Abstract: An implantable system detecting electrical signals of a human or animal heart includes a processor, a memory unit, a first detection unit for atrial activity, a second detection unit for right ventricular activity and a third detection unit for left ventricular activity. The system automatically performs steps at regular intervals including detecting an intrinsic right atrial activity using the first detection unit; detecting an intrinsic right ventricular activity using the second detection unit; determining a time between the intrinsic right atrial activity and the intrinsic right ventricular activity, and storing this time as atrioventricular conduction time.

Abstract: A system and method have at least one implantable lead comprising a right ventricular (RV) electrode and one or more left ventricular (LV) electrodes, at least one processor, and a memory coupled to the at least one processor. The memory stores program instructions.

Abstract: A ventricularly implantable medical device that includes a sensing module that is configured to detect an atrial fiducial and identify an atrial contraction based at least on part on the detected atrial fiducial. Control circuitry in the implantable medical device is configured to deliver a ventricular pacing therapy to a patient's heart based at least in part on the identified atrial contraction, and can automatically switch or revert the ventricular pacing therapies on the fly.

Abstract: Methods and systems are provided herein for pacing a HIS bundle of a patient heart using an implantable medical device (IMD). The methods and systems obtain cardiac activity (CA) signals over a HIS sensing channel, the HIS sensing channel utilizing a HIS electrode; identify at least one of a P-wave duration (PWD), an intrinsic atrial-HIS (AH) delay, or an intrinsic atrial conduction delay (IACD); calculate an atrial oversensing avoidance (AOA) window based on at least one of the PWD, AH delay or IACD; analyze the CA signals, obtained over the HIS sensing channel during the AOA window, for an atrial activity (AA) component; based on the analyzing operation, adjust a ventricular event (VE) sensitivity profile utilized by the HIS sensing channel; monitor the CA signals, obtained over the HIS sensing channel during an alert window based on the VE sensitivity profile, for a ventricular component indicative of a ventricular event; and manage HIS bundle pacing based on the ventricular event.

Abstract: Embodiments described herein relate to implantable medical devices (IMDs) and methods for use therewith. Such a method includes using an accelerometer of an IMD (e.g., a leadless pacemaker) to produce one or more accelerometer outputs indicative of the orientation of the IMD. The method can also include controlling communication pulse parameter(s) of one or more communication pulses (produced by pulse generator(s)) based on accelerator output(s) indicative of the orientation of the IMD. The communication pulse parameter(s) that is/are controlled can be, e.g., communication pulse amplitude, communication pulse width, communication pulse timing, and/or communication pulse morphology. Such embodiments can be used to improve conductive communications between IMDs whose orientation relative to one another may change over time, e.g., due to changes in posture and/or due to cardiac motion over a cardiac cycle.

Abstract: An implantable medical device system receives a cardiac electrical signal produced by a patient's heart and comprising atrial P-waves and delivers a His bundle pacing pulse to the patient's heart via a His pacing electrode vector. The system determines a timing of a sensed atrial P-wave relative to the His bundle pacing pulse and determines a type of capture of the His bundle pacing pulse in response to the determined timing of the atrial P-wave.

Abstract: A leadless pacemaker device configured to provide for an intra-cardiac pacing, including: processing circuitry configured to generate ventricular pacing signals for stimulating ventricular activity, and a reception device for receiving a sensing signal indicative of an atrial activity, wherein the processing circuitry is configured to detect an atrial event derived from said sensing signal, wherein the atrial event is a valid atrial sense event, where a series of atrial events lie within a range for a normal atrial rate, and/or when the atrial rate variability is within a certain range indicating a regular atrial rhythm, wherein in case a valid atrial sense event is detected, the processing circuitry is further configured to: determine ventricular pacing events according to atrial events, calculate ventricular-atrial time delays, determine a correction value based a measured time delay and the calculated time delay, and adjust the ventricular pacing timing based on the correction value.

