IMPLANTABLE LEAD

Abstract

The present invention relates to an implantable lead comprising at least one conductive wire and one electrical connector, the electrical connector configured to be connected to an implantable medical device such as a cardiac stimulation, defibrillation and/or neuromodulation device, wherein the electrical connection between the conductive wire and the connector is effected by a first hypotube welded to the conductive wire and welded to a second hypotube of the electrical connector. The present invention also relates to a method for electrically connecting the at least one conductive wire of the implantable lead to the electrical connector.

Claims

1. An implantable lead comprising: at least one conductive wire; and an electrical connector, the electrical connector configured to be connected to an implantable medical device such as a cardiac stimulation device, defibrillation device and/or neuromodulation device, wherein an electrical connection between the conductive wire and the connector is formed by a first hypotube welded to the conductive wire and welded to a second hypotube of the electrical connector.

2. The implantable lead according to claim 1, wherein the first hypotube is partially housed in the second hypotube such that a portion of the first hypotube protrudes out of the second hypotube.

3. The implantable lead of claim 1, wherein the first hypotube is welded to the second hypotube such as to electrically connect the first hypotube to the second hypotube.

4. The implantable lead of claim 3, wherein the welding between the at least one conductive wire and the first hypotube is made at a first end of the first hypotube through which the at least one conductive wire and/or at a second end of the first hypotube, the second end being opposite the first end.

5. The implantable lead of claim 1, comprising a plurality of conductive wires, such that each conductive wire is electrically connected to a respective first hypotube.

6. The implantable lead of claim 1, comprising a plurality of conductive wires, such as at least two conductive wires are electrically connected to a same first hypotube.

7. The implantable lead of claim 1, wherein the one or more weldings made to establish the electrical connections is/are a laser weld(s).

8. The implantable lead of claim 1, wherein the at least one conductive wire is a single-stranded or multi-stranded conductive wire such that the conductive wire has a diameter of less than 150 microns or 0.45 French.

9. A method for electrically connecting at least one conductive wire of an implantable lead to an electrical connector, the electrical connector configured to be connected to an implantable medical device such as a cardiac stimulation device, defibrillation and/or neuromodulation device comprising the steps of: housing the at least one conductive wire of the lead in a first hypotube; electrically connecting the at least one conductive wire to the first hypotube; at least partially housing the first hypotube in a corresponding second hypotube of the electrical connector; and electrically connecting the first hypotube with the second hypotube.

10. The method for of claim 9, wherein one or more of the electrically connecting steps comprises performing a laser weld.

11. The method of claim 10, wherein the welding is made at a first end of the first hypotube through which the at least one conductive wire is inserted and/or at a second end of the first hypotube, the second end opposed to the first end.

12. The method of claim 10, wherein partially housing the first hypotube in the second hypotube comprises inserting the first hypotube into the second hypotube such that a portion of the first hypotube protrudes out of the second hypotube.

13. The method of claim 10, further comprising housing a plurality of conductive wires in a plurality of first hypotubes, such that each conductive wire is electrically connected to a respective first hypotube.

14. The method of claim 10, wherein the at least one conductive wire is a single-stranded or multi-stranded conductive wire such that the conductive wire has a diameter of less than 150 microns or 0.45 French.

15. An implantable medical device for cardiac pacing, defibrillation, or/and neuromodulation comprising: an implantable lead comprising an electrical connector and at least one conductive wire electrically connected to the connector, wherein the electrical connection between the conductive wire and the connector is formed by a first hypotube welded to the conductive wire and welded to a second hypotube of the electrical connector.

16. The implantable medical device of claim 15, wherein the first hypotube is partially housed in the second hypotube such that a portion of the first hypotube protrudes out of the second hypotube.

17. The implantable medical device of claim 15, wherein the first hypotube is welded to the second hypotube such as to electrically connect the first hypotube to the second hypotube.

18. The implantable medical device of claim 17, wherein the welding between the at least one conductive wire and the first hypotube is made at a first end of the first hypotube through which the at least one conductive wire and/or at a second end of the first hypotube, the second end being opposite the first end.

19. The implantable medical device of claim 15, comprising a plurality of conductive wires, such that each conductive wire is electrically connected to a respective first hypotube.

