Abstract: Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), subcutaneous implantable cardioverter defibrillators (SICD), transvenous implantable cardioverter defibrillators, neuro-stimulators (NS), implantable monitors (IM), may be configured to communicate with each other. In some cases, a first IMD may transmit instructions to a second IMD. In order to improve the chances of a successfully received transmission, the first IMD may transmit the instructions several times during a particular time frame, such as during a single heartbeat. If the second IMD receives the message more than once, the second IMD recognizes that the messages were redundant and acts accordingly.

Abstract: An implantable cardiac monitor (ICM) may be configured to be deployed subcutaneous, submuscular, or substernal at a position that enables the ICM to detect cardiac activity. In some cases, the ICM includes a housing that includes a body portion and a tail portion. A first electrode may be disposed adjacent a first end of the body portion, a second electrode may be disposed adjacent a second end of the body portion and a third electrode may be disposed adjacent a tail end of the tail portion. A controller may be disposed within the housing and may be operably coupled to the first electrode, the second electrode and the third electrode. The controller may be configured to select a pair of the first electrode, the second electrode and the third electrode to use for sensing cardiac electrical activity and to communicate information about the sensed activity to a second medical device.

Abstract: Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), subcutaneous implantable cardioverter defibrillators (SICD), transvenous implantable cardioverter defibrillators, neuro-stimulators (NS), implantable monitors (IM), may be configured to communicate with each other. In some cases, a first IMD may transmit instructions to a second IMD. In order to improve the chances of a successfully received transmission, the first IMD may transmit the instructions several times during a particular time frame, such as during a single heartbeat. If the second IMD receives the message more than once, the second IMD recognizes that the messages were redundant and acts accordingly.

Abstract: Systems and methods for communicating between medical devices. In one example, an implantable medical device comprising may comprise one or more electrodes and a controller coupled to the electrodes. The controller may be configured to receive a first communication pulse at a first communication pulse time and a second communication pulse at a second communication pulse time via the one or more electrodes. The controller may further be configured to identify one of three or more symbols based at least in part on the time difference between the first communication pulse time and the second communication pulse time.

Abstract: Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), subcutaneous implantable cardioverter defibrillators (SICD), transvenous implantable cardioverter defibrillators, neuro-stimulators (NS), implantable monitors (IM), may be configured to communicate with each other. In some cases, a first IMD may transmit instructions to a second IMD. In order to improve the chances of a successfully received transmission, the first IMD may transmit the instructions several times during a particular time frame, such as during a single heartbeat. If the second IMD receives the message more than once, the second IMD recognizes that the messages were redundant and acts accordingly.

Abstract: Systems, devices, and methods for pacing a heart of a patient are disclosed. A device may include a leadless cardiac pacemaker (LCP) that includes a power supply, a pair of electrodes, and a controller operably connected to the electrodes and the power supply. The controller may identify a capture threshold by setting a pace amplitude at a power supply voltage of the power supply and deliver pacing stimulation pulses with different pulse widths to identify the capture threshold. The LCP may then deliver pacing stimulation pulses based, at least in part, on a pulse amplitude and pulse width associated with the capture threshold, and also adding a capture margin. In some cases, the pulse amplitude may change over time and the LCP may adjust a pulse width along a strength-duration curve to account for the pulse amplitude change and maintain a capture threshold and capture margin.

Abstract: An implantable medical device (IMD) may be deployed within a patient's right atrium at a location near a right atrial appendage of the patient's heart in order to pace the patient's heart and/or to sense electrical activity within the patient's heart. In some cases, an IMD may be implanted within the right atrial appendage. The IMD may include an expandable anchoring mechanism configured to secure the IMD in place.

Abstract: An implantable medical device (IMD) may include a sensor for providing a sensor output signal and a sense channel configured to receive the sensor output signal from the sensor. The sense channel may be configured to process the sensor output signal and output a sense channel output signal. The sense channel may have an adjustable performance level, wherein for a higher performance level the sense channel consumes more power than for a lower performance level. A controller may be configured to adjust the performance level of the sense channel to achieve more performance and more power consumption when a higher degree of sense channel performance is desired and to achieve less performance and less power consumption when a higher degree of performance is not desired.

Abstract: Systems, devices, and methods for pacing a heart of a patient are disclosed. An illustrative method may include determining a motion level of the patient using a motion sensor of an implantable medical device secured relative to a patient's heart, and setting a pacing rate based at least in part on the patient's motion level. The patient's motion level may be determined by, for example, comparing the motion level sensed by the motion sensor during a current heart beat to a motion level associated with one or more previous heart beats. Noise may occur in the motion level measurements during those heart beats that transition between an intrinsically initiated heart beat and pace initiated heart beat. Various techniques may be applied to the motion level measurements to help reduce the effect of such noise.

Abstract: Systems and methods for conducted communication are described. In one embodiment, a method for communicating with implantable medical devices may comprise sensing, by a first medical device, a noise signal delivered into a patient's body by a second medical device and delivering, by the first medical device, a cancelling signal into the patient's body. In at least some additional embodiments the method may further comprise, while delivering the cancelling signal into the patient's body, delivering a conducted communication signal into the patient's body for reception by a second medical device.

