VASCULAR PROSTHESIS

Abstract

The present invention relates to a vascular prosthesis for a blood vessel of a patient, comprising: a hollow cylindrical main body having a prosthetic material, a longitudinal axis (L), and a stent frame, wherein the main body includes proximal and distal openings at proximal and distal ends, and wherein the vascular prosthesis having a first terminal stent ring attached to the prosthetic material at at least one end, and wherein the vascular prosthesis has at least one thread element attached thereto, wherein the at least one thread element reduces the diameter of the respective distal or proximal opening by tensile loading.

Claims

1. A vascular prosthesis for a blood vessel of a patient, comprising: a hollow cylindrical main body having a stent frame and a prosthetic material attached thereto, the main body having a longitudinal axis (L), an inner side and an outer side, and a proximal end with a proximal opening and a distal end with a distal opening, a first self-expanding terminal stent ring provided at the proximal end and/or distal end, which stent ring can be transferred from a compressed state to an expanded state, wherein the first stent ring is meanderingly circumferential and has pointed arches and struts connecting the same, and wherein the first stent ring is attached to the prosthesis material on the outer side of the main body in such a way that no pointed arch of the first stent ring projects freely beyond the proximal and/or distal end, and at least one thread element provided on the first stent ring, which thread element has a first end and a second end, and wherein the thread element is fixed with its first end to the vascular prosthesis and is guided at least partially circumferentially movably on the vascular prosthesis in such a way that the first stent ring can be transferred from a radially compressed state into an expanded state via a tensile load or tensile relief of the at least one thread element.

2. The vascular prosthesis according to claim 1, wherein at the proximal and/or distal end a second terminal stent ring is provided, which can be transferred from a radially compressed state to an expanded state via the compression and/or expansion of the first stent ring, wherein the second stent ring is meanderingly circumferential and has pointed arches and struts connecting them and wherein the second stent ring is fixed to the prosthesis material on the inner side of the main body in such a way that no pointed arch of the second stent ring projects freely beyond the proximal and/or distal end.

3. The vascular prosthesis according to claim 1, wherein the at least one thread element is fixed with its first end to the vascular prosthesis in a region in which the first or second terminal stent ring is fixed to the prosthesis material, and in particular is fixed firmly to the prosthesis material and/or to the first or second terminal stent ring.

4. The vascular prosthesis according to claim 1, wherein the at least one thread element is alternately threaded over and under struts of the first stent ring.

5. The vascular prosthesis according to claim 1, wherein the second end of the thread element has a loop via which the thread can be detachably fixed to a vascular prosthesis insertion system.

6. The vascular prosthesis according to claim 1, wherein the at least one thread element is guided at least at one point in the circumferential direction of the first stent ring between two spaced-apart seams, the two spaced-apart seams securing the first stent ring to the prosthesis material.

7. The vascular prosthesis according to claim 1, wherein between 2 and 8, in particular 2, 3, 4, 5, 6, 7, or 8 thread elements are provided.

8. The vascular prosthesis according to claim 7, wherein the pointed arches of the first and the second terminal stent ring are arranged non-overlapping at the proximal and/or distal end on the outer side and the inner side on the main body, and that the first and second stent ring, separated by the prosthesis material, intersect at the struts.

9. The vascular prosthesis according to claim 1, wherein the at least one first terminal stent ring has struts of equal length.

10. The vascular prosthesis according to claim 1, wherein the second terminal stent ring has struts of different length.

11. The vascular prosthesis according to claim 1, wherein in the second terminal stent ring pointed arches are provided which point towards the proximal or distal opening of the vascular prosthesis and which have a uniform height, as well as pointed arches which point away from the opening of the vascular prosthesis and which have a non-uniform height.

12. The vascular prosthesis according to claim 1, wherein the vascular prosthesis has outgoing side branches.

13. The vascular prosthesis according to claim 1, wherein the stent frame further comprises non-terminal stent rings which are distributed one behind the other over the hollow-cylindrical main body and are attached to the prosthesis material on its inner side and/or outer side.