Abstract: An intracardiac ventricular pacemaker includes a pulse generator for delivering ventricular pacing pulses, an impedance sensing circuit, and a control circuit in communication with the pulse generator and the impedance sensing circuit. The pacemaker is configured to produce an intraventricular impedance signal, detect an atrial systolic event using the intraventricular impedance signal, set an atrioventricular pacing interval in response to detecting the atrial systolic event, and deliver a ventricular pacing pulse in response to the atrioventricular pacing interval expiring.

Abstract: Computer implemented methods and systems are provided for automatically determining capture thresholds for an implantable medical device equipped for cardiac stimulus pacing using a multi-pole left ventricular (LV) lead. The methods and systems measures a base capture threshold for a base pacing vector utilizing stimulation pulses varied over at least a portion of an outer test range. The base pacing vector is defined by a first LV electrode provided on the LV lead and a second electrode located remote from an LV chamber. The methods and systems designate a secondary pacing vector that includes the first LV electrode and a neighbor LV electrode provided on the LV lead. The methods and systems further define an inner test range having secondary limits based on the base capture threshold, wherein at least one of the limits for the inner test range differs from a corresponding limit for the outer test range.

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: Method and system for determining an atrial contraction timing fiducial in a leadless cardiac pacemaker system is disclosed. An electrical cardiac signal associated with an atrial contraction of the patient's heart and a mechanical response to the atrial contraction of a patient's heart are used to determine an atrial contraction timing fiducial. A ventricle pacing pulse may then be generated an A-V delay after the atrial contraction timing fiducial.

Abstract: An apparatus comprises an input configured to receive electrocardiogram (ECG) data detected by a patient monitoring device, the ECG data containing a physiologic signal and one or more segments of noise within the ECG data. A scrubber comprises a plurality of scrubbing modules each configured to process the ECG data and noise in a manner differing from other scrubbing modules. The scrubber is configured to filter the one or more noise segments that overlap with the physiologic signal, and consolidate the ECG data to eliminate the one or more noise segments that are non-overlapping with the physiologic signal. An output is configured to output scrubbed ECG data.

Abstract: The present invention relates to the field of medical devices and discloses an implantable medical device for treating arrhythmia. The implantable medical device includes a control unit and, each coupled to the control unit, a sense amplifier, a first switch and a second switch. The sense amplifier includes a polarity selection module, an amplification unit and a filtering unit, which are sequentially connected. The first switch is disposed within the polarity selection module, and the second switch within the filtering unit. The control unit is configured to shield the sense amplifier from interference from a pacing pulse signal by providing multi-stage on/off control over the first and second switches according to a pacing period and a discharging period in a pacing interval.

Abstract: An implantable system includes a first leadless pacemaker (LP1) implanted in or on a first chamber of a heart and a second leadless pacemaker (LP2) implanted in or on a second chamber of the heart. The LP1 is configured to time delivery of one or more pacing pulses delivered to the first chamber of the heart based on timing of cardiac activity associated with the second chamber of the heart detected by the LP1 itself. The LP1 is also configured to transmit implant-to-implant (i2i) messages to the LP2. The LP2 is configured to time delivery of one or more pacing pulses delivered to the second chamber of the heart based on timing of cardiac activity associated with the second chamber of the heart as determined based on one or more i2i messages received by the LP2 from the LP1.

Abstract: The disclosure relates to a device including a plurality of electrodes for stimulation of both ventricles with application of an atrioventricular delay and of an interventricular delay, a processor configured to multidimensionally measure an interventricular conduction delay, and monitor the evolution of a patient's condition. For the multidimensional measurement of the interventricular conduction delay, the device produces stimulation of one of the ventricles and collects, in the other ventricle, two endocardial electrogram signals on separate respective channels, giving two respective temporal components. Both temporal components are combined in one single parametric 2D characteristic representative of the cardiac cycle, and a comparison is made with reference descriptors for deriving an index representative of the evolution of the patient's condition.

Abstract: A ventricularly implantable medical device that includes a sensing module that is configured to identify a search window of time within a cardiac cycle to search for an atrial artifact. Control circuitry in the ventricular implantable medical device is configured to deliver a ventricular pacing therapy to a patient's heart, wherein the ventricular pacing therapy is time dependent, at least in part, on an atrial event identified in the search window of time.

