Connection for medical devices with integrated antenna

Abstract

Implantable medical device (1), comprising: a housing (2) with an electrical feedthrough (4) comprising at least a first feedthrough conductor (41) and a second feedthrough conductor (42), a terminal block (3) connected to the housing (2), wherein the terminal block (3) comprises a plug socket (5) for an electrode lead, which is designed to accommodate a plug of an electrode lead, wherein the plug socket (5) has a first electrical electrode lead contact (51) and a second electrical electrode lead contact (52), an antenna located in the terminal block (3), a first conductor (61) that electrically connects the first electrical contact (51) to the first feedthrough conductor (41), and a second conductor (62) that electrically connects the second electrical contact (52) to the second feedthrough conductor (42), where the antenna is formed by or includes a first section (600) of the first conductor (61).

Description

[0001] The present invention relates to an implantable medical device.

[0002] For active implantable medical devices (AIMDs), i.e., implantable medical devices containing a power source such as a battery with RF telemetry systems (e.g., for home monitoring), antenna design principles dictate the isolation of the antenna from other electrically conductive components of the medical device. However, an often conflicting design requirement is to minimize the volume of the device to increase patient comfort, etc. This is because in smaller devices, the electrically conductive components such as the antenna connector, charging coil, etc., are naturally located closer together.

[0003] Known solutions include positioning and orienting the antenna in such a way that the electrically conductive components remain as isolated as possible, which also includes one or two separate feedthroughs for connecting the device housing to provide the connection for the RF signals transmitted and received by the antenna, as well as at least one additional connection to the line contacts for the therapeutic function of the medical device.

[0004] Based on this, the problem to be solved by the present invention is to provide an implantable medical device that enables desirable antenna performance in a smaller device volume.

[0005] This problem is solved by an implantable medical device having the features of claim 1. Preferred embodiments of the invention are described below.

[0006] According to claim 1, an implantable medical device is disclosed comprising: - a housing with an electrical feedthrough comprising at least a first feedthrough conductor and a second feedthrough conductor (e.g. in the form of a pin), - a terminal block connected to the housing, wherein the terminal block comprises a plug socket for an electrode line, which is designed to receive a plug of an electrode line, wherein the plug socket has a first electrical electrode line contact and a second electrical electrode line contact, - an antenna arranged in the head, wherein the implantable medical device is configured to transmit and / or receive RF signals via the antenna, in particular for communication with an external device, - a first conductor electrically connecting the first electrical line contact to the first feedthrough conductor, and - a second conductor connecting the second electrical line contact to the second feedthrough conductor, wherein the antenna is formed by or comprises a first portion of the first conductor, wherein in particular the implantable medical device is configured to conduct an electrical current from the first feedthrough conductor via the first portion of the first conductor to the first electrical electrode lead contact, in particular for applying electrical stimulation to tissue of a patient via an electrode lead connected to the plug socket.

[0007] In particular, the present invention thus eliminates the need for a dedicated far-field telemetry antenna by integrating a radiating element into at least one of the conductors (or multiple conductors, as described below) of the external wiring in the terminal block (i.e., the electrical connections between the receptacle and the electrical feedthrough), thereby enabling desirable antenna performance in a smaller device volume.

[0008] Furthermore, the present invention contributes to solving a central problem in antenna design for implanted medical devices, namely the colocation of the RF antenna with other conductive components of the device, such as electrodes, electrical electrode lead contacts, external wiring, and charging coils. Device miniaturization forces designers to consider minimizing the spacing between these components when antenna performance dictates an inverse relationship (i.e., closer spacing degrades radiation efficiency). Advantageously, the present invention simplifies this challenge by combining the antenna and at least one conductor of the external wiring, thereby reducing the number of conductive components required in the terminal block and enabling device miniaturization with minimal adverse effects on antenna performance.

[0009] In a preferred embodiment of the present invention, the antenna is formed by the first section of the first conductor, wherein this first section is also referred to as the antenna section of the first conductor.

[0010] In particular, when the antenna comprises or is formed by the first portion of the first conductor, the first portion of the first conductor is configured to conduct a signal from the first feedthrough contact to the first electrode lead contact, e.g., for applying electrical stimulation to a patient's tissue via an electrode connected to the electrode lead contact and simultaneously transmitting or receiving RF signals.