14. The vascular prosthesis according to claim 1, wherein the stent frame further comprises a laser-cut or perforated stent attached to the prosthetic material at the inner side and/or outer side of the hollow cylindrical main body.

15. A delivery system for inserting a vascular prosthesis having at least a first terminal stent ring into a blood vessel of a patient, wherein the delivery system comprises, a catheter tube onto which the vascular prosthesis can be loaded for insertion into the blood vessel, a retraction sheath for compressing the vascular prosthesis in its loaded state, and a fixation axially movable on the catheter tube, and at least one thread element via which the terminal stent ring of the vascular prosthesis can be compressed or expanded by tensile loading or unloading.

16. The delivery system according to claim 15, which is designed for inserting a vascular prosthesis comprising: a hollow cylindrical main body having a stent frame and a prosthetic material attached thereto, the main body having a longitudinal axis (L), an inner side and an outer side, and a proximal end with a proximal opening and a distal end with a distal opening, a first self-expanding terminal stent ring provided at the proximal end and/or distal end, which stent ring can be transferred from a compressed state to an expanded state, wherein the first stent ring is meanderingly circumferential and has pointed arches and struts connecting the same, and wherein the first stent ring is attached to the prosthesis material on the outer side of the main body in such a way that no pointed arch of the first stent ring projects freely beyond the proximal and/or distal end, and at least one thread element provided on the first stent ring, which thread element has a first end and a second end, and wherein the thread element is fixed with its first end to the vascular prosthesis and is guided at least partially circumferentially movably on the vascular prosthesis in such a way that the first stent ring can be transferred from a radially compressed state into an expanded state via a tensile load or tensile relief of the at least one thread element.

17. The delivery system according to claim 15, wherein the fixation is designed in such a way that via its axial displacement on the catheter tube the at least one thread element can be compressed or expanded by tension loading or tension relief of the first stent ring, and via the latter, if necessary, of the second stent ring.

18. A method of inserting a vascular prosthesis into a blood vessel of a patient by means of a delivery system, the vascular prosthesis comprising: a hollow cylindrical main body having a stent frame and a prosthetic material attached thereto, the main body having a longitudinal axis (L), an inner side and an outer side, and a proximal end with a proximal opening and a distal end with a distal opening, a first self-expanding terminal stent ring provided at the proximal end and/or distal end, which stent ring can be transferred from a compressed state to an expanded state, wherein the first stent ring is meanderingly circumferential and has pointed arches and struts connecting the same, and wherein the first stent ring is attached to the prosthesis material on the outer side of the main body in such a way that no pointed arch of the first stent ring projects freely beyond the proximal and/or distal end, and at least one thread element provided on the first stent ring, which thread element has a first end and a second end, and wherein the thread element is fixed with its first end to the vascular prosthesis and is guided at least partially circumferentially movably on the vascular prosthesis in such a way that the first stent ring can be transferred from a radially compressed state into an expanded state via a tensile load or tensile relief of the at least one thread element; the delivery system comprising: a catheter tube onto which the vascular prosthesis can be loaded for insertion into the blood vessel, a retraction sheath for compressing the vascular prosthesis in its loaded state, and a fixation axially movable on the catheter tube, and wherein the method comprises the following steps: inserting a vascular prosthesis loaded onto a catheter tube and held compressed by a retraction sheath into a blood vessel of a patient; removing the retraction sheath to release a major portion of the vascular prosthesis, leaving the proximal or distal end fixed and compressed; axially displacing the fixation to relieve the at least one thread member and thereby expanding the distal or proximal end; and releasing the thread element from the fixation of the delivery system to fully release the distal or proximal end of the vascular prosthesis.

