A shield located within an implantable medical lead may be terminated in various ways at a metal connector. The shield may be terminated by various joints including butt, scarf, lap, or other joints between insulation layers surrounding the lead and an insulation extension. The shield may terminate with a physical and electrical connection to a single metal connector. The shield may terminate with a physical and electrical connection by passing between an overlapping pair of inner and outer metal connectors. The metal connectors may include features such as teeth or threads that penetrate the insulation layers of the lead. The shield may terminate with a physical and electrical connection by exiting a jacket of a lead adjacent to a metal connector and lapping onto the metal connector.

One or more antennas are electrically coupled to one or more switches of an implantable medical device (IMD) in which the one or more switches are additionally electrically coupled to one or more lead wires of an IMD lead. The one or more switches also are electrically coupled to one or more electrodes or electrical circuitry of the IMD's implantable pulse generator (IPG). In response to exposure of the IMD to an energetic electromagnetic field, a voltage signal is induced in the one or more antennas and provided, possibly via one more filters, as a control signal to the one or more switches. Receipt of the control signal by the one or more switches automatically configures the one or more switches into a non-conductive state, thereby electrically isolating the one or more lead wires from the one or more electrodes or the IPG electrical circuitry.

Systems, devices, and methods for electroporation ablation therapy are disclosed, with a protection device for isolating electronic circuitry, devices, and/or other components from a set of electrodes during a cardiac ablation procedure. A system can include a first set of electrodes disposable near cardiac tissue of a heart and a second set of electrodes disposable in contact with patient anatomy. The system can further include a signal generator configured to generate a pulse waveform, where the signal generator coupled to the first set of electrodes and configured to repeatedly deliver the pulse waveform to the first set of electrodes. The system can further include a protection device configured to selectively couple and decouple an electronic device to the second set of electrodes.

Systems, devices, and methods for electroporation ablation therapy are disclosed, with a protection device for isolating electronic circuitry, devices, and/or other components from a set of electrodes during a cardiac ablation procedure. A system can include a first set of electrodes disposable near cardiac tissue of a heart and a second set of electrodes disposable in contact with patient anatomy. The system can further include a signal generator configured to generate a pulse waveform, where the signal generator coupled to the first set of electrodes and configured to repeatedly deliver the pulse waveform to the first set of electrodes. The system can further include a protection device configured to selectively couple and decouple an electronic device to the second set of electrodes.

A medical sensing system (100) includes an elongate interventional device (101) and an adjustable capacitance circuit (102). The elongate interventional device (101) includes a sensor (103) having a capacitance (C.sub.ss). The elongate interventional device (101) also includes a first electrical conductor (104) and a second electrical conductor (105). The first electrical conductor (104) and the second electrical conductor (105) are in electrical contact with the sensor (103) and extend along the elongate interventional device (101). The elongate interventional device (101) also includes i) an electrically conductive shield (106) that overlaps the electrical conductors (104, 105) and/or ii) an electrically conductive shaft (107). The adjustable capacitance circuit (102) provides an adjustable capacitance (C.sub.Adj1, C.sub.Adj2) between at least one of the electrical conductors (104, 105) and i) the electrically conductive shield (106) that overlaps the electrical conductors (104, 105) and/or ii) the electrically conductive shaft (107).

Implantable medical systems enter an exposure mode of operation, either manually via a down linked programming instruction or by automatic detection by the implantable system of exposure to a magnetic disturbance. A controller then determines the appropriate exposure mode by considering various pieces of information including the device type including whether the device has defibrillation capability, pre-exposure mode of therapy including which chambers have been paced, and pre-exposure cardiac activity that is either intrinsic or paced rates. Additional considerations may include determining whether a sensed rate during the exposure mode is physiologic or artificially produced by the magnetic disturbance. When the sensed rate is physiologic, then the controller uses the sensed rate to trigger pacing and otherwise uses asynchronous pacing at a fixed rate.

An implantable medical device comprises a sensing device for sensing a measurement quantity indicative of a presence of an MRI device, a processing device for controlling operation of the implantable medical device and for identifying a presence of an MRI device based on measurement values obtained from the sensing device; and a program memory. An analysis module is configured to store information concerning a multiplicity of events relating to operation of the implantable medical device. The program memory is configured to store at least two program routines for operating the implantable medical device in case of a presence of an MRI device. The processing device is configured, for controlling operation of the implantable medical device in the presence of an MRI device, to select one of said at least two program routines based on a statistical analysis of information concerning a predefined number of events of said multiplicity of events.

Medical devices provide metallic connector enclosures. The metallic connector enclosures may be constructed with relatively thin walls in comparison to polymer connector enclosures to aid in miniaturizing the medical device. The metallic connector enclosures may be constructed with interior surfaces that deviate less from an ideal inner surface shape in comparison to polymer connector enclosures to allow for better concentricity of electrical connectors. The metallic connector enclosures may include a panel that allows access to the cavity of the connector enclosure where set screw blocks, lead connectors, spacers, seals, and the like may be located. Furthermore, the lead connectors within the metallic connector enclosures may be separated from the metallic connector enclosure by being positioned within non-conductive seals that reside within features included in cavity walls of the connector enclosure. Similarly, set screw blocks may be separated from the metallic connector enclosure by non-conductive spacers present within the cavity.

In one example, a system includes telemetry circuitry configured for communication between a medical device and an external device associated with the medical device and processing circuitry. The processing circuitry is configured to determine connection parameters for a connection between the medical device and the external device based on one or more of first information detected by the external device or second information detected by the medical device. The processing circuitry is further configured to output an advertisement for the connection between the medical device and the external device based on the connection parameters and establish the connection between the medical device and the external device according to advertisement.

An implantable medical device (IMD) automatically determines at least a portion of the parameters and, in some instances all of the parameters, of an exposure operating mode based on stored information regarding sensed physiological events or therapy provided over a predetermined period of time. The IMD may configure itself to operate in accordance with the automatically determined parameters of the exposure operating mode in response to detecting a disruptive energy field. Alternatively, the IMD may provide the automatically determined parameters of the exposure operating mode to a physician as suggested or recommended parameters for the exposure operating mode. In other instances, the automatically determined parameters may be compared to parameters received manually via telemetry and, if differences exist or occur, a physician or patient may be notified and/or the manual parameters may be overridden by the automatically determined parameters.