[0011] For this purpose, in a preferred embodiment, the first section of the first conductor may comprise a plurality of annular or meander-shaped sections which are connected to one another, wherein in particular the annular or meander-shaped sections may be integrally connected to one another or welded to one another.

[0012] According to a further preferred embodiment, the first conductor comprises - in addition to the first section of the first conductor which serves as an antenna - a second section which connects the first section of the first conductor to the first electrical electrode line contact.

[0013] In a preferred embodiment, the second portion of the first conductor comprises an impedance discontinuity, in particular for isolating the antenna, ie the first portion of the first conductor, from the first electrical electrode line contact.

[0014] In a preferred embodiment, the impedance discontinuity is formed by a narrow section of the second part of the first conductor, wherein the narrow section has a cross-sectional area that is smaller than the cross-sectional area of ​​the first conductor on both sides of the narrow section.

[0015] Furthermore, in a preferred alternative embodiment, the second section of the first conductor comprises an inductance, in particular for isolating the antenna section from the first electrode line contact. In particular, the inductance can be formed by a coil.

[0016] According to a further preferred embodiment, the antenna is formed by the first portion of the first conductor and a first portion of the second conductor, wherein the first portions of the first and second conductors are capacitively coupled.

[0017] Furthermore, in a preferred embodiment, the implantable medical device comprises a filter network, wherein the filter network is configured to separate an RF signal transmitted or received by the antenna from a low frequency signal received (detected) or applied by an electrode lead connected to the receptacle.

[0018] In the following, embodiments of the present invention as well as further features and advantages of the present invention are described with reference to the figures, wherein Fig. 1 shows a schematic representation of an embodiment of the present invention, Fig. 2 shows an embodiment of the present invention, Fig. Figure 3 shows an embodiment of the present invention incorporating an impedance discontinuity, and Fig. Figure 4 shows a schematic representation of an embodiment of the present invention for using two outer wiring conductors to form an antenna.

[0019] Fig. Figure 1 shows a block diagram of an embodiment of an implantable medical device 1 according to the present invention. The implantable medical device (e.g., implantable pulse generator) 1 comprises a housing (can) 2 enclosing an electronic circuit. The device 1 further comprises a terminal block 3 and an electrical feedthrough 4 that hermetically seals the housing 2 and allows electrical signals to be conducted into and / or out of the housing 2 via at least one first and one second feedthrough contact 41, 42, which can be configured, for example, as pins.

[0020] The terminal block 3 comprises a plug socket 5 with a first electrical electrode line contact 51 and a second electrical electrode line contact 52, which are designed to receive a plug of an electrode line (not shown) (cf. e.g. also Fig. 2) and can make electrical contact when the plug of the electrode lead is arranged in the connection block 3. An electrode lead (not shown) can be connected to the plug socket 5 and enables the recording of physiological signals (e.g. cardiac signals) from a patient and / or the application of therapy in the form of electrical stimulation to the patient, e.g. to the patient's heart. However, the present invention is not limited to pacemakers and applies to all devices that use an antenna and an electrode lead that are connected to an electronic circuit via an electrical feedthrough. In particular, it is also conceivable for the therapeutic signal to be applied to nerve tissue, e.g. when the implantable medical device 1 is designed as a neurostimulator.

[0021] Each electrical electrode lead contact 51, 52 is connected to feedthrough conductors 41, 42 (e.g., feedthrough pins) of the electrical feedthrough 4 via an external wiring conductor 61, 62. One of the conductors, i.e., the second conductor 62 of the external wiring, is of the conventional design. However, the other (first conductor 61) includes a first radiating portion 600 located in front of the portion of the first conductor contacting the electrode lead contact. This first radiating portion 600 of the first conductor 61 of the external wiring acts as an antenna of the device 1 and is therefore also referred to as the antenna portion 600.

[0022] The electronic circuitry housed in the housing 2 may include a filter network 7 that routes the RF signals (e.g., MICS or BLE) to and from a transceiver 8, as well as therapeutic signals such as stimulation waveforms, between, for example, a corresponding unit 9 (e.g., analog IC) and the electrode. A suitable implementation for this type of network is described in US 10299681 B2, which is hereby incorporated by reference in its entirety.

[0023] Fig. Figure 2 shows a detailed embodiment of the implantable medical device 1 according to the present invention of the Fig. 1 shown species.

