TENSILE-STRENGTH-ENHANCING TUBE FOR AN IMPLANTABLE ELECTRODE LEAD OR A CATHETER, ELECTRODE LEAD WITH A TENSILE-STRENGTH-ENHANCING TUBE, AND CATHETER WITH A TENSILE-STRENGTH-ENHANCING TUBE

Abstract

A tensile-force-enhancing tube for an implantable electrode lead or a catheter includes a tubular braid which is embedded in an elastomer material, wherein the braid comprises at least one cross thread and at least one axial thread.

Claims

1. A tensile-force-enhancing tube for an implantable electrode lead or a catheter, comprising: a tubular braid which is embedded in an elastomer material, wherein the braid comprises at least one cross thread and at least one axial thread.

2. The tensile-force-enhancing tube according to claim 1, wherein an outer diameter of the tensile-force-enhancing tube is less than or equal to 5 F.

3. The tensile-force-enhancing tube according to claim 1, wherein a wall thickness of the tensile-force-enhancing tube is less than or equal to 0.15 mm.

4. The tensile-force-enhancing tube according to claim 1, wherein the tubular braid comprises at least three cross threads.

5. The tensile-force-enhancing tube according to claim 1, wherein the elastomer material comprises a silicone.

6. The tensile-force-enhancing tube according to claim 1, wherein the at least one cross thread and/or the at least one axial thread comprises a thermoplastic material.

7. The tensile-force-enhancing tube according to claim 1, wherein the at least one cross thread and/or the at least one axial thread comprises polyurethane and/or polypropylene and/or polyamide and/or polyethylene terephthalate.

8. The tensile-force-enhancing tube according to claim 1, wherein the at least one cross thread and/or the at least one axial thread is a multi-filament thread formed from a plurality of individual threads.

9. The tensile-force-enhancing tube according to claim 8, wherein the elastomer material is situated in part between the individual threads of the at least one multi-filament thread.

10. The tensile-force-enhancing tube according to claim 1, wherein the tubular braid and the elastomer material form a fluid-tight tube wall.

11. An implantable electrode lead, which comprises a tensile-force-enhancing tube according to claim 1.

12. The implantable electrode lead according to claim 11, further comprising a coradial coil, which extends at least in some sections within the tensile-force-enhancing tube.

13. The implantable electrode lead according to claim 11, wherein the tensile-force-enhancing tube electrically insulated the coradial coil outwardly at least in some sections.

14. The implantable electrode lead according to claim 11, further comprising at least one ring electrode, wherein the tensile-force-enhancing tube extends through the at least one ring electrode.

15. A catheter, which comprises a tensile-force-enhancing tube according to claim 1.

Description

DESCRIPTION OF THE DRAWINGS

[0031] Further advantages and embodiments of the present invention will be described hereinafter with reference to the figures, in which:

[0032] FIG. 1 shows an embodiment of a tensile-strength-enhancing tube according to the present invention with a cross thread and an axial thread;

[0033] FIG. 2 shows a further embodiment of a tensile-strength-enhancing tube according to the present invention with 8 cross threads and 4 axial threads;

[0034] FIG. 3 shows the braid belonging to the exemplary embodiment according to FIG. 2 on a braid core;

[0035] FIG. 4 shows the braid according to FIGS. 2 and 3 as a tailored segment;

[0036] FIGS. 5A-B shows a further embodiment of a tensile-strength-enhancing tube according to the present invention with a defined outer contour for the assembly of further components;

[0037] FIG. 6 shows an enlarged view of a multi-filament thread which may be used as cross thread and/or as axial thread;

[0038] FIG. 7 shows a further embodiment of a tensile-strength-enhancing tube according to the present invention which has a longitudinal cut in order to facilitate assembly;

[0039] FIG. 8 shows an embodiment of a CRT electrode lead according to the present invention with ring electrodes in the distal region; and

[0040] FIG. 9 shows a longitudinal section of an electrode lead according to the present invention with a coradial coil, in which a tensile-strength-enhancing tube according to the present invention extends through two ring electrodes.

DETAILED DESCRIPTION

[0041] FIG. 1 shows schematically and by way of example an embodiment of a tensile-strength-enhancing tube 1 according to the present invention. The tensile-strength-enhancing tube 1 comprises a tubular braid 11, which is embedded in an elastomer material 12. In FIG. 1, the elastomer material 12, which defined the outer form of the tensile-strength-enhancing tube 1, is shown transparent so that the braid 11 is clearly visible.

