WO2022256924A1

WO2022256924A1 - Stent for bifurcated vessel

Info

Publication number: WO2022256924A1
Application number: PCT/CA2022/050912
Authority: WO
Inventors: Ahmed Bentridi
Original assignee: Ahmed Bentridi
Priority date: 2021-06-08
Filing date: 2022-06-08
Publication date: 2022-12-15
Also published as: CA3219718A1

Abstract

A stent for use with occluded bifurcated vessels. The stent includes two elongate conduits both with a mesh sidewall and angled ends. A connector connects the angled ends so that they face each other to form a V-shaped gap. The connector is hingeably deformable so that the conduits are angled towards each other for location near a junction between the bifurcated vessels. This locates conduits in each of the bifurcated vessels.

Description

STENT FOR BIFURCATED VESSEL

TECHNICAL FIELD

The present generally concerns stents, and more specifically for a stent for use in narrowed vascular bifurcation.

BACKGROUND

Anatomic vessels have lumens in which a stenosis can form causing partial or complete occlusion. Stents are well-known and widely used in interventional radiology and cardiology to maintain the vessel open. Two designs are currently available, namely self expandible and balloon expandible stents. Both stent designs have metallic mesh shaped structures, which when deployed in the vessel through minimally invasive vascular access, form scaffolding to avoid the recoil of the vessel wall so as to keep the vessel open. The mesh includes different, large cells which give the self-expanding stent more flexibility with less radial force, whereas the balloon expandible stent is equipped with small cell structure which are less flexible but have greater radial force. These are reserved for use in known highly calcified stenosis in straight vessels.

Bifurcated vessels present unique technical problems, largely because of their Y-shape. Kissing stents are known and used to open bifurcated vessels. They typically consist of two separate stents which when located beyond the bifurcated vessel junction are clipped together and then individually expanded. The upper region of both stents contact each other but are not contiguous. This requires considerable interventional endovascular skill to insert the kissing stent. Kissing stents have been reported to fail due to unclipping of the two stents in situ. Bifurcated stents, on the other hand, are pre-formed Y-shaped stents that are reserved for patients with aorto-iliac aneurysm. These are high cost and require large vascular access. This type of surgery presents many additional problems to the patient including infection and long recovery time. Another technique can be used specially in coronaries. Crush stenting consists of two crossing stents, which are delivered through the bifurcation after crushing and remodeling the two stent using balloon. Disadvantageously, this too requires high technicality and is time consuming. Thus, there is a clear unmet medical need for an improved stent for use in occluded bifurcated vessels.

BRIEF SUMMARY

I have significantly reduced, or essentially eliminated, the problems associated with the designs described above by designing an endovascular and biliary prosthetic stent that reproduces the anatomy of bifurcation. Advantageously, the stent is useful for single access endovascular delivery and is applicable for all types of bifurcations such as arterial, venous and biliary bifurcation. The stent is designed to reproduce the anatomy of a bifurcated vessel and when inserted provides significantly reduced flow resistance. The novel and unobvious stent uses a central open cell concept which permits location of two mesh walled conduits in the two vessels of the bifurcated vessel This design might be useful in coronary and bronchic bifurcation.

Accordingly, in one embodiment there is provided a stent for use with occluded bifurcated vessels, the stent comprising: a first elongate conduit having a first mesh sidewall and a first angled end; a second elongate conduit having a second mesh sidewall and a second angled end; and a connector member for connecting the first and second angled ends so that they face each other to form a V-shaped gap, the connector member being hingeably deformable so that the first and second conduits are angled towards each other for location near a junction between the bifurcated vessels so as to locate the first and second elongate conduits in each of the bifurcated vessels.

In one example, the connector member is an open cell located at a junction between the first and second angled ends. In another example, the first elongate conduit has a first longitudinal axis; and the second elongate conduit has a second longitudinal axis. In a default configuration, the first and second longitudinal axes are disposed co-linear. The default configuration permits entry of the first and second conduits into a main vessel located away from the junction between the bifurcated vessels. In an operable configuration, the first and second conduits are hingeably deformed so as to locate the first and second elongate conduits in each of the bifurcated vessels, the first and second longitudinal axes being disposed co-linear with the bifurcated vessel.

In one example, one of the vessels has a stenosis.

In one example, both of the vessels have a stenosis.

In one example, the bifurcated vessel is arterial.

In one example, the bifurcated vessel is venous.

