plurality of stent members between the second graft material layer and the first graft material layer. Place a respective constriction band of the plurality of constriction bands at least partially around each of the plurality of stent members in the respective passage and extending circumferentially around at least a portion of the stent member to hold the stent member in a radially compressed state, and releasing the constriction band allows the stent member to expand from the compressed state to the decompressed state.

12. The method according to claim 11, Among them, Each of the plurality of spacers includes a tube.

13. The method according to claim 11, Among them, Each of the plurality of constriction bands includes a thread.

14. The method according to claim 11, Among them, Each of the plurality of constriction bands includes a loop; and wherein the method further includes placing a release wire through the loop of each of the plurality of constriction bands to hold the plurality of stent members in a radially compressed state.

15. The method according to claim 11, Among them, Position the constriction band such that an end of each of the plurality of constriction bands extends out of the respective opening in the second graft material layer.

16. The method according to claim 11, further comprising: Axially compressing the second graft material layer to form a fold in the second graft material layer; Applying heat to set a crease for the fold in the second graft material layer; and After the fold has been thermally set, pulling the second graft material layer to axially decompress the second graft material layer.

17. The method according to claim 16, Among them, The applying heat includes baking the second graft material layer in an oven to set a crease for the fold in the second graft material layer.

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