[0042] In this exemplary embodiment, the braid 11 comprises a single cross thread 111, which extends helically along the tensile-strength-enhancing tube 1, and a single axial thread 112, which is woven with the cross thread 111 in such a way that the axial thread 112 is guided past intersection points with the cross thread 111 outside and inside the cross thread 111 alternately. The cross thread 111 and the axial thread 112 at the intersection points may additionally be fastened to one another by gluing or welding. The stability of the braid tube 11 as a whole may hereby be further increased.

[0043] The cross thread 111 and the axial thread 112 are preferably made of a thermoplastic material, such as polyurethane (PU), polypropylene (PP), polyamide (PA), or polyethylene terephthalate (PET). The threads 111, 112 may be formed in particular as multi-filament threads, which are formed in each case of a plurality of individual threads 1110. This will be explained in greater detail further below with reference to FIG. 6.

[0044] The elastomer material 12 is an LSR silicone in the present example. In other words, the tensile-strength-enhancing tube 1 in this embodiment has been produced, for example, as an injection-molded part by an overmolding of the braid 11 with liquid silicone rubber (LSR compound). The use of silicone ensures a good flexibility of the tensile-force-transmitting tube 1 with respect to bending stress.

[0045] The axial thread 112 in the tensile-force-transmitting tube 1 fundamentally ensures the (axial) tensile force transmission. The cross thread 111 ensures a good anchoring of the axial thread 112 in the silicone and, in particular, prevents the axial thread 112 from being pulled out from the silicone 12 under tensile load.

[0046] The tensile-force-transmitting tube 1 in accordance with the present exemplary embodiment has an outer diameter of 1.0 mm with a wall thickness of 0.1 mm.

[0047] FIG. 2 shows schematically and by way of example further embodiments of a tensile-strength-enhancing tube 1 according to the present invention with a total of 8 cross threads 111 and 4 axial threads 112. Apart from the different number of threads, that said above with reference to FIG. 1 also applies for the variant according to FIG. 2.

[0048] FIG. 3 shows schematically and by way of example the tri-axial braid 11, belonging to the exemplary embodiment according to FIG. 2, on a braid core 3.

[0049] The structure of the braid 11 is shown particularly clearly on the basis of FIG. 4, which illustrates the braid 11 according to FIGS. 2 and 3 as a tailored segment in a simple perspective view. It is clear that 4 of the cross threads 111 of the braid 11 extend helically along the tensile-strength-enhancing tube 1 with a first direction of rotation (as left-handed helix), whereas the other 4 cross threads 111 extend helically with a second, opposite direction of rotation (i.e., as right-handed helix). The 4 axial threads 112 are arranged here uniformly (i.e., each distanced at 90 from one another) around the cross-section of the tensile-strength-enhancing tube 1. They are guided past the cross thread 111 in part inside and in part outside said cross thread. As already explained above in respect of the exemplary embodiment according to FIG. 1, the axial threads 111 and the cross threads 112 may additionally be adhesively bonded or welded at their intersection points, and the cross threads 112 may also be adhesively bonded or welded at their intersection points with themselves.

[0050] FIGS. 5A-B show a further variant which differs from the exemplary embodiment according to FIG. 2 merely by the form of the elastomer material 12. As shown in FIG. 5A, the braid 11 has the same structure as explained above with reference to FIGS. 2-4. However, in this exemplary embodiment, the tensile-strength-enhancing tube 1 has been manufactured as an injection-molded part, which has a defined outer contour, for example so as to allow the assembly of further components. This can be seen particularly well on the basis of FIG. 5B, in which the LSR silicone 12, which defines the outer contour of the tensile-strength-enhancing tube 1 is not shown transparent. Thus, the plurality of outer contour elements 122 are provided in the form of annular portions, in which the outer radius of the tensile-strength-enhancing tube 1 is increased. It is of course also conceivable that the tensile-strength-enhancing tube could be produced with defined inner contours (not illustrated).

[0051] FIG. 6 shows an enlarged view of a cross thread 11 as may be used in a tensile-strength-enhancing tube 1 according to the above-described exemplary embodiments. The cross thread 111 is embodied as a multi-filament thread from a number of individual threads 1110. A cross thread 111 is shown here by way of example, however, the one or more axial threads 112 according to the above-described exemplary embodiments may also be multi-filament threads of this kind. The shown multi-filament thread 111 is formed of a plurality of individual threads or individual filaments 1110, which may be stretched, woven or twisted. In the finished tensile-strength-enhancing tube 1, the LSR silicone 12 is preferably situated in part between the individual threads 1110. For example, during the production pf the tensile-strength-enhancing tube 1, the LSR compound 12 may flow around the individual threads 1110 and infiltrate the gaps between them. In other words the silicone compound may become positioned between the individual filaments 1110 during the overmolding of the braid 11. As a result of this mechanical anchoring, the threads 111, 112 may be prevented from being pulled out of the silicone. With use of multi-filament threads 111, 112, a stable anchoring, with particularly high tensile strength, of the braid 11 in the silicone 12 may thus be achieved.

