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: Provided is a method, system and/or apparatus for determining prospective heart failure event risk. Acquired from a device memory are a heart failure patient's current and preceding risk assessment periods. Counting detected data observations in the current risk assessment period for a current risk assessment total amount and counting detected data observations in the preceding risk assessment period for a preceding risk assessment period total amount. Associating the current risk assessment and preceding risk assessment total amounts with a lookup table to acquire prospective risk of heart failure (HF) event for the preceding risk assessment period and the current risk assessment period. Employing weighted sums of the prospective risk of the HF event for the preceding risk assessment period and the current risk assessment period to calculate a weighted prospective risk of the HF event for a patient. Displaying on a graphical user interface the weighted prospective risk of the HF event for the patient.

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 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 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: A device and method are described for transmitting tissue conductance communication (TCC) signals. A device may be is configured to establish a transmission window by transmitting a TCC test signal at multiple time points over a transmission test period to a receiving device and detect at least one response to the transmitted TCC test signals performed by the receiving device. The IMD is configured to establish the transmission window based on the at least one detected response so that the transmission window is correlated to a time of relative increased transimpedance between a transmitting electrode vector and receiving electrode vector during the transmission test period.

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 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 implantable medical device has a housing having a proximal end, a distal end and an outer sidewall extending from the proximal end to the distal end. A fixation sheath includes a housing sheath portion extending along the outer sidewall of the housing, and a fixation member portion extending from the housing sheath portion. The housing sheath portion is advanceable from a first position along the outer sidewall of the housing in which the fixation member portion is retracted toward the proximal end of the housing to a second position along the outer sidewall of the housing in which the fixation member portion is deployed to extend away from the housing distal end for anchoring the implantable medical device at an implant site.

Abstract: Various techniques for measuring cardiac cycle length and pressure metrics based on pulmonary artery pressures are described. One example method described includes identifying a point within a derivative signal of a cardiovascular pressure signal without reference to electrical activity of a heart, initiating a time window from the identified point in the derivative signal, identifying a point within the cardiovascular signal within the time window, and determining at least one of a systolic pressure or diastolic pressure based on the identified point.

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: The exemplary systems and methods may monitor one or more signals to be used to assess the hemodynamic status of a patient. The one or more signals may be used to calculate, or determine, a plurality of pulse transit times. The plurality of pulse transit times may be used to determine hemodynamic status values that may be indicative of a patient's aggregate hemodynamic status.

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: Sensing circuitry of an implantable medical device (IMD) system may sense a cardiac signal that varies according to a cardiac cycle of a patient. Processing circuitry of the IMD system may determine a series of consecutive cardiac cycle length metric values based on the sensed cardiac signal, identify a plurality of pairs of the cardiac cycle length metrics, each of the pairs of cardiac cycle length metrics separated by an integer ‘n’ of the cardiac cycle length metrics, and construct a distribution of the pairs of cardiac cycle length metrics based on values of the cardiac cycle length metrics for each of the pairs. The processing circuitry may detect a sleep apnea episode of the patient based on one or more characteristics of the constructed distribution, and control communication circuitry of the IMD system to transmit an indication of the detected sleep apnea episode to the external computing device.

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 medical device system and associated method for use in guiding an acute decompensated heart failure therapy set an optimal fluid status measurement level. A physiological sensor signal sensed by an implantable medical device is used to compute the fluid status measurement. A target rate of change of the fluid status measurement is computed for guiding the therapy.