Insertion System for Implants for Treatment of Bifurcation Aneurysms

Abstract

The invention relates to an insertion system for an implant (1) for influencing the blood flow in the region of aneurysms (22) located at vascular bifurcations. The implant (1) has two distal tubular implant portions (2) which are intended to be placed in blood vessels (21) branching off from the stem blood vessel (20) and which are connected to one another at a branching point (4). The insertion system has two sleeves (5) which are each designed to hold a distal tubular implant portion (2). The two sleeves (5) each have a distal sleeve portion (6) and the distal sleeve portions (6) each have an opening zone (7) extending in the longitudinal direction. The distal sleeve portions (6) are each adjoined proximally by a proximal portion (8), by means of which the sleeves (5) can be retracted in the proximal direction so that the opening zones (7) open and the distal tubular implant portions (2) each pass through the opening zones (7) and are released into the branching blood vessels (21). Alternatively, it is also possible to use an individual sleeve which has an opening zone for gradual release of the implant (1) or an insertion system with the implant (1) releasably attached to the outside.

Claims

1. An insertion system for an implant (1) for influencing the flow of blood in the region of aneurysms (22) located at vessel branches, with the implant (1) having two distal tubular implant sections (2) which are intended to be placed in blood vessels (21) branching off from the parent blood vessel (20) and which are connected to one another at a branching point (4), wherein the insertion system is provided with two sleeves (5), each configured to accommodate a distal tubular implant section (2), wherein the two sleeves (5) each being provided with a distal sleeve section (6) and the distal sleeve sections (6) each having a longitudinally extending opening zone (7), wherein proximally adjoining each of the distal sleeve sections (6) there is a proximal section (8) via which the sleeves (5) can be withdrawn in the proximal direction so that the opening zones (7) open and each of the distal tubular implant sections (2) passes through the opening zones (7) and are released in the branching blood vessels (21).

2. An insertion system according to claim 1, wherein the opening zones (7) are provided in the form of longitudinal slots.

3. An insertion system according to claim 1, wherein the sleeves (5), at least in the region of the distal sleeve sections (6), are composed of a flexible tube material.

4. An insertion system according to claim 1, wherein the proximal sections (8) are designed to be sleeve-shaped or tubular.

5. An insertion system according to claim 1, wherein the proximal sections (8) are designed to be in the form of wires, filaments or strips.

6. An insertion system according to claim 1, wherein, the insertion system comprises a trunk sleeve (9) provided for accommodating a tubular trunk section (3) of the implant (1), the trunk sleeve (9) being withdrawable in proximal direction for releasing the trunk section (3).

7. An insertion system according to claim 6, wherein the trunk sleeve (9) is made of a flexible tube material.

8. An insertion system for an implant (1) for influencing the flow of blood in the region of aneurysms (22) located at vessel branches, wherein said implant (1) comprising two distal tubular implant sections (2) which are intended to be placed in blood vessels (21) branching off from the parent blood vessel (20) and which are connected to each other at a branching point (4), wherein the insertion system being provided with a sleeve (11) having two distal sleeve arms (12) which are each configured to accommodate a distal tubular implant section (2) and which are interconnected, the sleeve (11) having a continuous opening zone (14, 15) in the distal direction and with the sleeve (11) having a proximal section (13) via which the sleeve (11) can be retracted in the proximal direction so that the opening zone (14, 15) opens and each of the distal tubular implant sections (2) pass through the opening zone (14, 15) and are released in the branching blood vessels (21), wherein the opening zone (14, 15) is designed such that the sleeve (11) opens sequentially from the distal ends of the distal sleeve arms (12) in the proximal direction when the implant (1) is released.

9. An insertion system according to claim 8, wherein the opening zone (14, 15) comprises a continuous slot (14) pointing in the distal direction, wherein the edges of the slot (14) at least partially overlap in such a way that the overlap increases from distal to proximal.

10. An insertion system according to claim 8, wherein the opening zone (14, 15) comprises a weakening zone facing in the distal direction, with said weakening zone being designed such that the force required for opening increases from distal to proximal.

11. An insertion system according to claim 10, wherein the weakening zone is a perforation (15).

12. An insertion system according to claim 8, wherein the proximal section (13) is a proximal sleeve arm provided for accommodating a tubular trunk section (3) of the implant (1).

