WO1997025001A1

WO1997025001A1 - Aortoiliac endoprosthesis

Info

Publication number: WO1997025001A1
Application number: PCT/FR1997/000005
Authority: WO
Inventors: Jean Marc Denis
Original assignee: Jean Marc Denis
Priority date: 1996-01-08
Filing date: 1997-01-02
Publication date: 1997-07-17
Also published as: EP0873093A1; FR2743293A1; FR2743293B1

Abstract

An aortoiliac endoprosthesis including two tapering tubes (2a) capable of being bent in all directions so that the upper tube ends (2b) have a greater diameter than the lower tube ends (2c), while sleeves (3, 4) are secured to each of the ends (2b, 2c). The sleeves (3, 4) are provided with hook means (5) for retaining the endoprosthesis (2), and made of a biocompatible, flexible shape-memory metal material.

Description

AORTO-ILIAC ENDOPROSTHESIS

The present invention relates to an aortoiliac stent for the treatment, for example, of aortic or aortoiliac aneurysms.

To date, the treatment of aortic or aorto-iliac aneurysms under renal are carried out by surgical way, either by endoluminal way.

In the first case, that is to say by surgery, the treatment is fairly delicate and requires fairly long anesthesia. Briefly, we proceed to an aneurysm intervention to put in place an aortic prosthesis. It is first necessary to have the upper and lower clamps on either side of the aneurysm. Then, the artery is cut at the aneurysm to allow the placement of the prosthesis which is sutured at each end of the artery. Finally, the prosthesis is wrapped in the thickness of the artery to isolate neighboring living elements. The blood circulation is then carried out by removing the forceps and the surgeon proceeds to close all of the living ancillary elements. It is noted that this operation is very delicate for the elderly and there are long-term parietal problems, that is to say risks of eventration.

In the second case, the treatment is carried out without surgical intervention. Indeed, the stents are introduced at a distance from the pathological area and positioned using a radiological installation. The principle is to bring the prosthesis or endoprosthesis to the site from an external femoral or iliac access, that is to say superficial and not very traumatic. The object of the present invention is to improve the endoluminal treatments in order to facilitate the placement of stents at the level of the aortic or aorto-bi-iliac aneurysm.

The aorto-iliac endoprosthesis according to the present invention comprises two tubes capable of deforming elastically in all directions and each end of which is integral with a mesh sleeve provided with attachment means, while said tubes have a conical profile so that their upper ends are of a larger diameter than that of their lower ends and that said sleeves are made of a bio-compatible metallic material, deformable and with shape memory.

The appended drawing, given by way of example, will allow a better understanding of the invention, the characteristics which it presents and the advantages which it is capable of providing:

Figure 1 is a schematic view showing the abdominal aorta provided with its various arteries.

Figure 2 is a perspective view illustrating the aortoiliac stent according to the present invention. Figure 3 is a view showing the positioning of the aortoiliac stent within the wall of the abdominal aorta.

Figure 4 is a view similar to that of Figure 3, but showing a variant implementation of the aorto-iliac stent.

Figures 5 and 6 are enlarged sections along V-V of Figure 3 and VI-VI of Figure 4 of the abdominal aorta at the upper fixation of the aortoiliac stent.

There is shown diagrammatically in FIG. 1 an abdominal aorta 1 dividing into a first artery 1a called “left primary iliac artery” and into a second artery 1b called “right primary iliac artery”. The abdominal aorta 1 has above the iliac arteries 1a and 1b a lower mesenteric artery 1c, a left renal artery 1d and a right renal artery 1e. The left primary iliac artery 1a is extended by a left external iliac artery 1g and by a left internal iliac artery 1i. Also, the right primary iliac artery 1b is extended by a right external iliac artery 1h and by a right internal iliac artery 1j.

An example of an aneurysm profile 1f of the abdominal aorta 1 which is located below the renal arteries 1d and 1e and which can extend over the primary iliac arteries 1a and 1b has been shown in dashed lines. In Figure 2, there is shown an aortoiliac stent 2 comprising two similar tubes 2a and of the same configuration. Each tube 2a is made of a bio-compatible material to avoid any rejection from neighboring living organs. The tubes 2a are provided with sufficient flexibility and elastic deformation in all their directions. The material preferably used for the manufacture of the tubes can for example be of the type called under the name "DACRON".

It can be seen that the tubes 2a are provided with an adequate length to respond to the treatment of aneurysms of the abdominal aorta 1 situated between the renal arteries 1d, 1e and the primary iliac arteries 1a, 1b.

For this, each tube 2a has a conical profile so that the upper ends 2b are of a larger diameter than that of the lower ends 2c.

The upper ends 2b cooperate respectively with a mesh sleeve 3. Each lower end 2c is connected to a mesh sleeve 4 of diameter smaller than that of the sleeves 3. The sleeves 3, 4 are provided in a metal alloy with shape memory. Each sleeve 3, 4 comprises, for example, small hooks 5, directed in direction from the outside and evenly distributed around the periphery of each sleeve. Each mesh sleeve 3, 4 penetrates inside the upper 2b and lower 2c ends of each tube 2a to extend the latter in their longitudinal direction. The hooks 5 are integral with the free ends of each sleeve 3, 4, that is to say those protruding at the end of each tube2a.

The endoprosthesis 2 is introduced inside the abdominal aorta 1 by the endoluminal route, that is to say by means of a particular bag device described in a patent application belonging to the Applicant.