Abstract: An extra-cardiovascular implantable cardioverter defibrillator (ICD) system receives a cardiac electrical signal by an electrical sensing circuit via an extra-cardiovascular sensing electrode vector and senses cardiac events from the cardiac electrical signal. The ICD system detects tachycardia from the cardiac electrical signal and determines a tachycardia cycle length from the cardiac electrical signal. The ICD system determines an ATP interval based on the tachycardia cycle length and sets an extended ATP interval that is longer than the ATP interval. The ICD delivers ATP pulses to a patient's heart via an extra-cardiovascular pacing electrode vector different than the sensing electrode vector. The ATP pulses include a leading ATP pulse delivered at the extended ATP interval after a cardiac event is sensed from the cardiac electrical signal and a second ATP pulse delivered at the ATP interval following the leading ATP pulse.

Abstract: Embodiments described herein generally relate to methods and systems for monitoring and responding to changes in a patient's physiologic status. A method includes sensing pulmonary arterial pressure (PAP) and thoracic impedance of a patient at rest. The method also includes detecting, based on the sensed PAP, whenever the patient's PAP at rest is outside an acceptable range of PAP measures for the patient at rest, and detecting, based on the sensed thoracic impedance, whenever the patient's respiration at rest is outside an acceptable range of respiration measures for the patient at rest. Various different actions are triggered depending upon whether the patient's PAP at rest is outside the acceptable range of PAP measures for the patient at rest, and whether the patient's respiration at rest is within the acceptable range of respiration measures for the patient at rest. Other embodiments relate to similar methods performed at other levels of exertion.

Abstract: Methods, systems and devices for providing cardiac resynchronization therapy (CRT) to a patient using a leadless cardiac pacemaker (LCP) implanted in or proximate the left ventricle of a patient. A setup phase is used to establish parameters in the therapy delivery. In operation, the method and/or device will sense at least one non-paced cardiac cycle to determine a native R-R interval, and then delivers a synchronization pace at an interval less than the native R-R interval followed by a plurality of pace therapies delivered at the R-R interval or a modification thereof.

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 medical device is configured to control a therapy module to couple a capacitor array comprising a plurality of capacitors to a plurality of extra-cardiovascular electrodes and control the therapy module to deliver a composite pacing pulse to a patient's heart via the plurality of extra-cardiovascular electrodes by sequentially discharging at least a portion of the plurality capacitors to produce a series of at least two individual pulses that define the composite pacing pulse.

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: A therapeutic window for at least one electrode of a medical system may be determined based on a volume of tissue expected to be activated (“VTA”) by electrical stimulation delivered by the at least one electrode. In some examples, a processor determines the therapeutic window for a particular electrode by at least determining an efficacy threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the efficacy threshold, and determining an adverse-effects threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the adverse-effects threshold.

Abstract: A medical device for treating cardiac arrhythmia includes a microprocessor. A MCU configures the medical device to operate in a modified DVI (R) mode in which: when receiving a signal indicating the sensing of an atrial event, the MCU sets a PANP interval and sends to a time control unit a signal; if a scheduled post-ventricular atrial escaping interval is to end at a time not within the PANP internal, the MCU sends respective signals to a pacing control/generation unit and the time control unit to dictate the pacing control/generation unit and control a second timing unit to use a PAVI as a next ventricular escape interval; and if the scheduled post-ventricular atrial escaping interval is to end within the PANP interval, the MCU sends a signal to the time control unit, controlling the second timing unit to use the PAVI as the next ventricular escape interval.

Abstract: The disclosure relates to a device including a plurality of electrodes for stimulation of both ventricles with application of an atrioventricular delay and of an interventricular delay, a processor configured to multidimensionally measure an interventricular conduction delay, and monitor the evolution of a patient's condition. For the multidimensional measurement of the interventricular conduction delay, the device produces stimulation of one of the ventricles and collects, in the other ventricle, two endocardial electrogram signals on separate respective channels, giving two respective temporal components. Both temporal components are combined in one single parametric 2D characteristic representative of the cardiac cycle, and a comparison is made with reference descriptors for deriving an index representative of the evolution of the patient's condition.

