WO2007134587A2

WO2007134587A2 - Stent for interventional applications, in particular for treatment of varicose veins and for treatment of chronic venous insufficiency (cvi)

Info

Publication number: WO2007134587A2
Application number: PCT/DE2007/000918
Authority: WO
Inventors: Stefan Von Sommoggy
Original assignee: Stefan Von Sommoggy
Priority date: 2006-05-22
Filing date: 2007-05-19
Publication date: 2007-11-29
Also published as: DE102006025253A1; WO2007134587A3

Abstract

Stent for interventional applications, in particular for treatment of varicose veins and for treatment of chronic venous insufficiency, characterized by a stent body and by a plurality of spontaneously spreading fingers which are made of a resiliently elastic material and which, in a splayed or opened state of release, have their free ends protruding clearly beyond the outer face or outer contour of the stent body.

Description

Stent, for interventional applications, in particular for the treatment of varicosis and for the treatment of chronic venous insufficiency (CVI)

The invention relates to a stent according to the preamble of claim 1 or 1 first

Known are u.a. Interventional occlusion methods in the arterial vascular system by inserting coils into smaller vessels or by inserting occluder stents. However, these methods are not suitable in the venous area because of the risk of washing off the coils or occlusive stents.

From US 2005/0154444 A1, for example, a stent with an opening is known, to which at least one further stent can be connected to produce a fluid-tight connection between two arterial blood vessels. For liquid-tight connection of two such tubular stents, a ring-like connecting element is provided, which has outwardly projecting elastic fingers with spherical ends.

WO 02/091952 A2 shows an annular connecting element for "fluid-tight" connection of two blood vessels, which is designed in the manner of a wire frame. Occasionally, the free ends of the annular connecting element are hereby designed inter alia for piercing the vessel walls.

Furthermore, from DE 197 03 482 A1 discloses a stent formed from at least two opposing coils, which are made of a wire-shaped material. WO 00/27303 also describes a helical stent made from a wire-shaped material. The object of the invention is to show a stent, which is also suitable in particular for interventional applications in venous vascular systems, especially for the interventional treatment of varicosis and / or the treatment of chronic venous insufficiency (CVI).

To solve this problem, a stent according to claim 1 or 1 1 is formed. Further developments of the invention are the subject of the dependent claims.

The advantages of the stent according to the invention are that for the placement of the stent the usual, and in particular also of treatment methods in the arterial vascular system known and existing aids are used. Further advantages of the stents according to the invention or of the methods possible with these are:

> No high initial costs

> Possibility of treatment of all forms of varices

> One Step Therapy

> Local anesthesia (also short-stretched)

> Permanent therapy

> Short intervention time

> No long development and testing time

> No side effects

> Acceptable one-time system price / intervention

> No compression

> Immediate work ability

> Outpatient procedure

The invention will be explained in more detail below with reference to the figures, each of which, in a simplified representation, shows a vein together with various embodiments of the stent according to the invention. The stent, generally designated 1 in FIG. 1, consists essentially of a cylindrical stent body 2 arranged in the illustrated embodiment with a continuous bore 3, ie open at both ends, as well as with a plurality of thin wire-shaped fingers 4, respectively are attached at one end to a front side of the stand body 2 and protrude beyond this end face.

The wire-shaped fingers 4 are made of a permanently elastic material, such as spring steel or other vascular compatible permanently elastic material and are biased so that they fanned in the released or open state, as shown in FIG. 1 at the position A.

For varicose treatment, the stents 1 are placed in a vein 5 by suitable means, e.g. Discarded at junctions of larger venous branches, in the folded or closed state corresponding to the position B of Fig. 1, in which the individual fingers 4 deformed against their inherent elasticity are also adjacent with their free ends of the axis STA of the stent body 2. After release of the stents, the fingers 3 stretch, pierce with their free ends the vein wall and thus cause a reliable anchoring of the respective stent 1 in the vein 5 against flooding. As a result, a secure closure and a clear reduction in lumen can be achieved.

Fig. 2 shows a schematic representation of another possible embodiment of the invention, a stent 1 a, which differs from the stent 1 essentially only in that the serving for anchoring in the vein 5 fingers 4 provided only at one end face of the stent body 2 are. The introduction of the stent 1 a is also in this embodiment, in turn, so that the first when folded fingers (position B of FIG. 2) after the fan-like Spreading (position A) with their free ends again pierce the vein wall and thread on the vein 5 and are thus anchored against flushing, whereby by threading the vein on the spread fingers 4 also enters a narrowing of the lumen cross-section.

FIG. 3 shows, as a further embodiment, a stent 1 b, which differs from the stent 1 in that instead of the fingers 4 projecting away from the end faces of the stent body 2, fingers 6 are provided, which in turn consist of a thin, wire-like, spring-elastic material, for example Spring steel exist and extend in the open state (position A) spirally away from the peripheral surface of the stent body 2 away.

In the folded state, the fingers 6 are tight against the peripheral surface of the stent body 2 (position B). After unfolding the fingers 6, these are introduced by rotating the stent 1 b about the axis STA with their free ends in the vein wall piercing them, namely for anchoring the stent I b and for reducing the lumen cross-section.

4 shows a stent 1 c, which consists of the stent body 2 and a single helically or helically shaped arm or finger 7, which in the closed state (position B) tightly surrounds the stent body 2 and in the open state (position A). protrudes with a widened helix diameter over an end face of the stent body 2. The arm or finger 7 is in turn resiliently made of a wire-shaped material, such as spring steel.

Specifically with the stent 1 c, a defined lumen width can be ensured there after release in a vein 5, without the flow through a vein 5 being blocked. As a result, a treatment of chronic venous insufficiency is possible. So can with flap defects also in the deep Reduces venous system by reducing the venous lumen of the reflux significantly and deliberately reduced and this may be the flap function restored.

