Patent Application
20170182311
This Utility Patent Application claims priority to European Patent Application No. EP 15202412.1, filed on Dec. 23, 2015, which is incorporated herein by reference.
One aspect relates generally to a process for electrically contacting a coated lead. More specifically, one aspect relates to a process, an electrically contacted lead and a medical device comprising an electrically contacted lead.
Making electrical contact with an electrically conductive lead can often represent a significant challenge. In order to take advantage of beneficial properties of an electrical lead, such as good electrical conductivity and good durability, the contact to the lead itself must also display similar beneficial properties. Such considerations are particularly pertinent for example when electrically contacting leads in medical devices. In devices which are introduced into the body, it is desirable to employ thin leads, which can represent a challenge to electrically contact due their size. Furthermore, a very high value is placed on reliability in medical devices such as Cardiac Pacemakers, Implantable Cardioverter Defibrillation Devices and Cardiac Resynchronisation Devices, especially in terms of resistance to physical fatigue. Invasive surgery is required to implant medical devices into the body or remove or replace parts, and it is highly desirable for the individual components of the device to have a long working life in order to reduce the requirement for surgical intervention. Furthermore, it is desirable for the working life to have a low variance. One component of a medical device which is exposed to a particularly high amount of stress during normal operation is the lead and the electrical connections thereto.
Document U.S. Pat. No. 7,364,479 B1 discloses a method for contacting a lead by crimping. Direct crimping can result in a contact which is lost over time due to physical movement. Furthermore, the direct crimping method is not suitable for multi-core leads since contact would be made to the cores indiscriminately.
Document US 2013/0338745 A1 discloses a method for contacting individual conductive cores of a cable which includes multiple conductive cores. The individually coated conductive cores are fed through the lumens of a ring, and electrical contact is made with the individual cores by piercing. This method suffers at least from the disadvantages associated with moveable parts.
For these and other reasons, a need exists for the present invention.
One embodiment is generally based on the object of overcoming at least one of the problems encountered in the state of the art in relation to electrical contacts with leads.
More specifically, one embodiment is based on the object of providing a process for electrically contacting a lead, which provides for one or more selected from the following group of advantages: an improved electrical contact, an improved durability and a more flexible process.
One object of one embodiment is to provide a process which is suitable for electrically contacting a thin lead, in one embodiment while providing for one or more selected from the following group of advantages: an improved electrical contact, an improved durability and a more flexible process.
Another object of one embodiment is to provide a process which is suitable for electrically contacting a lead for use in a medical device, in one embodiment a thin lead. In one embodiment, it is preferred for electrically contacting a lead in a bio-compatible device, in one embodiment while providing for one or more selected from the following group of advantages: an improved electrical contact, an improved durability and a more flexible process. One aspect of this object is to provide a process for connecting a lead which fulfils the requirements laid out in the “Guidance for the Submission of Research and Marketing Applications for Permanent Pacemaker Leads and for Pacemaker Lead Adaptor 510(k) Submissions” issued by the “Center for Devices and Radiological Health” of the US Food and Drug Administration. A further object is provide a method for electrically contacting a multi-core lead, in particular for discriminately contacting a single core thereof. This has long been attempted and there are various approaches provided in the art. Some of these have been discussed above. There remains, however, a need for further improvement of such electrical contacts and methods for making them.
The accompanying drawings are included to provide a further understanding of embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and together with the description serve to explain principles of embodiments. Other embodiments and many of the intended advantages of embodiments will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.
One aspect is now further illustrated using figures which are not to be considered as limiting the scope. In brief, the figures illustrate the following:
In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.
It is to be understood that the features of the various exemplary embodiments described herein may be combined with each other, unless specifically noted otherwise.
Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof.
A contribution to achieving at least one of the above described objects is made by the subject matter of the category forming claims. A further contribution is made by the subject matter of the dependent claims, which represent specific embodiments.
A contribution to achieving at least one of the above described objects is made by the following embodiments.
20. An electrically contacted lead obtainable by a method according to any of the preceding embodiments.
The features introduced in relation to the above process embodiments apply mutatis mutandis as aspects of this embodiment.
Fatigue resistance is measured according to the test described in “prEN 45502 Parts 2 & 3 CEN/CENELEC, Active Implantable Medical Devices—Brady and Tachy Lead Tests Draft/Standard”.
Electrical contacts were made to 15 cm long leads having a 0.2 mm diameter core of rhodium/platinum alloy (20% rhodium, 80% platinum, by mass) and a 20 μm coating of PTFE. 1 cm from each end of the lead, an electrical contact was made as follows: First, a via hole was made through the PTFE coating by laser ablation using a Varydisk laser available from Dausinger+Giesen GmbH. The via hole had a circular cross section of 60 μm diameter. Second, a layer of PEDOT:PSS was coated by spraying over the via hole in a cylindrical layer having a thickness of 30 μm and a cylinder length of 200 μm. The lead was heated to 100° C. for 5 hours to dry the PEDOT:PSS layer. Third, a cylindrical ring of rhodium/platinum alloy (20% rhodium, 80% platinum, by mass) with outer diameter of 350 μm, an inner diameter of 260 μm and a cylinder length of 500 μm, available from Heraeus Deutschland GmbH & Co. KG, was threaded over the lead, positioned so as to cover the via hole with applied PEDOT:PSS layer and crimped tight onto the lead using a multi-jaw chuck.
The lead was provided as in example 1 and electrical contact was made 1 cm from each end of each lead as follows: First, a via hole was made through the PTFE coating by laser ablation using a Varydisk laser available from Dausinger+Giesen GmbH. The via hole had a circular cross section of 60 μm diameter. Second, a cylindrical ring as in example 1 was threaded over the lead, positioned so as to cover the via hole and a contact was made between the ring and the core of the lead by soldering with gold at 700° C.
The lead was provided as in example 1 and electrical contact was made 1 cm from each end of each lead as follows: First, a via hole was made through the PTFE coating by laser ablation using a Varydisk laser available from Dausinger+Giesen GmbH. The via hole had a circular cross section of 60 μm diameter. Second, a cylindrical ring as in example 1, but with a 60 μm via hole was provided. The ring was threaded over the lead and positioned such that the via in the ring was over the via in the coating of the lead. Contact was made between the ring and the core of the lead by soldering through the two superimposed via holes with gold at 700° C.
A lead was provided as in example 1 and electrical contact was made 1 cm from each end of each lead as follows: First, a cylindrical ring as in example 1 was threaded over the lead and positioned 1 cm from the end of the lead. Second, the ring was crimped using a multi-jaw chuck to contact the ring with the core of the lead.
Properties of the Contacted Leads
For each of the examples (1, 2a, 2b & 3), 5 leads were contacted as described. Each contacted lead was tested for fatigue resistance. The success rate of contacting the leads and the results for fatigue resistance are illustrated in table 1.
| Number | Date | Country | Kind |
|---|---|---|---|
| 15202412.1 | Dec 2015 | EP | regional |