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 ventricular electrode and a second ventricular electrode, spatially separated from one another and all coupled to an implantable pulse generator. The device comprises a processor configured for selecting a first cathode and a first anode from the set of electrodes to form a first pacing vector at a first pacing site along a heart chamber and selecting a second cathode and a second anode from the set of electrodes to form a second pacing vector at a second pacing site along the same heart chamber. The pulse generator is configured to deliver first pacing pulses to the first pacing vector and delivering second pacing pulses to the second pacing vector. The pulse generator generates a recharging current for recharging a first coupling capacitor over a first recharge time period in response to the first pacing pulses.

Abstract: Systems and methods for selecting one or more sites at or within at least one heart chamber for cardiac stimulation are disclosed. The system can include a physiologic sensor circuit to sense physiologic signals at two or more candidate stimulation sites. The system can generate respective activation timing indicators corresponding to the two or more candidate stimulation sites, and detect MI indicators indicating the presence of, or spatial proximity of each of the two or more candidate stimulation sites to a MI tissue. The system can use the activation timing indicators and the MI indicators to select at least one target stimulation site or to determine an electrostimulation vector. The system can display the selected target stimulation site to a user, or deliver electrostimulation to the patient at the target stimulation site or according to the determined electrostimulation vector.

Abstract: Systems, devices and methods for using environmental data to manage health care are disclosed. One aspect is an advanced patient management system. In various embodiments, the system includes at least one implantable medical device (IMD) to acquire at least one IMD parameter indicative of patient wellness, means to acquire at least one environmental parameter from at least one external source, and means to correlate the at least one parameter indicative of patient wellness and the at least one environmental parameter to assist with patient health care decisions. Other aspects and embodiments are provided herein.

Abstract: A therapeutic window for at least one electrode of a medical system may be determined based on a volume of tissue expected to be activated (“VTA”) by electrical stimulation delivered by the at least one electrode. In some examples, a processor determines the therapeutic window for a particular electrode by at least determining an efficacy threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the efficacy threshold, and determining an adverse-effects threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the adverse-effects threshold.

Abstract: An intracardiac ventricular pacemaker is configured to detect an atrial mechanical event from a motion sensor signal received by an atrial event detector circuit of the pacemaker. The motion sensor signal is responsive the motion of blood flowing in the ventricle. A pacing pulse is scheduled at an expiration of a pacing interval set by a pace timing circuit in response to detecting the atrial mechanical event. An atrial-synchronized ventricular pacing pulse is delivered upon expiration of the pacing interval.

Abstract: The disclosure relates to a device including a plurality of electrodes for stimulation of both ventricles with application of an atrioventricular delay and of an interventricular delay, a processor configured to multidimensionally measure an interventricular conduction delay, and monitor the evolution of a patient's condition. For the multidimensional measurement of the interventricular conduction delay, the device produces stimulation of one of the ventricles and collects, in the other ventricle, two endocardial electrogram signals on separate respective channels, giving two respective temporal components. Both temporal components are combined in one single parametric 2D characteristic representative of the cardiac cycle, and a comparison is made with reference descriptors for deriving an index representative of the evolution of the patient's condition.

Abstract: In general, the disclosure describes techniques for predicting the occurrence of an arrhythmia based on an indication of heart rate turbulence. An example method comprises sensing a parameter indicative of heart rate turbulence, measuring heart rate turbulence based on the sensed parameter, and predicting an occurrence of an arrhythmia based on the measured heart rate turbulence.

Abstract: A therapeutic window for at least one electrode of a medical system may be determined based on a volume of tissue expected to be activated (“VTA”) by electrical stimulation delivered by the at least one electrode. In some examples, a processor determines the therapeutic window for a particular electrode by at least determining an efficacy threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the efficacy threshold, and determining an adverse-effects threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the adverse-effects threshold.

Abstract: The disclosure relates to a device including a plurality of electrodes for stimulation of both ventricles with application of an atrioventricular delay and of an interventricular delay, a processor configured to multidimensionally measure an interventricular conduction delay, and monitor the evolution of a patient's condition. For the multidimensional measurement of the interventricular conduction delay, the device produces stimulation of one of the ventricles and collects, in the other ventricle, two endocardial electrogram signals on separate respective channels, giving two respective temporal components. Both temporal components are combined in one single parametric 2D characteristic representative of the cardiac cycle, and a comparison is made with reference descriptors for deriving an index representative of the evolution of the patient's condition.