Accordingly, in another embodiment, there is provided a method of inserting a stent into a bifurcated vessel having at least one stenosis, the method comprising: locating one end of the stent into a main vessel away from a junction of a bifurcated vessel, the stent having a first elongate conduit having a first mesh sidewall and a first angled end, a second elongate conduit having a second mesh sidewall and a second angled end; and a connector member for connecting the first and second angled ends so that they face each other to form a V-shaped gap; hingeably deforming the stent about the V-shaped gap so that the first and second conduits are angled towards each other; and locating the first and second conduits in each of the bifurcated vessels so that the connector member is located near a junction between the bifurcated vessels.

Accordingly, in another embodiment, there is provided a method of treating a subject having at least one stenosis in a bifurcated vessel, the method comprising: locating one end of the stent into a main vessel away from a junction of a bifurcated vessel, the stent having a first elongate conduit having a first mesh sidewall and a first angled end, a second elongate conduit having a second mesh sidewall and a second angled end; and a connector member for connecting the first and second angled ends so that they face each other to form a V-shaped gap; hingeably deforming the stent about the V-shaped gap so that the first and second conduits are angled towards each other; and locating the first and second conduits in each of the bifurcated vessels so that the connector member is located near a junction between the bifurcated vessels.

In one example, the subject is a mammal.

In one example, the subject is a human

In one example, one of the vessels has a stenosis.

In one example, both of the vessels have a stenosis.

In one example, the bifurcated vessel is arterial.

In one example, the bifurcated vessel is venous.

In one example, the bifurcated vessel is biliary.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of that described herein will become more apparent from the following description in which reference is made to the appended drawings wherein:

Fig. l is a diagrammatic representation of a bifurcated vessel showing stenosis;

Fig. 2 is a diagrammatic representation of a V-shaped stent located in a partially occluded bifurcated vessel

Fig. 3 is a diagrammatic representation of a diagram of a stent in a default configuration for insertion into a main vessel; and

Fig. 4 is a diagrammatic representation of the stent delivered to a bifurcated vessel.

DETAILED DESCRIPTION

Definitions

Unless otherwise specified, the following definitions apply: The singular forms “a”, “an” and “the” include corresponding plural references unless the context clearly dictates otherwise.

As used herein, the term “comprising” is intended to mean that the list of elements following the word “comprising” are required or mandatory but that other elements are optional and may or may not be present.

As used herein, the term “consisting of” is intended to mean including and limited to whatever follows the phrase “consisting of”. Thus, the phrase “consisting of’ indicates that the listed elements are required or mandatory and that no other elements maybe present.

As used herein, the term "subject" is intended to mean humans and non-human mammals such as primates, cats, dogs, swine, cattle, sheep, goats, horses, rabbits, rats, mice and the like.

As used herein, the term "treating" or "treatment" is intended to mean treatment of a disease-state associated with at least one stenosis a bifurcated vessel.

Referring to FIGs. l and 2, there is shown generally at to a prosthetic stent for surgical use in mammalian subjects having occluded bifurcated vessels 12. In the examples shown, the mammalian subject is a human subject. In the example shown, the bifurcated vessel 12 is an iliac bifurcation located in communication with an aorta 14. The bifurcated vessel 12 includes two vessel 16, 18, which in this example have a stenosis 19. The bifurcated vessels 12 that are amenable to the stent 10 include, but are not limited to, arterial vessels, venous vessels and biliary vessel. The stent 10 may be used to treat the human subject in which one of the vessels has a stenosis or both of the vessels have a stenosis.

Referring now to Figs. 3 and 4, the stent 10 includes a first elongate conduit 22 which has a first mesh sidewall 24 and a first angled end 26. and a second elongate conduit 28 having a second mesh sidewall 30 and a second angled end 32. In the example shown, the stent is made from Nitinol alloy with the first and second angled ends 26, 32 being cut to a range of between about 30 to 45 degrees. An open cell connector member 34 connects the first and second angled ends 26, 32 together so that they face each other to form a V-shaped gap 36. As best seen in Figs. 2 and 4, the connector member 34 is hingeably deformable about a hinged junction 38 so that the first and second conduits 22, 28 are angled towards each other, By hingeably deforming (or bending) the conduits 22, 28 about the hinged junction 38, the V-shaped gap 36 widens and permits the stent 10 to be located near a junction 40 between the bifurcated vessels 16, 18 so as to locate the first and second elongate conduits 22, 28 in each of the bifurcated vessels 16, 18.