[0024] This exemplary design of the terminal block 3 shows a connection of the first electrical electrode line contact 51 of the female connector 5 via the first conductor 61 to the first feedthrough conductor 41 (e.g., pin) comprising the antenna part 600, wherein the second feedthrough contact 42 (e.g., pin) is connected to a second electrode line contact 52 by ordinary external wiring, ie, via the second conductor 62.

[0025] The first section 600 of the first conductor 61, which serves as an antenna, may comprise a plurality of interconnected ring-shaped structures 600a, as shown in the Fig. 2 and Fig. 3 shown.

[0026] In a preferred embodiment, the electrical connection to the first electrical electrode lead contact 51 is characterized by a high impedance at RF frequencies or is configured such that the antenna portion 600 of the first conductor 61 is isolated from variabilities associated with the connected electrode lead (e.g., different electrode lead designs or placements). Separating the antenna portion 600 from the first electrode lead contact 51 is important because each electrode lead connected to the first electrode lead contact 51 can have a variety of designs and lengths, all with different RF characteristics, meaning that without separation, the antenna performance could be compromised by the respective connected electrode lead.One way to separate the antenna portion 600 of the interconnect from the first electrode lead contact 51 is to incorporate an impedance discontinuity 602 between the RF antenna portion 600 and the first electrical electrode lead contact 51, as shown in FIG. Fig. The impedance discontinuity 602 may be in the form of a narrow section of the second portion 601 of the first conductor 61 connecting the RF antenna portion 600 and the first electrical electrode lead contact 51. In particular, this narrow portion 602 is preferably narrow enough to have a resistance in the range of ~ten ohms or more. An additional resistance of ten or twenty ohms will not significantly impair the therapeutic or sensing function of the AIMD. Electrode leads and their electrodes alone may have a resistance of hundreds to over thousands of ohms, but the low resistance can provide significant isolation for the antenna portion 600. In one embodiment, the entire connection, including the antenna portion 600 and the narrow, higher-impedance isolation region 602, is stamped from a sheet of metal.In this embodiment, the higher impedance section is achieved simply by integrating it into the design of the punching tool. In another embodiment, the higher impedance section is obtained by laser cutting into the external wiring (i.e., the first conductor 61) to create a narrow section 602.

[0027] A second technique for separating the antenna portion 600 of the first conductor 61 from the first electrode lead contact 51 is to add inductance to the design. Inductance can result in high impedance at RF frequencies, while having almost no impedance at low frequencies, such as typical AIMD therapy and sensing frequencies. Inductance can be achieved by adding a small spring-like shape (e.g., a coil) with only a few turns to the first conductor. This may be the preferred solution for applications that are very sensitive to any additional electrode lead impedance.

[0028] A schematic of a terminal block design for an additional embodiment of the implantable medical device using the external wiring of two conductors 61, 62, e.g., the first and second conductors 61, 62, is shown in Fig.Here, conductors 61, 62 may have sections 600, 603 that are capacitively coupled to provide a low RF impedance between them, while each electrode lead contact is isolated from each other at lower frequencies for therapy / sensing (via a higher impedance at these lower frequencies). Thus, section 600, 603 may form a high-pass filter.

[0029] The present invention enables a smaller and simplified terminal block for a medical device with easier-to-position conductive components. It also enables improved performance of the RF subsystem due to increased antenna radiation efficiency. Fewer electrical feedthrough connections are required due to the invention. Furthermore, the invention can be used in terminal blocks of medical devices that include or do not include a charging coil.

[0030] Those skilled in the art will appreciate that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings. The disclosed examples and embodiments are presented for illustrative purposes only. Other alternative embodiments may incorporate some or all of the features disclosed herein. Therefore, the intention is to cover all such modifications and alternative embodiments that may fall within the true scope of this invention. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 10299681 B2

[0022]

Claims

[1] Implantable medical device (1) comprising: a housing (2) with an electrical feedthrough (4) comprising at least a first feedthrough conductor (41) and a second feedthrough conductor (42), a terminal block (3) connected to the housing (2), the terminal block (3) comprising a plug socket (5) for an electrode line, which is designed to receive a plug of an electrode line, wherein the plug socket (5) has a first electrical electrode line contact (51) and a second electrical electrode line contact (52), an antenna arranged in the terminal block (3), a first conductor (61) electrically connecting the first electrical contact (51) to the first feedthrough conductor (41), and a second conductor (62) electrically connecting the second electrical contact (52) to the second feedthrough conductor (42), where the antenna is formed by or comprises a first section (600) of the first conductor (61).

Images