Double stent

Abstract

The invention relates to a double stent comprising coaxially arranged stents, wherein a first membrane (4) being arranged between a first inner stent (2) and at least two outer stents (3), and a second membrane (5) being arranged on the outer stents (3), with the membrane ends of the first (4) and second membrane (5) being brought together at the ends of the stents (2, 3) and folded around to the inside of the first stent (2) and clamped securely under flexible tongues (6) of the first stent (2).

Claims

1. A double stent comprising coaxially arranged stents, wherein a first membrane is arranged between a first inner stent and at least two outer stents, wherein a second membrane is arranged on the at least two outer stents and wherein the membrane ends of the first membrane and the second membrane are brought together at the ends of the first inner stent and the at least two outer stents and are folded over onto the inside of the first inner stent and clamped securely under flexible tongues of the first inner stent.

2. The double stent according to claim 1, wherein at least one of the first inner stent and the at least two outer stents has a mesh structure.

3. The double stent according to claim 1, wherein at least the first inner stent is provided with a plurality of ring segments arranged side by side and having a meandering structure which are connected to one another by means of webs.

4. The double stent according to claim 3, wherein the flexible tongues are provided at connecting webs between adjacently arranged ring segments of the first inner stent (2).

5. The double stent according to claim 4, wherein the flexible tongues are cut into the connecting webs.

6. The double stent according to claim 1, wherein the flexible tongues point to the outside of the first inner stent.

7. The double stent according to claim 1, wherein the flexible tongues are arranged in the peripheral end regions of the first inner stent.

8. The double stent according to claim 1, wherein the at least two outer stents are arranged at the ends of the double stent.

9. The double stent according to claim 1, wherein the at least two outer stents are flexibly connected with each other.

10. The double stent according to claim 9, wherein the first membrane and/or the second membrane comprises ePTFE.

11. The double stent according to claim 1, wherein each of the at least two outer stents has a structure that is denser than that of the first inner stent.

12. The double stent according to claim 1, wherein each of the first inner stent and the at least two outer stents have webs arranged with gaps between the webs.

13. The double stent according to claim 1, wherein the first membrane and/or the second membrane comprises plastic material.

Description

(1) Further elucidation of the invention is provided through the enclosed figures showing preferred embodiments of the invention. It goes without saying that the characteristics shown in the figures shall in each case be regarded individually as being part of the invention and should not be understood exclusively in the context of the other characteristics illustrated in the figures, where

(2) FIG. 1 is a schematic representation of a stent in accordance with the invention;

(3) FIG. 2 shows a variant of the clamping principle used for the membranes; and

(4) FIG. 3 illustrates a section through the wall of a stent proposed by the invention.

(5) The double stent 1 shown in FIG. 1 comprises a first inner stent 2 and a second outer stent 3 that are arranged coaxially to each other. The outer stent 3 is slightly shorter than the inner stent 2. The double stent is shown in the non-expanded state. Between the inner stent 2 and the outer stent 3 a first inner membrane 4 is provided and on the outer stent 3 a second outer membrane 5 is arranged, with both membranes being made of ePTFE.

(6) The inner membrane 4 and the outer membrane 5 are brought together at their ends and folded inwards into the cavity of the inner stent 2 around the edge of the two stents. Schematically shown in the figure is one of several flexible tongues 6, which is bent inwards and under which the membrane ends protrude. For the purpose of fixing the membrane ends, the flexible tongues 6 are bent back outwards resulting in the membrane ends being clamped underneath them.

(7) In FIG. 2 a stent design is illustrated for the inner stent 2, said design providing for two closely to the periphery adjacently arranged ring segments 8 to be joined together by means of connecting webs 7. Flexible tongues 6, which are movable with respect to the stent plane, are cut into the connecting webs 7.

(8) With a view to increasing the contact area for the tubular film (not shown), the flexible tongues 7 are of angled configuration in the free end area which improves the clamping effect in relation to the inserted membrane.

(9) FIG. 3 illustrates the principle of the double stent proposed by the invention comprising a single inner stent 2, two terminally located stents 3 and stent 3 in the middle position, as well as the intermediate membrane 4 and the covering membrane 5, both folded around inwards.