20. The implantable medical device of claim 15, wherein the at least one conductive wire is a single-stranded or multi-stranded conductive wire such that the conductive wire has a diameter of less than 150 microns or 0.45 French.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The invention and its advantages will be explained in more detail in the following by means of preferred embodiments and relying in particular on the following example figures, in which:

[0024] FIG. 1 schematically shows an implantable lead according to the prior art.

[0025] FIG. 2a represents a partial view of the implantable lead according to the present invention.

[0026] FIG. 2b shows a sectional view of the implantable lead e shown in FIG. 2a.

[0027] FIG. 3a represents a step of the method for electrically connecting a conductive wire of an implantable lead to an electrical connector according to an embodiment of the present invention.

[0028] FIG. 3b represents a step of the method for electrically connecting a conductive wire of an implantable lead to an electrical connector according to an embodiment of the present invention.

[0029] FIG. 3c represents a step of the method for electrically connecting a conductive wire of an implantable lead to an electrical connector according to an embodiment of the present invention.

[0030] FIG. 3d represents a step of the method for electrically connecting a conductive wire of an implantable lead to an electrical connector according to an embodiment of the present invention.

DETAILED DESCRIPTION

[0031] The invention will now be described in more detail using advantageous embodiments in an exemplary method and with reference to the drawings. The described embodiments are merely possible configurations and it should be borne in mind that the individual features as described above may be provided independently of each other or may be omitted altogether when the implementation of the present invention.

[0032] FIG. 2a schematically illustrates a partial view of an implantable lead 1 at its proximal end. FIG. 2a shows a connector 3 of the implantable lead 1. The connector 3 has a cylindrical shape of axis A and comprises at its distal end 5 a distal pin 7 configured to be connected to a terminal of an implantable medical device (not shown) such as a cardiac pacing, defibrillation, and/or neuromodulation device.

[0033] The connector 3 shown in FIG. 2a is of multipolar type because it is provided with three contacts 9a, 9b, 9c. In a variant, the connector 3 may comprise more or less than three contacts. In another variant, the connector 3 may comprise only one contact.

[0034] The connector 3 can be made from biocompatible conductive materials such as 316L stainless steel or a metal alloy, MP35N, for example. The material of connector 3 can be selected to be biocompatible, conductive and to suitably transmit electrical signals from an electrical stimulation device (not shown).

[0035] The implantable lead 1 also comprises conductive wires 11a, 11b, 11c which allows electrical connection of the contacts 9a, 9b, 9c of the connector 3 to one or several electrodes (not shown) of the lead 1. In the illustrated embodiment illustrated in FIG. 2a, the conductive wires 11a, 11b, 11c are each multi-stranded conductive wires such that the diameter of each multi-stranded conductive wire 11a, 11a, 11c is less than 150 micrometers. The individual conductive wires each constituting multi-stranded conductive wires 11a, 11b, 11c are not electrically isolated from each other. However, the multi-stranded conductive wires 11a, 11b, 11c are electrically isolated from each other.

[0036] In a variant, the conductive wires 11a, 11b, 11c are single conductive wires such that the diameter of each conductive wire 11a, 11b, 11c, that is to say of each single-wire conductive wire, is less than 150 micrometers. In addition, single conductive wires 11a, 11b, 11c are electrically isolated from each other.

[0037] According to the present invention, the conductive wires 11a, 11b, 11c are each housed and welded to a first hypotube 13a, 13b, 13c; and each first hypotube 13a, 13b, 13c is itself housed and welded to a second hypotube 15a, 15b, 15c of the connector 3 at the proximal end 17 of the connector 3.

[0038] The axis A of the connector 3 is parallel to the respective axes B, C of the second hypotubes 15a, 15b, 15c and of the first hypotube 13a, 13b, 13c. The axis C of each first hypotube 13a, 13b, 13c coincides with the axis B of the second hypotube 15a, 15b, 15c in which it is inserted.

[0039] The second hypotubes 15a, 15b, 15c are housed in the connector 3 and electrically connected with the contacts 9a, 9b, 9c. A length portion L1 of each second hypotube 15a, 15b, 15c protrudes out of the connector 3.