[0052] FIG. 7 shows schematically and by way of example a further embodiment of a tensile-strength-enhancing tube 1 according to the present invention. This differs from the exemplary embodiment according to FIG. 2 in that the tensile-strength-enhancing tube 1 has a longitudinal cut L to facilitate the assembly. The provision of such a longitudinal cut L may be advantageous for the assembly, since the braid tube 11 in this exemplary embodiment is substantially neither radially nor axially extensible.

[0053] FIG. 8 shows an exemplary embodiment of an electrode lead 2 according to the present invention. The shown electrode lead 2 is intended for cardiac resynchronization therapy (CRT). It has an elongate lead body 20, wherein in a distal region a head electrode 26, and a plurality of ring electrodes 22 are arranged on the lead body 20. The electrodes 22, 26 are electrically active and are intended for the contacting of bodily tissue in the coronary sinus. FIG. 8 also shows an electrode fixing sleeve 25 and a plurality of plug contacts 24 for connection to a pulse emitter (not shown) in a proximal region of the electrode lead 2.

[0054] In the distal region of the electrode lead 2, which is to be introduced into the coronary sinus, the lead body 20 must be relatively flexible in respect of bending stresses and at the same time must be able to withstand the tensile forces occurring during implantation, repositioning and/or explantation. This is possible in the shown exemplary embodiment due to the provision of a tensile-force-transmitting tube 1 according to the present invention in the aforesaid distal region. The necessary tensile strength and at the same time the bending flexibility of the electrode lead 2 necessary for the application may hereby be ensured.

[0055] FIG. 9 shows a longitudinal cut of an electrode lead 2 according to the present invention in the region of a ring electrode 22. A conductive coradial coil 23 extends here within the tensile-force-transmitting tube 1 according to the present invention, which in the present case is shown merely schematically (i.e., without structural details of the braid 11). The tensile-force-transmitting tube 1 electrically insulates the coradial coil 3 and, by way of its fluid-tight design, additionally prevents the infiltration of blood into the interior of the lead body 20.

[0056] The tensile-force-transmitting tube 1 extends through the ring electrodes 22. By way of such an arrangement, the mechanical requirements in respect of tensile strength and flexibility with respect to bending stress may be satisfied, in particular also in the region of ring electrodes 22.

[0057] So that the electrodes 22, 26 do not protrude beyond the lead body 20 of the electrode lead 2, thus resulting in the creation of steps at the surface of the lead body 20 by the electrodes 22, 26, the tensile-force-transmitting tube 1 in FIG. 9 is encased by a cover tube 4 in the regions not enclosed by electrodes 22, 26. The cover tube 4 may be made, for example, from silicone or polyurethane.

[0058] In an alternative embodiment of an electrode lead 2 according to the present invention, instead of a conductive coradial coil 23 for electrical connection between the electrodes 22, 26 and the plug contacts 24, one or more conductive cables may also be used (not shown). The conductive cables extend here within the tensile-force-transmitting tube 1 of the electrode lead according to the invention. To guide the conductive cables and in order to insulate the conductive cables with respect to one another, a multi-lumen tube is provided within the tensile-force-transmitting tube 1. The aforementioned multi-lumen tube may advantageously be formed by the elastomer material 12 that is used to overmold the braid 11 with liquid silicone rubber (LSR compound) to form the tensile-strength-enhancing tube 1. A multi-lumen tube is understood to mean a tube in the interior of which a plurality of separate lumens extend from one end of the tube to the other end of the tube.

[0059] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings of the disclosure. The disclosed examples and embodiments may include some or all of the features disclosed herein. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention, which is to be given the full breadth thereof. Additionally, the disclosure of a range of values is a disclosure of every numerical value within that range, including the end points.

LIST OF REFERENCE NUMERALS

[0060] 1 tensile-strength-enhancing tube [0061] 11 braid [0062] 111 cross thread [0063] 112 axial thread [0064] 1110 individual threads [0065] 12 elastomer material [0066] 122 outer contour elements [0067] 2 implantable electrode lead [0068] 20 line body [0069] 22 ring electrode [0070] 23 coradial coil [0071] 24 plug contacts [0072] 25 electrode fixing sleeve [0073] 26 head electrode [0074] 3 braid core [0075] 4 cover tube [0076] L longitudinal cut