13-27. (canceled)

Description

[0099] Clarification of the invention is provided by the following figures where

[0100] FIG. 1 shows a Y-shaped implant with two distal and one proximal tubular implant section;

[0101] FIG. 2 shows another Y-shaped implant with two distal and one proximal tubular implant section;

[0102] FIG. 3 illustrates an implant having two distal tubular implant sections without a proximal implant section;

[0103] FIG. 4 shows an inventive insertion system according to a first embodiment;

[0104] FIG. 5 shows an inventive insertion system according to a second embodiment;

[0105] FIG. 6 is another variant of the second embodiment of the insertion system;

[0106] FIG. 7a illustrates an inventive insertion system according to a third embodiment;

[0107] FIG. 7b is a sectional view of the insertion system shown in FIG. 7a;

[0108] FIG. 8 shows the insertion system according to FIG. 7a,b with the implant placed in front of an aneurysm;

[0109] FIG. 9 is a sectional view of the insertion system with implant placed according to FIG. 8 and

[0110] FIG. 10 is another variant of the third embodiment of the insertion system.

[0111] FIG. 1 shows an implant 1, i.e. a bifurcation flow diverter, as it can be introduced into the vascular system and placed in front of a bifurcation aneurysm with the aid of the insertion system proposed by the present invention. Implant 1 has three tubular implant sections 2, 3, of which the two distal implant sections 2 are positioned in the branching blood vessels, whereas the proximal trunk section 3 is anchored in the parent blood vessel. The aneurysm is located distal to branch point 4 between the two distal implant sections 2. Blood flow from the parent blood vessel into the two branching blood vessels has been indicated by arrows.

[0112] The implant 1 illustrated here is essentially a round braiding that merges from the proximal trunk section 3 into one of the two distal implant sections 2, with an additional branching arm being attached as an additional distal implant section 2. It is, of course, mandatory that the configuration of the connection between the individual implant sections 2, 3 makes sure the flow of blood also takes place into the second, attached distal implant section 2. Moreover, there should be good coverage of the aneurysm by a tight braid of the wires or struts used.

[0113] FIG. 2 shows an implant 1 which is essentially similar to the implant depicted in FIG. 1, but in this case a continuous tubular structure has been provided for the two branching blood vessels and a lateral branch has been attached as proximal trunk section 3. Here too, of course, the passage of the flow of blood from the parent blood vessel into the two branching blood vessels must be ensured in the direction indicated by the arrows. A certain advantage over the variant shown in FIG. 1 can be seen in the fact that in the area distal to the branching point 4 no seams or irregular mesh or braid densities are to be expected, which could under some circumstances cause too high a permeability in the direction of the aneurysm.

[0114] FIG. 3 is the representation of another implant 1 that does not have a proximal trunk section, but consists only of two distal implant sections 2. In this case as well, it is also mandatory that the aneurysm is covered distal to the branch point 4; and, additionally, the flow of blood from the parent blood vessel into the two distal implant sections 2 must be ensured, which is why an opening is arranged in the implant structure in the proximal direction through which blood can flow as symbolized by the arrows.

[0115] FIG. 4 shows a first embodiment of the insertion system according to the invention together with the implant 1 to be placed in position. The insertion system is provided with two sleeves 5, the distal sleeve sections 6 of which accommodate the distal implant sections 2. In the proximal direction, proximal sections 8 respectively join the distal sleeve sections 6 so that the sleeves 5 can be retracted as a whole in the proximal direction to release the implant 1. The proximal sections 8 can also be designed to be sleeve-shaped or tubular. A third sleeve is provided as a trunk sleeve 9 and surrounds the proximal trunk section 3 of the implant 1. The trunk sleeve 9 can also be retracted in the proximal direction for the purpose of releasing the proximal trunk section 3.

[0116] In order to allow the implant 1 and the distal implant sections 2 to emerge from the distal sleeve sections 6, these are provided with opening zones 7. These are arranged in the form of longitudinal slots that run along the sleeves 5 over a certain area in the longitudinal direction. In this case, the opening zones 7 extend from the distal end of the distal sleeve sections 6 in the proximal direction to such an extent that the distal implant sections 2 can pass through completely when the sleeves 5 are withdrawn in the proximal direction. Proximal to the opening zones 7, on the other hand, the sleeves 5 can essentially be designed as a simple sleeve or tube, since the passage of the implant 1 is no longer an issue in this area.

[0117] The insertion system can be brought to the intended position by a microcatheter 10. As soon as this position is reached, the microcatheter 10 can initially be retracted at least far enough in the proximal direction to expose the insertion system with the implant 1 inside. Following this, the sleeves 5 can be retracted simultaneously or one after the other in proximal direction to release the two distal implant sections 2, whereupon they expand and come in contact with the inner vessel wall of the branching blood vessels. As a rule, the proximal implant section 3 is released last by withdrawing the trunk sleeve 9 of the insertion system in the proximal direction.

[0118] In FIG. 5 a first variant of an insertion system is depicted according to the second embodiment, with the implant not shown. The insertion system is provided with a sleeve 11 that has two distal sleeve arms 12. The distal sleeve arms 12 are intended to accommodate the distal implant sections 2. Connected to the two distal sleeve arms 12 is the proximal sleeve arm 13, in which the proximal trunk section 3 of the implant is positioned.