[0040] The first hypotubes 13a, 13b, 13c are housed in a second corresponding hypotube 15a, 15b, 15c so that a portion of length L2 of each first hypotube 13a, 13b, 13c protrudes out of the second hypotube 15a, 15b, 15c.

[0041] Alternatively, several conductive wires can be housed in the same first hypotube. The number of first hypotubes, of second hypotubes and of conductive wires, each of which is three in the implantable lead 1 shown in FIG. 2a, is thus illustrative and does not constitute a numerical limitation of the present invention.

[0042] FIG. 2a will be further described in the following in combination with FIG. 2b which illustrates a partial sectional view of the lead 1. Even though FIG. 2b illustrates only one of the first and second hypotubes 13a, 15a of FIG. 2a, the description of the hypotubes 13a, 15a also applies to the other hypotubes 13b, 13c, 15b, 15c of the implantable lead 1. The elements with the same numeral references already used for the description of FIG. 2a will not be described in detail and reference is made to their descriptions above.

[0043] FIG. 2b shows the second hypotube 15a which is partially housed in the connector 3. The second hypotube 15a is electrically connected (not shown) to one of the contacts 9a, 9b, 9c of the connector 3. The second hypotube 15a comprises a hollow portion 19 of internal diameter d1 and a wall 21 made of stainless steel. The second hypotube 15a has an outer diameter D1.

[0044] The first hypotube 13a also comprises a hollow portion 23 the internal diameter of which is d2 and a wall 25 made of stainless steel. The second hypotube 15a has an outer diameter D2.

[0045] The outer diameter D2 of the first hypotube 13a is less than or equal to the internal diameter d1 of the second hypotube 15a so that it is possible to insert the first hypotube 13a in the hollow portion 19 of the second hypotube 15a. As illustrated in FIG. 2b, the outer diameter D2 of the first hypotube 13a is dimensioned so that the wall 25 of the first hypotube 13a is in contact with the wall 21 of the second hypotube 15a in order to improve the electrical contact and the maintaining the first hypotube 13a in the second hypotube 15a.

[0046] The diameter D3 of the conductive wire 11a is smaller than the internal diameter d2 of the first hypotube 13a. In particular, the conductive wire 11a according to the present invention has a diameter D3 of less than 150 micrometers. The internal diameter d2 of the first hypotube 13a comprised between 150 micrometers and 350 micrometers. Thus, the dimensions d2, D2 of the first hypotube 13a make it possible to accommodate the difference in size between the internal diameter d of the second hypotube 15a of the connector 3 and the diameter D3 of the conductive wire 11a. Therefore, the first hypotube 13a, in addition to allowing an electrical connection, is also a means of adaptation to accommodate the difference in size between the conductive wire 11a and the second hypotube 15a of connector 3.

[0047] In the embodiment illustrated in FIG. 2b, the conductive wire 11a is inserted into the hollow portion 23 of the first hypotube 13a and is welded at one end 27 of the first hypotube 13a. The welding of the lead 11a to the first hypotube 13a will be further described with reference to FIG. 3b.

[0048] In the embodiment illustrated in FIG. 2b, the first hypotube 13a is partially housed in the second hypotube 15a so that there is a distance L3 between the end 27 of the first hypotube 13a and a closed end 29 of the second hypotube 15a.

[0049] According to another embodiment, the first hypotube 13a can be inserted as far as a stop in the second hypotube 15a, so that there is contact between the end 27 of the first hypotube 13a and the closed end 29 of the second hypotube 15a. Alternatively, not shown in FIG. 2b, the end 29 of the second hypotube 15a may be a partially closed end or an open end.

[0050] The first hypotube 13a is welded to the second hypotube 15a outside the connector 3 at a junction zone 31 located between the wall 25 of the first hypotube 13a and an open end 33 of the second hypotube 15a. Thus, achieving the weld between the first hypotube 13a and the second hypotube 15a is facilitated because it can be performed outside the second hypotube 15a and connector 3, providing more space and visibility to an operator to perform the weld. In addition, the weld zone 31 between the first hypotube 13a and the corresponding second hypotube 15a is distinct from the weld zones of the other first hypotubes 13b, 13c and of their respective second hypotubes 15b, 15c (see FIG. 2a, not shown in FIG. 2b). Thus, an operator may, for example, perform the electrical connection at the first hypotube 13a without having to rework the electrical connections of the other first hypotubes 13b, 13c.