Indeed, each tube 2a, integral with its sleeves 3, 4 is introduced by a bag device into the left external iliac artery 1g and right 1h respectively or the corresponding common femoral until its upper end 2b secured to the sleeve 3 is placed below the renal arteries 1d, 1e, while its lower end 2c provided with its sleeve 4 cooperates, depending on the operating case, with the primary iliac artery 1a, 1b or with the external iliac artery 1g, 1 h (Figure 3).

The upper ends 2b are deformed by means of special pocket devices so that the mesh sleeves 3 press each tube 2a against the internal wall of the abdominal aorta 1. It is noted that the hooks 5 of each sleeve 3 penetrate the wall internal of the abdominal aorta to improve the anchoring of the endoprosthesis 2. Likewise, the lower ends 2c are deformed by means of special pocket devices so that the mesh sleeves 4 of each tube 2a are pressed against the internal wall of the primary iliac artery 1a, 1b or against the internal wall of the external iliac artery 1g, 1h. It then suffices to remove the devices with particular bags to allow blood circulation to pass through the stent 2 and to permanently relieve the abdominal aorta 1 to prevent any rupture of the aneurysm 1f.

It is noted, after deformation of the upper ends 2b of the tubes 2a and of the sleeves 3 that the external periphery of each tube 2a on the one hand perfectly matches the internal wall of the abdominal aorta 1, and on the other hand is pressed against the outer periphery of the other tube to ensure a seal between said tubes 2a of the stent 2 (Figure 5). For this, provision is made for the diameter of the sleeves 3 to be sufficient to allow their simultaneous deformation to obtain the configuration of FIG. 5.

There is shown in Figures 4 and 6 a variant of the stent 2 according to the present invention, the upper end 2b of each tube 2a is secured to a sleeve 3 having the same configuration as those described above. It is noted that each sleeve 3 is in this case partially engaged inside the corresponding tube 2a. In fact, this solution is provided when the aneurysm 1f rises near the renal arteries 1d and 1e, thus eliminating part of the abdominal aorta 1 for fixing the stent 2. In this case, the sleeves 3 must come fix above the renal arteries 1d and 1e without the upper end 2b of each tube 2a obstructing them.

Thus, the sleeves 3 are deformed in the same manner as above, but the hooks 5 are fixed in the internal wall of the abdominal aorta 1 and above the renal arteries 1d and 1e, while the upper ends 2b of each tube 2a are located below the renal arteries 1d and 1e. The configuration of the sleeves 3 allows the flow of blood flow in the renal arteries 1d and 1e and this without obstructing them.

Similarly, the sleeves 4 of each tube 2a adapted to the lower end 2c may be engaged only partially so as to be able to anchor in the estiac iliac artery 1g, 1h without preventing the passage of blood flow in the other internal iliac artery 1i, 1d.

Each wire constituting the mesh of the sleeves 3 and 4 has a surface condition suitable for ensuring sufficient anchoring either inside each tube 2a, or inside each artery.

It goes without saying that the tubes 2a of the stent 2 can cross without influencing the method of fixing said stent.

It should moreover be understood that the above description has been given only by way of example and that it in no way limits the field of the invention from which one would not depart by replacing the execution details described by all other equivalents.

Claims

1. Aortoiliac stent for the treatment of aneurysms of the abdominal aorta, comprising two tubes (2a) capable of deforming elastically in all directions and each end of which (2b, 2c) is integral with a mesh sleeve (3, 4), characterized in that said tubes are of conical profile so that their upper ends (2b) are of a larger diameter than that of their lower ends (2c), while said sleeves are provided with hooking means ( 5) for retaining the endoprosthesis and are made of a biocompatible, deformable metallic material with shape memory.

2. Aortoiliac endoprosthesis according to claim 1, characterized in that said ends (2b) of larger diameter of said conical profile tubes are joined against each other by deformation of said mesh sleeves (3) so that the outer periphery of each tube (2a), on the one hand, perfectly matches the inner wall of the abdominal aorta (1) and, on the other hand, is pressed against your outer periphery of the other tube to ensure perfect sealing of the stent (2).

3. Aortoiliac endoprosthesis according to claim 1, characterized in that the upper ends (2b) of each tube (2a) completely cover the corresponding sleeves (3) allowing only the hooks (5) to retain the stent (2) in the inner wall of the abdominal aorta (1).

4. Aortoiliac stent according to claim 1, characterized in that the upper ends (2b) of each tube (2a) only partially cover the sleeves (3) so that the hooks (5) are fixed in the wall internal abdominal aorta (1) above the renal arteries (1d and 1e) to allow the passage of blood flow.

5. Aorto-iliac endoprosthesis according to claim 1, characterized in that the lower ends (2c) of each tube (2a) completely cover the corresponding sleeves (4) allowing only the hooks (5) to retain the stent (2) in the inner wall of the primary iliac artery (1a, 1b).

6. Aortoiliac stent according to claim 1, characterized in that the lower ends (2c) of each tube (2a) only partially cover the sleeves (4) so that the hooks (5) are fixed in the internal wall of the external iliac artery (1g, 1h) to allow the passage of blood flow in the internal iliac artery (1i, 1d).

7. Aorto-iliac endoprosthesis according to claim 1, characterized in that the wire constituting the mesh of the sleeves (3, 4) has a surface condition suitable for ensuring sufficient anchoring either inside each tube (2a), either inside each artery.