Especially with the stents 1 b and 1 c, it is possible to form the spiral-like arms 6 or 7 so that they are screwed in the unfolded state when fixing the stent 1 b or 1 c approximately tangentially or in the longitudinal direction in the vessel wall and thereby the endothelium of the vessel wall (vessel wall inner layer) remains at least largely intact.

The placement of the stents 1, 1 a, 1 b and 1 c follows e.g. basically by puncturing the saphenous vein at the ankle in local anesthesia, inserting a guidewire and threading the vein 5. The therapy catheter 8 (flexible tube catheter) is then placed over the guide wire. Thereafter, the guidewire is replaced with a therapy wire onto which the stents 1 - 1c e.g. are held by screwing on their openings 3 and over which they can be targeted. In the still closed or folded state, the stents 1 - 1 c are advanced through the tube catheter 8 in the vein 5 in question, in which the fingers 4, 6 and 7 then expand or open after pushing out of the tube catheter.

When using the stents 1 and 1 a, the release of the therapy or support wire (eg by unscrewing), for example, before pushing out of the therapy catheter 8. When using the stent 1 b or Ic these are, for example, when pushed out of therapy -Catheder 8 still held on the therapy wire and are rotated over this for the insertion of the fingers 6 and 7 in the vein wall and for contracting the vein wall on the therapy wire. Only then is the release of the therapy wire from the respective stent 1 b or 1 c. The deployment and placement of the stents takes place, for example, under ultrasound control (color duplex control). Also side branches of veins can be treated in this way.

It has been assumed above that the stents 1, 1 a, 1 b and 1 c are made of steel, in particular of spring steel. Of course, other vein-compatible materials (also plastics) or alloys may be used, e.g. Magnesium (especially for resorbable stents) or nitinol.

The invention has been described above by means of exemplary embodiments. It is understood that changes and modifications are possible without thereby departing from the inventive concept underlying the invention.

Thus, it is also possible that the stent is formed as a spiral coil of a suitable material, ie similar to the stent 1 c, but without the stent body 2, but preferably with at least one expandable stent end and / or with a to a total Stent-end enlarging diameter. A stent of this type is then also particularly suitable for the treatment of chronic venous insufficiency, ie for a targeted reduction of the vessel lumen cross section by screwing the spiral stent into the vessel wall, without the flow is completely blocked.

Reference number list

Stent Stent body Stent opening, preferably with internal thread Wire finger Vein Spiral-shaped fingers or wire fingers Helical fingers or wire fingers Therapy catheter

Claims

claims

1. A stent (1, 1 a, 1 b) for the reduction of the lumen cross-section of a vessel wall having venous vessel (5), in particular for varicosis treatment as well as for the treatment of chronic venous insufficiency with a stent body (2) with at least one finger [A ₁ 6, 7), characterized in that the stent body (2) for reducing the lumen cross-section of a venous

Vessel (5) is cylindrical in shape, that at least one self-expanding finger (4, 6, 7) of a resilient material on the cylindrical stent body (2) is provided which in a relaxed spread or open state with its free

End further over the outer surface or outer contour of the cylindrical

Stent body (2) stands out as in a closed state and that the free

End for piercing a vessel wall of a venous vessel (5) is formed.

2. Stent according to claim 1, characterized by a plurality of self-spreading fingers which protrude clearly in the open state with their free ends on the outer surface or outer contour of the cylindrical stent body (2).

3. Stent according to claim 1 or 2, characterized in that the fingers (4, 6) in the opened state have a greater distance from a stent axis (STA) than in a folded state.

4. Stent according to claim 2 or 3, characterized in that the fingers [A, 6) are provided distributed around the stent axis (STA).

5. Stent according to one of the preceding claims, characterized in that the fingers (4) in the closed state are oriented parallel or approximately parallel to the stent axis (STA).

6. Stent according to one of the preceding claims, characterized in that the fingers (4) in the open or unfolded state each with the stent axis (STA) an acute angle, i. preferably include an angle less than 45 °.

7. Stent according to one of the preceding claims, characterized in that at least one finger (7) is formed like a helix and in the open state over an end face of the cylindrical stent body (2) protrudes.

8. Stent according to one of the preceding claims, characterized in that the fingers (6, 7) are arranged in the closed state so that it tightly encloses the stent body (2) on a surface surrounding the stent body (STA), and in the open state spirally or helically away from the cylindrical stent body (2) protrudes.

9. Stent according to one of the preceding claims, characterized in that the cylindrical stent body (2) is formed circular cylindrical.

10. Stent according to one of the preceding claims, characterized in that the cylindrical stent body (2) has at least one through opening (3), preferably an opening provided with an internal thread.

1 stent (1 c) for reducing the lumen cross section of a vessel wall having a venous vessel (5), in particular for the treatment of varicosis and for the treatment of chronic venous insufficiency, wherein the stent (1 c) is formed helically or helically and is made of a wire-shaped starting material, characterized in that the stent (1 c) has at least one expandable stent end and / or a stent-end magnifying diameter.

12. Stent according to one of the preceding claims, characterized by its manufacture from a vessel-compatible material, for example from a metallic material, e.g. made of spring steel or magnesium.

13. Stent according to one of the preceding claims, characterized by its preparation from a vascular-compatible plastic or a metal alloy, such as nitinol.

14. Use of a stent (1, I a, 1 b, 1 c) according to one of the preceding claims for reducing the lumen cross section of a vessel wall having a venous vessel (5), in particular for the treatment of varicosis and for the treatment of chronic venous insufficiency.