[0051] According to an embodiment of the present invention, the welding between the conductive wire 11a and the first hypotube 13a, as well as the welding at the junction zone 31 between the first hypotube 13a and the second hypotube 15a are performed by laser welding. Laser welding notably makes it possible to achieve a sealed weld, and also allows precise welding particularly suitable for the scale of implantable lead connectors of medical devices.

[0052] FIGS. 3a to 3d schematically illustrate steps of the method for electrically connecting the conductive wire 11 a of the implantable lead 1 to the connector 3 according to another embodiment.

[0053] The elements with the same numerical references already used for the description of FIGS. 2a and 2b will not be described again in detail, and reference is made to their descriptions above.

[0054] FIG. 3a illustrates the first step in which the lead 11a is inserted through an open end 35 of the first hypotube 13a into the hollow portion 23 of the first hypotube 13a. In one variant, a plurality of conductive wires may be introduced into the first hypotube 13a.

[0055] According to the embodiment illustrated in FIG. 3a, the conductive wire 11a has a diameter D3 of less than 150 micrometers and the hollow portion 23 of the first hypotube 13a has an internal diameter d2 of between 150 and 350 micrometers.

[0056] FIG. 3b illustrates a longitudinal sectional view along the axis C of the first hypotube 13a at the step wherein the conductive wire 11a is welded to the first hypotube 13a to electrically connect them.

[0057] According to the embodiment illustrated in FIG. 3b, the conductive wire 11a has been introduced through the open end 35 of the first hypotube 13a to the end 27 opposite the end 35; and welded at the end 27 of the first hypotube 13a.

[0058] According to other embodiments, the conductive wire 11a may be welded at the end 35 of the first hypotube 13a, by which the conductor 11a is introduced, or at both ends 27, 35 of the first hypotube 13a, as long as a connection between the conductive wire 11a and the hypotube 13a is permitted.

[0059] The welding between the conductive wire 11a and the first hypotube 13a is performed by a laser weld. Thus, a smooth and rounded surface 37 is formed at the end 27 of the first hypotube 13a and the electrical contact between the conductive wire 11a and the first hypotube 13a is obtained.

[0060] The laser beam is not directed and applied directly to the lead 11a, but on one end 27, 35 of the first hypotube 13a in which the lead 11a is housed, the risk of damaging or destroying the conductive wire 11a, especially when its diameter is less than 150 micrometers, because of the energy released by the laser beam, is reduced.

[0061] FIG. 3c illustrates the insertion step of the first hypotube 13a to which the conductive wire 11a is welded.

[0062] The end 27 of the first hypotube 13a is inserted into the hollow portion 19 of the second hypotube 19 so that a portion of length L2 of the first hypotube 13a remains outside the second hypotube 15a, as illustrated in FIGS. 2a and 2b.

[0063] The next step of the method for electrically connecting the conductive wire 11a of the implantable lead 1 to the connector 3 is illustrated in FIG. 3d.

[0064] This step consists of welding the first hypotube 13a to the second hypotube 15a at the junction 31 located outside the connector 3. This step allows to electrically connect the second hypotube 15a of the connector 3 to the first hypotube 13a, itself electrically connected to the conductive wire 11a during the step illustrated in FIG. 3b. Thus, the first hypotube 13a serves as an intermediate for the electrical connection between the conductive wire 11a and the second hypotube 15a of the connector 3.

[0065] The use of the first hypotube 13a, making it possible to make the intermediate between the conductive wire 11a and the connector 3, then makes possible an electrical connection between a connector comprising a hypotube with standard dimensions of between 350 and 500 micrometers and a conductive wire of diameter less than 150 micrometers.

[0066] The description of the steps for electrically connecting the conductive wire 11a to the connector 3 of the lead 1 with reference to FIGS. 3a to 3d applies integrally to the connection of the conductive wires 11b and 11c to the connector 3 of the lead.

[0067] Those skilled in the art will appreciate that the present invention can be applied essentially to any type of implantable lead whose electrical connector is provided with at least one hypotube.