19. A method for treating of a vascular disease of a patient in need thereof, the method comprising the step of implanting a vascular prosthesis in a vessel of the patient to be treated, the vascular prosthesis comprising: a hollow cylindrical main body having a stent frame and a prosthetic material attached thereto, the main body having a longitudinal axis (L), an inner side and an outer side, and a proximal end with a proximal opening and a distal end with a distal opening, a first self-expanding terminal stent ring provided at the proximal end and/or distal end, which stent ring can be transferred from a compressed state to an expanded state, wherein the first stent ring is meanderingly circumferential and has pointed arches and struts connecting the same, and wherein the first stent ring is attached to the prosthesis material on the outer side of the main body in such a way that no pointed arch of the first stent ring projects freely beyond the proximal and/or distal end, and at least one thread element provided on the first stent ring, which thread element has a first end and a second end, and wherein the thread element is fixed with its first end to the vascular prosthesis and is guided at least partially circumferentially movably on the vascular prosthesis in such a way that the first stent ring can be transferred from a radially compressed state into an expanded state via a tensile load or tensile relief of the at least one thread element.

20. The method of claim 19, wherein the vascular prosthesis is implanted into the vessel by means of a delivery system, the delivery system comprising: a catheter tube onto which the vascular prosthesis can be loaded for insertion into the blood vessel, a retraction sheath for compressing the vascular prosthesis in its loaded state, and a fixation axially movable on the catheter tube.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0099] Examples of embodiments of the invention are shown in the drawings and will be explained in more detail in the following description. Showing:

[0100] FIG. 1A a schematic representation of a first embodiment of a vascular prosthesis according to the invention;

[0101] FIG. 1B a schematic representation of a second embodiment of a vascular prosthesis according to the invention;

[0102] FIG. 1C a magnified view of the proximal end region of the embodiments shown in 1A and 1B; and

[0103] FIG. 2 a schematic representation of a section of a vascular prosthesis according to the invention, with the vascular prosthesis opening partially open, with the thread elements still attached to the insertion/delivery system.

EMBODIMENTS

[0104] FIGS. 1A and 1B show two embodiments of an exemplary vascular prosthesis according to the invention, which differ in a different distal end region, as will be explained below. The reference signs are the same for the corresponding features in both figures, although not all features in FIGS. 1A and 1B have been given reference signs for reasons of clarity.

[0105] In FIGS. 1A and 1B, 10 (FIG. 1A, and 100 (FIG. 1B) show/designate, respectively, in total a schematic, not to scale representation of a first embodiment of the vascular prosthesis according to the invention for implantation into a blood vessel of a patient, wherein the vascular prosthesis 10, 100 in the representation shown in FIGS. 1A and 1B is in the expanded state.

[0106] The vascular prosthesis 10, 100 has a hollow cylindrical base or main body 11 with a prosthetic material 12 and a stent frame 13 attached thereto, which in the embodiment shown in FIG. 1 is a stent frame 13 comprising a plurality of stent rings, 13a, 13b, 13c, 13d, 13e, arranged in series. It is understood that, as explained further above, the stent frame 13 may also be in the form of a lasered or braided stent frame, in which cases the stent frame has cells between the braided or lasered stent material.

[0107] The vascular prosthesis 10, 100 in FIGS. 1A and 1B has a proximal end 14 and a distal end 15 with a proximal opening 14a and a distal opening 15a, a longitudinal axis L, and an outer surface/side 20 and an inner surface/side 21.

[0108] The proximal end 14 further includes a first terminal stent ring 22 and a second terminal stent ring 23, indicated by dashed lines in FIGS. 1A and 1B. In the embodiment shown in FIGS. 1A and 1B, the stent ring 22 is attached to the outer surface 20 of the vascular prosthesis 10, 100, and the second terminal stent ring 23 is attached to the inner surface 21 of the vascular prosthesis 10, 100.

[0109] In the embodiment shown in FIGS. 1A and 1B, the stent rings, 13a to 13e, 22 and 23 have pointed arches 24 and which point alternately in the proximal direction p and distal direction d, and which are connected to one another via struts/legs 25. The stent rings 13a to 13b, 22 and 23 are fixed to the prosthetic material by sutures 27, which are indicated by dashes in the figures.