[0119] The two distal sleeve arms 12 are provided with a slot 14 extending from the distal end of the first distal sleeve arm 12 to the distal end of the second distal sleeve arm 12. The slot 14 is configured such that the edges along the slot 14 do not overlap at the distal ends of the distal sleeve arms 12, with an overlap of the slot edges existing however in the area where the proximal sleeve arm 13 branches into the two distal sleeve arms 12. The effect of this is that when sleeve 11 is withdrawn, the implant initially emerges from the slot 14 at the distal end of the distal implant sections 2 and begins to expand, whereas the regions of the implant 1 located farther proximal only emerge from the sleeve 11 a little bit later. Accordingly, the distally located areas of implant 1 adapt to the inner wall of the blood vessel first and only at a slightly later time do the more proximally located areas contact the wall, which is advantageous with regard to a controlled release of implant 1.

[0120] FIG. 6 shows an insertion system which is essentially identical to that indicated in FIG. 5, but in this case the opening zone is not provided in the form of a slot 14, but in the form of a perforation 15. The size of the openings arranged in the perforation 15 in this case increases from proximal to distal, i.e. in the region of the branching between the two sleeve arms 12 the size of the openings is relatively small, whereas at the distal ends of the distal sleeve arms 12 it is significantly larger. The perforation 15 thus tears open first at the distal end of the distal sleeve arms 12 when the sleeve 11 is withdrawn in the proximal direction, so that in this location as well the implant emerges from the sleeve 11 first and can then expand. Only slightly later is the implant also released further proximally, which is due to the fact that tearing open the perforation 15 requires more force to be applied here. Therefore, the implant is released gradually from distal to proximal.

[0121] In FIG. 7a the insertion system according to a third embodiment is shown in which the implant to be inserted is arranged on the outside. The implant itself is not shown here. This is a Y-shaped inner shaft system that has a proximal shaft section 17 branching into two distal shaft sections 16. The insertion system is brought to the intended position with the aid of two guidewires 18, one of the guidewires 18 being inserted into the first branching blood vessel and the other guidewire 18 being inserted into the second branching blood vessel in order to be able to subsequently move the insertion system to the desired position via the guidewires 18, with the two distal shaft sections 16 being guided at the same time into the respective branching blood vessels.

[0122] FIG. 7b is a sectional view of the insertion system shown in FIG. 7a, i.e. it can be seen how guidewires 18 first extend in parallel through the proximal shaft section 17 and then branch into the two distal shaft sections 16.

[0123] In FIG. 8 the system from FIG. 7 is illustrated with implant 1 applied in the blood vessel system. The insertion system was placed in front of an aneurysm 22, with the two distal shaft sections 16 being placed in the branching blood vessels 21 and the proximal shaft section 17 being placed in the parent blood vessel 20. Implant 1 again features two distal implant sections 2 and the proximal trunk section of the implant 3. At the two distal ends of the distal implant sections 2, the implant 1 is connected to the distal shaft sections 16 by means of fixation points 19. The fixation points 19 may be, for example, chemically or electrolytically dissolvable connecting points, i.e., detachment of the implant 1 from the distal shaft sections 16 causes the implant 1 to expand and be released from the shaft sections. The shaft sections 16, 17 forming part of the insertion system can subsequently be withdrawn in a proximal direction while the implant 1 remains in the desired position in the blood vessel system in front of the aneurysm neck.

[0124] The insertion system including implant 1 is brought to the desired position by a microcatheter 10. Release of the implant 1 in the region of the proximal implant trunk section 3 typically occurs by retraction of the microcatheter 10 in the proximal direction.

[0125] FIG. 9 shows the insertion system with implant 1 of FIG. 8 in sectional view; it can be seen how the guidewires 18 pass through the interior of the trunk sections 16, 17, while the distal implant sections 2 are arranged on the two distal trunk sections 16 and the proximal implant trunk section 3 is seated on the proximal trunk section 17.

[0126] Finally, FIG. 10 shows an alternative form for securing the distal implant sections 2 to the insertion system, with the distal shaft sections having largely been omitted here. Caps 23 are placed over the distal ends of each of the distal implant sections 2 to prevent the distal implant sections 2 from expanding while the caps 23 are in position on the distal implant sections 2. To enable the caps to be removed from the implant sections 2, push wires 24 are advanced in the distal direction. The push wires 24 extend through small openings at the distal ends of the caps 23 and are provided with thickenings 25, so that as the push wires 24 are advanced distally, the thickenings 25 located further proximally will move the caps 23 forward and in this way remove them from the implant sections 2. The farther distally located thickenings 25 are provided to prevent the push wires 24 from becoming disconnected from the caps 23. Moreover, radiopaque markers 26 are provided on the proximal shaft section 17 to allow the implantation process to be visualized.