Abstract: An intracardiac pacemaker system is configured to produce physiological atrial event signals by a sensing circuit of a ventricular intracardiac pacemaker and select a first atrial event input as the physiological atrial event signals. The ventricular intracardiac pacemaker detects atrial events from the selected first atrial event input, determines if input switching criteria are met, and switches from the first atrial event input to a second atrial event input in response to the input switching criteria being met. The second atrial event input includes broadcast atrial event signals produced by a second implantable medical device and received by the ventricular intracardiac pacemaker.

Abstract: 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.

Abstract: 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.

Abstract: An intracardiac ventricular pacemaker having a motion sensor is configured to produce a motion signal including an atrial systolic event and at least one ventricular diastolic event. The pacemaker is configured to set an atrial refractory period, detect a change in a ventricular diastolic event metric and adjust the atrial refractory period in response to detecting the change. The pacemaker sets set an atrioventricular pacing interval in response to detecting the atrial systolic event from the motion signal after expiration of the atrial refractory period.

Abstract: Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous implantable cardioverter defibrillator (SICD) and a leadless pacing device (LPD) are described. For example, the SICD may detect a tachyarrhythmia within a first electrical signal from a heart and determine, based on the tachyarrhythmia, to deliver anti-tachyarrhythmia shock therapy to the patient to treat the detected arrhythmia. The LPD may receive communication from the SICD requesting the LPD deliver anti-tachycardia pacing to the heart and determine, based on a second electrical signal from the heart sensed by the LPD, whether to deliver anti-tachycardia pacing (ATP) to the heart. In this manner, the SICD and LPD may communicate to coordinate ATP and/or cardioversion/defibrillation therapy. In another example, the LPD may be configured to deliver post-shock pacing after detecting delivery of anti-tachyarrhythmia shock therapy.

Abstract: Techniques for minimizing rate of depletion of a non-rechargeable power source, to extend the operational lifetime of an implantable medical device that includes the non-rechargeable power source, by enforcing operational-mode-specific communication protocols whereby inter-device communication between the implantable medical device and another implantable medical device is such that level of power draw from the non-rechargeable power source by the implantable medical device is less than level of power draw from the rechargeable power source by the another implantable medical device for the implantable medical devices to engage in communication with each other.

Abstract: An intracardiac ventricular pacemaker is configured to operate in in a selected one of an atrial-tracking ventricular pacing mode and a non-atrial tracking ventricular pacing mode. A control circuit of the pacemaker determines at least one motion signal metric from the motion signal, compares the at least one motion signal metric to pacing mode switching criteria; and responsive to the pacing mode switching criteria being satisfied, switches from the selected one of the non-atrial tracking pacing mode and the atrial tracking pacing mode to the other one of the non-atrial tracking pacing mode and the atrial tracking pacing mode for controlling ventricular pacing pulses delivered by the pacemaker.

Abstract: A pacemaker having a motion sensor delivers atrial-synchronized ventricular pacing by detecting events from a signal produced by the motion sensor and delivering ventricular pacing pulses at a rate that tracks the rate of the detected events. The pacemaker is configured to confirm atrial tracking of the ventricular pacing pulses by determining if detected events from the motion sensor signal are atrial events. The pacemaker is configured to adjust a control parameter used for detecting events from the motion sensor signal if atrial tracking is not confirmed.

Abstract: An intracardiac ventricular pacemaker is configured to operate in in a selected one of an atrial-tracking ventricular pacing mode and a non-atrial tracking ventricular pacing mode. A control circuit of the pacemaker determines at least one motion signal metric from the motion signal, compares the at least one motion signal metric to pacing mode switching criteria, and, responsive to the pacing mode switching criteria being satisfied, switches from the selected one of the non-atrial tracking pacing mode and the atrial tracking pacing mode to the other one of the non-atrial tracking pacing mode and the atrial tracking pacing mode for controlling ventricular pacing pulses delivered by the pacemaker.

Abstract: An implantable medical device system includes a pacemaker and an implantable cardioverter defibrillator (ICD). The pacemaker is configured to confirm a hemodynamically unstable rhythm based on an activity metric determined from an activity sensor signal after detecting a ventricular tachyarrhythmia and withhold anti-tachycardia pacing (ATP) pulses in response to confirming the hemodynamically unstable rhythm. The pacemaker may deliver ATP when a hemodynamically unstable rhythm is not confirmed based on the activity metric. The ICD is configured to detect the ATP and withhold a shock therapy in response to detecting the ATP in some examples.