[0110] As can be seen from FIG. 1, the prosthetic material and the outermost tips of the proximally facing pointed arches 24 of the terminal stent springs 22 and 23 are flush with each other so that no pointed arch protrudes freely beyond the prosthetic material 12, and so that both stent rings 22, 23 are completely covered by the prosthetic material 12.

[0111] The distal end 15 of the vascular prosthesis 10, 100 is different in FIGS. 1A and 1B in that the distal end 15 of the vascular prosthesis 10 shown in FIG. 1A has a terminal stent ring 26 with portions of its pointed arches 24 and struts 25 projecting beyond the prosthetic material 12.

[0112] In the distal end 15 of the vascular prosthesis 100 shown in FIG. 1B, the distal end 15, like the proximal end 14, is formed of stent rings 22, 23 fully covered with prosthetic material 12.

[0113] FIG. 1B shows an enlarged section of the proximal end 14 of the vascular prosthesis 10 of FIG. 1A, although according to the invention the distal end 15 can also or alternatively have the same design. The vascular prosthesis 10 has an outer surface/side 16 facing a vessel wall after implantation and an inner surface/side 17 facing the blood flow.

[0114] As can be seen from FIGS. 1A and 1B, the vascular prosthesis 10 has two stent rings on 18, 19 at the end portion, a first terminal stent ring 18 fixed to the outer side 16 of the vascular prosthesis 10 and a second terminal stent ring 19 fixed to the inner side 17 of the vascular prosthesis 10. The two stent rings 18, 19 are thereby fixed to the prosthesis material 12 by means of sutures 20, the sutures 20 not being distributed over the entire stent ring 18, 19, but being spaced apart from one another at specific intervals and at specific locations.

[0115] FIG. 10 shows an enlarged view of the proximal end 14 of the vascular prostheses 10, 100.

[0116] Two thread elements 30a and 30b are provided thereon, each having a first end 31a, 31b and a second end 32a (the second end of the second thread element 30b is not shown), and a length Q extending therebetween. In each case, the first end 31a, 31b is fixedly secured to the prosthetic material 12 via the stent ring 23 attached to the proximal end 14 from the inner side 24.

[0117] For reasons of clarity, only two thread elements 30a, 30b are shown in FIG. 10; further thread elements are provided in principle in the embodiment shown in FIG. 1 in order to compress the stent ring 22 and the stent ring 23 as a whole and thus to be able to close the opening 14a of the vascular prosthesis 10, 100.

[0118] The fixation may be performed at a strut 25 and/or pointed arch 24, for example by means of gluing and/or sewing to the stent ring 22 or 23 and/or to the prosthesis material 12.

[0119] The second end 32 of the thread element 30a has a loop 33. Starting from its fixing point 34a, the thread element 30a is alternately guided movably in the circumferential direction U over a first strut 25a and then under a second strut 25b. As can be seen from FIG. 10, the thread element 30a spans with its length Q essentially three pointed arches 24, two pointed arches pointing proximally p and one pointed arches 24 pointing distally d.

[0120] As mentioned above, further thread elements 30 (not shown) are provided in circumferential direction U to close and open the proximal opening 14a of the vascular prosthesis 10, 100. Each of these spans subsequent pointed arches or struts in the circumferential direction U.

[0121] Finally, the thread element 30a is passed between two spaced apart sutures 36, 37 at location 35 in the circumferential direction U of the terminal stent ring 22, thereby forming a deflection for the thread element 30a. The two spaced seams/sutures 36, 37 may be the same as those used to attach the stent ring 22 to the prosthetic material 21.

[0122] The thread element 30a is guided on the stent ring 22 in such a way that the thread element 30, at least at this point 35, can move only to a very limited extent proximally p and distally d, i.e. in the area bounded by the two seams/sutures 36, 37, while on the other hand it can be guided movably in the circumferential direction u.

[0123] When the thread element 30a is pulled at the second end 32a, the tensile load compresses the portion of the stent ring 22 traversed by the thread element 30a due to the deflection formed by the two seams/sutures 36, 37. With a proximal tensile load, the loop 33a or the second end 32a of the thread element 30a can be extended beyond the proximal end 14 of the vascular prosthesis 10, 100 and, when loaded onto an insertion/delivery system (discussed below), can be releasably hooked/fastened into it via the loop 33a.