As best seen in Figs. 3 and 4, the first elongate conduit 22 has a first longitudinal axis 42 and the second elongate conduit 28 has a second longitudinal axis 44. In a default configuration, as shown in Fig. 3, the first and second longitudinal axes 42, 44 are disposed co-linear. The stent 10 when in the default configuration permits entry of the first and second conduits 22, 28 into a main vessel located away from the junction 40 between the bifurcated vessels 16, 18. In an operable configuration, the first and second conduits 22, 28 are hingeably deformed so as to locate the first and second elongate conduits 22, 28 in each of the bifurcated vessels 16, 18 so that he first and second longitudinal axes 42, 44 are disposed co-linear with the bifurcated vessel to permit expansion and retention in the vessels. Advantageously, the stent 10 is a one- piece, modular system which permits accurate surgical placement with minimal invasion and time spent in the operating theater.

Referring specifically to Fig 3, a closed cell is located opposed to the open cell. In the closed cell structure, the mesh structure is formed by several cells. The closed cell feature of the first and second mesh sidewalls has cell geometry which connects consistently throughout to form complete and bridging “diamond-shaped” cells that are welded together at each cell junction. The central open cell, on the other hand, is attached to adjacent cells at only one or two edge to make the stent more flexible. Other Embodiments

From the foregoing description, it will be apparent to one of ordinary skill in the art that variations and modifications may be made to the embodiments described herein to adapt it to various usages and conditions.

Claims

What Is Claimed Is:

1. A stent for use with occluded bifurcated vessels, the stent comprising: a first elongate conduit having a first mesh sidewall and a first angled end; a second elongate conduit having a second mesh sidewall and a second angled end; and a connector member for connecting the first and second angled ends so that they face each other to form a V-shaped gap, the connector member being hingeably deformable so that the first and second conduits are angled towards each other for location near a junction between the bifurcated vessels so as to locate the first and second elongate conduits in each of the bifurcated vessels.

2. The stent, according to claim l, in which the connector member is an open cell located at a junction between the first and second angled ends.

3. The stent, according to claim l, in which the first elongate conduit has a first longitudinal axis; and the second elongate conduit has a second longitudinal axis.

4. The stent, according to claim 3, in which in a default configuration, the first and second longitudinal axes are disposed co-linear.

5. The stent, according to claim 4, in which the default configuration permits entry of the first and second conduits into a main vessel located away from the junction between the bifurcated vessels.

6. The stent, according to claim 3, in which in an operable configuration, the first and second conduits are hingeably deformed so as to locate the first and second elongate conduits in each of the bifurcated vessels, the first and second longitudinal axes being disposed co-linear with the bifurcated vessel.

7. The stent, according to claim 1, in which one of the vessels has a stenosis.

8. The stent, according to claim l, in which both of the vessels have a stenosis.

9. The stent, according to claim l, in which the bifurcated vessel is arterial to. The stent, according to claim l, in which the bifurcated vessel is venous n. The stent, according to claim l, in which the bifurcated vessel is biliary.

12. A method of inserting a stent into a bifurcated vessel having at least one stenosis, the method comprising: locating one end of the stent into a main vessel away from a junction of a bifurcated vessel, the stent having a first elongate conduit having a first mesh sidewall and a first angled end, a second elongate conduit having a second mesh sidewall and a second angled end; and a connector member for connecting the first and second angled ends so that they face each other to form a V-shaped gap; hingeably deforming the stent about the V-shaped gap so that the first and second conduits are angled towards each other; and locating the first and second conduits in each of the bifurcated vessels so that the connector member is located near a junction between the bifurcated vessels.

13. A method of treating a subject having at least one stenosis in a bifurcated vessel, the method comprising: locating one end of the stent into a main vessel away from a junction of a bifurcated vessel, the stent having a first elongate conduit having a first mesh sidewall and a first angled end, a second elongate conduit having a second mesh sidewall and a second angled end; and a connector member for connecting the first and second angled ends so that they face each other to form a V-shaped gap; hingeably deforming the stent about the V-shaped gap so that the first and second conduits are angled towards each other; and locating the first and second conduits in each of the bifurcated vessels so that the connector member is located near a junction between the bifurcated vessels.

14. The method, according to claim 13, in which the subject is a mammal.

15. The method, according to claim 13, in which the subject is a human

16. The method, according to claim 13, in which one of the vessels has a stenosis.

17. The method, according to claim 13, in which both of the vessels have a stenosis. 18. The method, according to claim 13, in which the bifurcated vessel is arterial

19. The method, according to claim 13, in which the bifurcated vessel is venous.

20. The method, according to claim 13, in which the bifurcated vessel is biliary.