Abstract: In some examples, a system may be used for delivering cardiac therapy or cardiac sensing. The system may include an in implantable medical device including a housing configured to be implanted on or within a heart of a patient, a fixation element configured to attach the housing to the heart; and a sensor configured to produce a signal that indicates motion of the implantable medical device. Processing circuitry may be configured to identify one or more impingements between the housing and another structure, such as a tissue of the heart, based on the signal from the sensor and provide an indication of the one or more impingements to a user.

Abstract: A method, system and device for implanting an electrode assembly of an implantable medical device in a patient's heart. Positioning one or more radiopaque markers in a coronary sinus of the patient's heart. Positioning, by using the one or more positioned radiopaque markers as a fluoroscopic visual reference, a distal tip of a delivery catheter within a right atrium of the patient's heart so that a distal opening of a lumen of the catheter is against a septal wall of the heart at a location between the ostium of the coronary sinus and the A-V nodal area of the right atrium, and so that the tip of the catheter is generally directed toward a left ventricle of the patient's heart. Advancing the electrode assembly through the lumen of the catheter and into the septal wall.

Abstract: In some examples, a system can be used for delivering cardiac resynchronization therapy (CRT). The system may include a pacing device configured to be implanted within a patient. The pacing device can include a plurality of electrodes, signal generation circuitry configured to deliver ventricular pacing via the plurality of electrodes, and a sensor configured to produce a signal that indicates mechanical activity of the heart. Processing circuitry can be configured to identify one or more features of a cardiac contraction within the signal, and determine whether the contraction was a fusion beat based on the one or more features.

Abstract: In some examples, a system can be used for delivering cardiac resynchronization therapy (CRT). The system may include a pacing device configured to be implanted within a patient. The pacing device can include a plurality of electrodes, signal generation circuitry configured to deliver ventricular pacing via the plurality of electrodes, and a sensor configured to produce a signal that indicates mechanical activity of the heart. Processing circuitry can be configured to identify one or more features of a cardiac contraction within the signal, and determine whether the contraction was a fusion beat based on the one or more features.

Abstract: An implantable device and associated method for delivering multi-site pacing therapy is disclosed. The device comprises a set of electrodes including a first and second left ventricular electrodes spatially separated from one another and a right ventricular electrode, all coupled to an implantable pulse generator. The processing circuit coupled to the implantable pulse generator, the processing circuit configured to determine whether a prospective heart failure condition has occurred and if so to trigger the pulse generator to switch from a first pacing mode to a second pacing mode, the first pacing mode comprising delivering only a first pacing pulse to a left ventricle (LV) and thereafter delivering an RV pacing pulse to the right ventricular electrode within a single cardiac cycle and the second pacing mode comprising delivering first and a second pacing pulses to the LV and thereafter delivering an RV pacing pulse to the right ventricular electrode within a single cardiac cycle.

Abstract: A pacemaker has a housing and a therapy delivery circuit enclosed by the housing for generating pacing pulses for delivery to a patient's heart. An electrically insulative distal member is coupled directly to the housing and at least one non-tissue piercing cathode electrode is coupled directly to the insulative distal member. A tissue piercing electrode extends away from the housing.

Abstract: A pacemaker has a housing and a therapy delivery circuit enclosed by the housing for generating pacing pulses for delivery to a patient's heart. An electrically insulative distal member is coupled directly to the housing and at least one non-tissue piercing cathode electrode is coupled directly to the insulative distal member. A tissue piercing electrode extends away from the housing.

Abstract: A method, apparatus, or system to identify optimal parameters for programming a cardiac stimulator by a matrix-based decision algorithm using sensor data representing cardiovascular function. The parameters include pacing intervals optimized concurrently to produce the maximum resulting cardiac function.

Abstract: A medical device performs a method for controlling a cardiac pacing therapy. The device determines an inter-atrial conduction time (IACT) and compares the IACT to a threshold. A controller included in the device sets a pacing interval for controlling delivery of pacing pulses to a ventricle to a first ventricular pacing interval that expires after the IACT in response to the IACT being less than the threshold and sets the pacing interval to a second ventricular pacing interval that expires before the IACT in response to the IACT being greater than the threshold.

Abstract: An implantable medical device senses atrial depolarizations having associated refractory periods thereafter and delivers electrical stimulation pulses during the associated refractory periods to stimulate the atrioventricular (AV) node to cause a prolonged conduction time of an atrial depolarization to a ventricular chamber. The device delivers a pacing pulse to a first ventricular chamber during the prolonged conduction time to cause a contraction and associated refractory period of the first ventricular chamber, the first ventricular chamber contraction occurring earlier than a contraction of a second ventricular chamber.

Abstract: A medical device performs a method for controlling a cardiac pacing therapy. The device determines an inter-atrial conduction time (IACT) and compares the IACT to a threshold. A controller included in the device sets a pacing interval for controlling delivery of pacing pulses to a ventricle to a first ventricular pacing interval that expires after the IACT in response to the IACT being less than the threshold and sets the pacing interval to a second ventricular pacing interval that expires before the IACT in response to the IACT being greater than the threshold.