[0124] In the same manner, the second (and any further thread element 30) thread element 30b can be guided and provided with a tensile load so that the stent ring section spanned by this thread element 30b can be compressed.

[0125] It is understood that the length of the thread elements 30a, 30b also determines their number: the longer the thread elements, the fewer are necessary to control the opening of the vascular prosthesis opening 14a and also the compression.

[0126] In the example shown in FIG. 1, 5 thread elements are provided.

[0127] FIG. 2 shows the proximal end 14 of the vascular prostheses shown in FIGS. 1A and 1B in a partially opened and expanded state, respectively: the first stent ring 22 and the second stent ring 23 of the vascular prosthesis 10, 100 are partially expanded, with the remaining portion of the vascular prosthesis 10, 100 still held compressed by a retraction sheath 40 of an insertion system 46 (which is shown only in part in FIG. 2).

[0128] FIG. 2 further shows four thread elements 30a, 30b, 30c, 30d, which are detachably secured with their respective second ends 32a, 32b, 32c, 32d into a fixation 42 of a catheter tube 44. The opening or expanding of the vascular prosthesis 10, 100 can be controlled as a function of the thread element length Q. After releasing this proximal fixation of the thread element 30a, 30b, 30c, 30d to the delivery system 46, for example by axially moving the fixation 42 in the direction of the arrow 45, the second ends 32a, 32b, 32c, 32d of the thread elements 30a, 30b, 30c, 30d are released and the vascular prosthesis 10, 100 can self-expand. Here, the thread elements 30a, 30b, 30c, 30d are again guided around the circumference of the vascular prosthesis 10, 100 via the respective deflection and placed in the blood vessel between the vascular prosthesis 10, 100 and vessel wall.

[0129] For loading the vascular prosthesis 10, 100 onto an insertion system 46, it is held compressed on a catheter tube 44 by a retraction sheath 40 about its longitudinal axis. The proximal end 14 (or distal end 15) or proximal opening 14a (distal opening 15a) of the vascular prosthesis 10, 100 is thereby additionally closed via the thread elements 30a, 30b, 30c, 30d by means of tensile loading by hooking the second ends 32a, 32b, 32c, 32d of the thread elements 30a, 30b, 30c, 30d into the fixation 42 via their loops 33.

[0130] The fixation shown in FIG. 2 is a system of several elongated fixation rods, preferably corresponding to the number of thread elements, which are axially movably/slidably guided in the catheter tube. Alternatively, multiple thread elements can also be mounted via one fixation rod. Details of an exemplary insertion system with a fixation as described herein are disclosed, for example, in EP 1 920 739, the contents of which are hereby made the subject matter in their entirety.

[0131] For insertion of the vascular prosthesis according to the invention into a blood vessel of a patient with the aid of an insertion system 46, the vascular prosthesis 10, 100, which is loaded onto the catheter tube 44 and held compressed by a retraction sheath 40, is inserted into a blood vessel of a patient, after proper placement thereof, the retraction sheath is removed to release the main portion of the vascular prosthesis 10, 100, leaving the proximal (or distal) end fixed and compressed and thus the corresponding opening of the vascular prosthesis closed. This allows repositioning of the vascular prosthesis to be easily effected, should this be necessary, without injuring the blood vessel at that location. Subsequently, the axial fixation is displaced to relieve the tension on the thread elements 30a, 30b, 30c, 30d, whereby the tension exerted on the thread elements 30a, 30b, 30c, 30d can be selectively and—if desired—gradually relieved, so that the opening 14a, 15a of the vascular prosthesis 10, 100 can also be gradually opened. Provided that the second ends of the thread elements 30a, 30b, 30c, 30d are released altogether from the fixation, the proximal/distal end 14, 15 of the vascular prosthesis 10, 100 is completely opened.