Medtronic, Inc.

Other

Michael L Ellingson

Hyun J Yoon

Jonathan D Edmonson

Todd Jon Sheldon

Ben W Herberg

Wade M Demmer

James D Reinke

Paul R Solheim

Matthew J Hoffman

Robert A Betzold

Juliana E Pronovici

Patrick L Parish

Mark K Erickson

Christopher C Stancer

Piotr J Przybyszewski

Alison M Seacord

Lawrence C McClure

Sandy K Wixon

Sean S Josephson

Ben E Herberg

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.

Methods and implantable medical systems that implement exposure modes of therapy that allow for continued operation during exposure to a magnetic disturbance

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.

Automatic selection of parameters of an exposure mode of an implantable medical device

Implantable medical devices automatically switch from a normal mode of operation to an exposure mode of operation and back to the normal mode of operation. The implantable medical devices may utilize hysteresis timers in order to determine if entry and/or exit criteria for the exposure mode are met. The implantable medical devices may utilize additional considerations for entry to the exposure mode such as a confirmation counter or a moving buffer of sensor values. The implantable medical devices may utilize additional considerations for exiting the exposure mode of operation and returning to the normal mode, such as total time in the exposure mode, patient position, and high voltage source charge time in the case of devices with defibrillation capabilities.

Methods and implantable medical devices for automatic entry to an exposure mode of operation upon exposure to a magnetic disturbance

An implantable medical system includes an implantable medical lead including at least one electrode and an implantable medical device (IMD) coupled to the implantable medical lead. The IMD includes a sensing module that obtains electrical signals on the implantable medical lead. The electrical signals on the implantable medical lead include cardiac signals as well as noise-induced signals. The IMD also includes a noise detection module that obtains noise signals independently of the electrical signals on the implantable medical lead. A control module of the IMD adjusts a sensing threshold of the sensing module in response to detecting the noise signals via the noise detection module. In instances in which the amplitude of the noise-induced signal on the lead is too large, the IMD may transition to a noise operating mode specifically designed to accommodate noisy environments.

Implantable medical device with automatic sensing threshold adjustment in noisy environment

An implantable medical device (IMD) configures one or more operating parameters of the IMD based on a type of source of a disruptive energy field to which the IMD is exposed. The disruptive energy field may, in one example, include magnetic and/or radio frequency (RF) fields generated by an MRI scanner. In one aspect, the IMD may distinguish between different types of MRI scanners and select an exposure operating mode tailored to reduce the effects of the particular type of MRI scanner. In another aspect, the IMD may adjust one or more operating parameters that will be used when the IMD returns to a normal operating mode after exposure to the MRI scanner based on the type of MRI scanner to which the IMD is exposed.

Configuring operating parameters of  a medical device based on a type of source of a disruptive energy field

An implantable medical device (IMD) determines an effect of the disruptive energy field and adjusts one or more operating parameters of the IMD based on at least the determined effect. In some instances, the IMD may determine an actual effect of the disruptive energy field, such as a temperature change, impedance change, pacing or sensing threshold change, MRI-induced interference one pacing or sensing, or other actual effect. In other instances, the IMD may determine a predicted effect of the disruptive energy field based on one or more characteristics of the exposure. In any case, the IMD adjusts one or more parameters based on at least the determined effect.

Configuring operating parameters of a medical device based on exposure to a disruptive energy field

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St. Louis Park, MN, United States of America

Michael L Ellingson