Abstract: A method and medical device for delivering an atrial pacing pulse to an atrial chamber to generate an evoked atrial depolarization, delivering a stimulation pulse to an atrioventricular node during a stimulation window to increase a PR interval of the heart, the stimulation window having a start time corresponding to the delivered atrial pacing pulse so that the stimulation pulse is delivered during a refractory period corresponding to the evoked atrial depolarization, and delivering a ventricular pacing pulse to a first ventricular chamber during the increased PR interval to cause a contraction of the first ventricular chamber to occur prior to a contraction of a second ventricular chamber to increase dyssynchrony between the contraction of the first ventricular chamber and the contraction of the second ventricular chamber.

Abstract: A left-ventricular pacing interval and a right-ventricular pacing interval for timing the delivery of pacing pulses to a left ventricle and a right ventricle of a heart, respectively, may be based an intrinsic conduction time interval between at least one of an atrial sensing event or an atrial pacing event of an atrial chamber of a heart and a ventricular sensing event of a ventricular chamber of the heart. In some examples, the left-ventricular pacing interval is based on the time interval, where the left-ventricular pacing interval is less than the time interval. In some examples, the right-ventricular pacing interval is based on the time interval, where the right-ventricular pacing interval is greater than the left-ventricular pacing interval and less than the time interval.

Abstract: An implantable medical device and associated method control the delivery of extra systolic stimulation by determining a coupling interval, setting an extra systolic interval in response to the coupling interval; and delivering a supraventricular stimulation pulse upon expiration of the extra systolic interval. The supraventricular stimulation pulse evokes a depolarization that is conducted to the ventricles occurring at a ventricular coupling interval relative to a ventricular event.

Abstract: A method and medical device for delivering an atrial pacing pulse to an atrial chamber to generate an evoked atrial depolarization, delivering a stimulation pulse to an atrioventricular node during a stimulation window to increase a PR interval of the heart, the stimulation window having a start time corresponding to the delivered atrial pacing pulse so that the stimulation pulse is delivered during a refractory period corresponding to the evoked atrial depolarization, and delivering a ventricular pacing pulse to a first ventricular chamber during the increased PR interval to cause a contraction of the first ventricular chamber to occur prior to a contraction of a second ventricular chamber to increase dyssynchrony between the contraction of the first ventricular chamber and the contraction of the second ventricular chamber.

Abstract: An implantable medical device senses atrial depolarizations having associated refractory periods thereafter and delivers electrical stimulation pulses during the associated refractory periods to stimulate the atrioventricular (AV) node to cause a prolonged conduction time of an atrial depolarization to a ventricular chamber. The device delivers a pacing pulse to a first ventricular chamber during the prolonged conduction time to cause a contraction and associated refractory period of the first ventricular chamber, the first ventricular chamber contraction occurring earlier than a contraction of a second ventricular chamber.

Abstract: Delivery of fusion pacing therapy to a later depolarizing ventricle (V2) of a heart of a patient may be timed based on the depolarization of the V2 during at least one prior cardiac cycle. In some examples, a V2 pacing pulse is delivered upon the expiration of a pacing interval that begins at detection of an atrial sense or pace event (AP/S). The pacing interval may be substantially equal to the duration of time between an AP/S and a V2 sensing event of at least one prior cardiac cycle decremented by an adjusted pre-excitation interval (PEI). In another example, the V2 pacing pulse is delivered at the expiration of a pacing interval that begins upon detection of a V2 sensing event of a prior cardiac cycle. The pacing interval may be substantially equal to a duration of time at least two subsequent V2 sensing events decremented by the adjusted PEI.

Abstract: A left-ventricular pacing interval and a right-ventricular pacing interval for timing the delivery of pacing pulses to a left ventricle and a right ventricle of a heart, respectively, may be based an intrinsic conduction time interval between at least one of an atrial sensing event or an atrial pacing event of an atrial chamber of a heart and a ventricular sensing event of a ventricular chamber of the heart. In some examples, the left-ventricular pacing interval is based on the time interval, where the left-ventricular pacing interval is less than the time interval. In some examples, the right-ventricular pacing interval is based on the time interval, where the right-ventricular pacing interval is greater than the left-ventricular pacing interval and less than the time interval.

Abstract: A cardiac rhythm sensor positioned on or close to the heart senses electrical or mechanical activity and transmits a cardiac rhythm signal wirelessly to a subcutaneous ICD. Arrhythmia detection and delivery of therapy are performed by the SubQ ICD based upon the cardiac rhythm signal received from the sensor.

Abstract: In some embodiments, an implantable medical device (IMD) system may include one or more of the following elements: (a) an oxygen sensor for measuring oxygen extraction from blood flowing through a coronary sinus of a patient's heart, (b) an oxygen signal generated by the oxygen sensor, (c) an IMD coupled to the oxygen sensor, wherein the IMD is configured to output pacing pulses as a function of the oxygen signal, and (d) an atrial and a ventricular pacing lead coupled to the IMD to deliver the pacing pulses to the patient's heart, wherein the IMD generates the pacing pulses as a function of the oxygen signal, wherein the pacing pulses are adjusted by the IMD as a function of the oxygen signal, wherein the IMD is configured to adjust the pacing pulses to increase oxygen in the blood flow through the coronary sinus.