Abstract: Techniques for facilitating telemetry between a medical device and an external device are provided. In one example, a medical device includes a classification component and a communication component. The classification component is configured to determine a classification for data generated by the medical device. The classification component is also configured to determine an urgency level for an advertising data packet based on the classification for the data. The communication component is also configured to broadcast the advertising data packet for the medical device at a defined beaconing rate based on the urgency level for the advertising data packet.

Abstract: An implantable medical device system includes a pacemaker and an implantable cardioverter defibrillator (ICD). The pacemaker is configured to confirm a hemodynamically unstable rhythm based on an activity metric determined from an activity sensor signal after detecting a ventricular tachyarrhythmia and withhold anti-tachycardia pacing (ATP) pulses in response to confirming the hemodynamically unstable rhythm. The pacemaker may deliver ATP when a hemodynamically unstable rhythm is not confirmed based on the activity metric. The ICD is configured to detect the ATP and withhold a shock therapy in response to detecting the ATP in some examples.

Abstract: An intracardiac pacemaker system is configured to produce physiological atrial event signals by a sensing circuit of a ventricular intracardiac pacemaker and select a first atrial event input as the physiological atrial event signals. The ventricular intracardiac pacemaker detects atrial events from the selected first atrial event input, determines if input switching criteria are met, and switches from the first atrial event input to a second atrial event input in response to the input switching criteria being met. The second atrial event input includes broadcast atrial event signals produced by a second implantable medical device and received by the ventricular intracardiac pacemaker.

Abstract: An intracardiac ventricular pacemaker is configured to operate in in a selected one of an atrial-tracking ventricular pacing mode and a non-atrial tracking ventricular pacing mode. A control circuit of the pacemaker determines at least one motion signal metric from the motion signal, compares the at least one motion signal metric to pacing mode switching criteria; and responsive to the pacing mode switching criteria being satisfied, switches from the selected one of the non-atrial tracking pacing mode and the atrial tracking pacing mode to the other one of the non-atrial tracking pacing mode and the atrial tracking pacing mode for controlling ventricular pacing pulses delivered by the pacemaker.

Abstract: A medical device system including at least a first implantable medical device and a second implantable medical device is configured to establish by a control module of the first implantable medical device whether the second implantable medical device is present in a patient and self-configure an operating mode of the control module in response to establishing that the second implantable medical device is present.

Abstract: An intracardiac ventricular pacemaker having a motion sensor is configured to produce a motion signal including an atrial systolic event and at least one ventricular diastolic event. The pacemaker is configured to set an atrial refractory period, detect a change in a ventricular diastolic event metric and adjust the atrial refractory period in response to detecting the change. The pacemaker sets set an atrioventricular pacing interval in response to detecting the atrial systolic event from the motion signal after expiration of the atrial refractory period.

Abstract: An implantable rate responsive pacemaker includes a sensor module configured to produce an activity signal correlated to a metabolic demand of a patient and a posture signal correlated to patient posture. The pacemaker further includes a pulse generator configured to generate and deliver pacing pulses to a patient's heart via a pair of electrodes coupled to the pacemaker. A control module is coupled to the pulse generator and the sensor module and is configured to determine a sensor indicated pacing rate from the activity signal, compare the posture signal to verification criteria for confirming an exercising posture of the patient, and withhold an adjustment of a pacing rate to the sensor indicated pacing rate responsive to the verification criteria not being met.

Abstract: An intracardiac ventricular pacemaker having a motion sensor is configured to produce a motion signal including an atrial systolic event and a ventricular diastolic event indicating a passive ventricular filling phase, set a detection threshold to a first amplitude during an expected time interval of the ventricular diastolic event and to a second amplitude lower than the first amplitude after an expected time interval of the ventricular diastolic event. The pacemaker is configured to detect the atrial systolic event in response to the motion signal crossing the detection threshold and set an atrioventricular pacing interval in response to detecting the atrial systolic event.

Abstract: An intracardiac ventricular pacemaker is configured to detect a ventricular diastolic event from a motion signal received by a pacemaker control circuit from a motion sensor. The control circuit starts an atrial refractory period having an expiration time set based on a time of the detection of the ventricular diastolic event. The control circuit detects an atrial systolic event from the motion signal after expiration of the atrial refractory period and controls a pulse generator of the pacemaker to deliver a pacing pulse to a ventricle of a patient's heart at a first atrioventricular pacing time interval after the atrial systolic event detection.

Abstract: A device includes a signal generator module, a processing module, and a housing. The signal generator module is configured to deliver pacing pulses to an atrium. The processing module is configured to detect a ventricular activation event and determine a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event. The processing module is further configured to schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval and control the signal generator module to deliver the pacing pulse at the scheduled time. The housing is configured for implantation within the atrium. The housing encloses the stimulation generator and the processing module.