Abstract: Systems, devices, and methods for adjusting functionality of an implantable medical device based on posture are disclosed. In some instances, a method for operating a leadless cardiac pacemaker implanted into a patient, where the patient has two or more predefined behavioral states, may include detecting a change in the behavioral state of the patient, and in response, changing a sampling rate of a sensor signal generated by a sensor of the leadless cardiac pacemaker. In some embodiments, the method may further include using the sampled sensor signal to determine an updated pacing rate of the leadless cardiac pacemaker and providing pacing to the patient at the updated pacing rate.

Abstract: Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), subcutaneous implantable cardioverter defibrillators (SICD), transvenous implantable cardioverter defibrillators, neuro-stimulators (NS), implantable monitors (IM), may be configured to communicate with each other. In some cases, a first IMD may transmit instructions to a second IMD. In order to improve the chances of a successfully received transmission, the first IMD may transmit the instructions several times during a particular time frame, such as during a single heartbeat. If the second IMD receives the message more than once, the second IMD recognizes that the messages were redundant and acts accordingly.

Abstract: Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), neuro-stimulators (NS), and/or implantable monitors (IM), may be configured to communicate using more than one mode of communication and/or more than one communication vector. In some cases, the implantable medical device may be configured to switch between communication modes, vectors, and/or communication paths, which may help improve communication reliability and/or communication speed between devices.

Abstract: Systems, devices, and methods for pacing a heart of a patient are disclosed. A device may include a leadless cardiac pacemaker (LCP) that includes a power supply, a pair of electrodes, and a controller operably connected to the electrodes and the power supply. The controller may identify a capture threshold by setting a pace amplitude at a power supply voltage of the power supply and deliver pacing stimulation pulses with different pulse widths to identify the capture threshold. The LCP may then deliver pacing stimulation pulses based, at least in part, on a pulse amplitude and pulse width associated with the capture threshold, and also adding a capture margin. In some cases, the pulse amplitude may change over time and the LCP may adjust a pulse width along a strength-duration curve to account for the pulse amplitude change and maintain a capture threshold and capture margin.

Abstract: An implantable medical device (IMD) may be deployed within a patient's right atrium at a location near a right atrial appendage of the patient's heart in order to pace the patient's heart and/or to sense electrical activity within the patient's heart. In some cases, an IMD may be implanted within the right atrial appendage. The IMD may include an expandable anchoring mechanism configured to secure the IMD in place.

Abstract: An implantable medical device (IMD) may include a sensor for providing a sensor output signal and a sense channel configured to receive the sensor output signal from the sensor. The sense channel may be configured to process the sensor output signal and output a sense channel output signal. The sense channel may have an adjustable performance level, wherein for a higher performance level the sense channel consumes more power than for a lower performance level. A controller may be configured to adjust the performance level of the sense channel to achieve more performance and more power consumption when a higher degree of sense channel performance is desired and to achieve less performance and less power consumption when a higher degree of performance is not desired.

Abstract: Systems, devices, and methods for pacing a heart of a patient are disclosed. An illustrative method may include determining a motion level of the patient using a motion sensor of an implantable medical device secured relative to a patient's heart, and setting a pacing rate based at least in part on the patient's motion level. The patient's motion level may be determined by, for example, comparing the motion level sensed by the motion sensor during a current heart beat to a motion level associated with one or more previous heart beats. Noise may occur in the motion level measurements during those heart beats that transition between an intrinsically initiated heart beat and pace initiated heart beat. Various techniques may be applied to the motion level measurements to help reduce the effect of such noise.

Abstract: Systems and methods for communicating between medical devices. In one example, an implantable medical device comprising may comprise one or more electrodes and a controller coupled to the electrodes. The controller may be configured to receive a first communication pulse at a first communication pulse time and a second communication pulse at a second communication pulse time via the one or more electrodes. The controller may further be configured to identify one of three or more symbols based at least in part on the time difference between the first communication pulse time and the second communication pulse time.

Abstract: An implantable cardiac monitor (ICM) may be configured to be deployed subcutaneous, submuscular, or substernal at a position that enables the ICM to detect cardiac activity. In some cases, the ICM includes a housing that includes a body portion and a tail portion. A first electrode may be disposed adjacent a first end of the body portion, a second electrode may be disposed adjacent a second end of the body portion and a third electrode may be disposed adjacent a tail end of the tail portion. A controller may be disposed within the housing and may be operably coupled to the first electrode, the second electrode and the third electrode. The controller may be configured to select a pair of the first electrode, the second electrode and the third electrode to use for sensing cardiac electrical activity and to communicate information about the sensed activity to a second medical device.

Abstract: Systems and methods for conducted communication are described. In one embodiment, a method of communicating with a medical device implanted within a patient comprises receiving, at a medical device via electrodes connected to the patient, a conducted communication signal, wherein the conducted communication signal comprises a signal component and a noise component. The method may further comprise adjusting, by the medical device, a receive threshold based at least in part on an amplitude of the received conducted communication signal so as to reduce an amplitude of the noise component of the conducted communication signal.