Abstract: An implantable medical device system including an atrial pacemaker and a ventricular pacemaker is configured to deliver dual chamber pacing in the presence of atrioventricular block. In response to detecting the AV block, the atrial pacemaker may establish a limited number of selectable pacing rates. The atrial pacemaker selects a rate from the limited number of selectable pacing rates and adjusts the atrial pacing rate to the selected rate. The ventricular pacemaker is configured to establish a ventricular pacing rate that is equivalent to the selected rate in response to detecting the AV block. Other examples are described herein.

Abstract: Methods, devices and systems are provided for selecting one or more left ventricular multi-electrode pacing site(s). The methods, devices and systems measure arrival times of LV activation events for corresponding LV sensing sites, where the arrival times each correspond to a conduction time from an intrinsic ventricular event or delivery of a pacing pulse until sensing of the corresponding LV activation event. Site-to-site (STS) relative delays are calculated as differences between the arrival times associated with adjacent LV sensing sites. The STS relative delays represent STS arrival delays for corresponding combinations of the adjacent LV sensing sites. An LV electrode combination is identified that is associated with at least one of the STS relative delays that satisfy selection criteria, where the LV electrode combination corresponds to a target tissue region exhibiting a select degree of non-uniformity.

Abstract: A method and an implantable medical system for monitoring respiratory parameters, and a corresponding computer program and a corresponding computer-readable storage medium which can be used in particular for monitoring, especially for remote monitoring of the health condition of a patient with cardiac insufficiency that provides an improved method for determining the functional capacity of the cardiovascular system with consideration for stress.

Abstract: An implantable cardiac rhythm system includes a first implantable medical device configured to detect a first heartbeat from a first location, and a second implantable medical device configured to detect the first heart beat of the patient from a second location. The second implantable medical device, upon detecting the first heart beat, may communicate an indication of the detected first heart beat to the first implantable medical device, and in response, the first implantable medical device may institute a blanking period having a blanking period duration such that a T-wave of the detected first heart beat is blanked out by the first implantable medical device so as to not be interpreted as a subsequent second heart beat. In some instances, the first implantable medical device is an SICD and the second implantable medical device is a LCP.

Abstract: A therapeutic window for at least one electrode of a medical system may be determined based on a volume of tissue expected to be activated (“VTA”) by electrical stimulation delivered by the at least one electrode. In some examples, a processor determines the therapeutic window for a particular electrode by at least determining an efficacy threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the efficacy threshold, and determining an adverse-effects threshold based on the VTA expected to result from the delivery of electrical stimulation according to a set of electrical stimulation parameter values including the stimulation parameter at the adverse-effects threshold.

Abstract: A method and apparatus for treatment of hypertension and heart failure by increasing vagal tone and secretion of endogenous atrial hormones by excitory pacing of the heart atria. Atrial pacing is done during the ventricular refractory period resulting in atrial contraction against closed AV valves, and atrial contraction rate that is higher than the ventricular contraction rate. Pacing results in the increased atrial wall stress. An implantable device is used to monitor ECG and pace the atria in a nonphysiologic manner.

Abstract: A method for operating a pacemaker comprises the procedures of building a database of a cardiac cycle of a patient suffering from bundle branch block and artificially pacing a ventricle of the patient using the pacemaker according to anticipative atrioventricular (AV) delays in the database which are based on measured P-P intervals in the database.

Abstract: Method and system for non-linear modeling of physiological behavior, such as R-R intervals, in implantable devices, such as a rate responsive pacemakers, comprising a comprehensive modeling and optimization methodology based on fractional calculus and constrained finite horizon optimal control theory that allows for allows for fine-grain optimization of pacemaker response to heart rate variations; and the theoretical basis on which a hardware implementation of the fractional optimal controller that can respond to changes in the heart rate dynamics. Present invention describes a fractal approach to pacemaker control based on the constrained finite horizon optimal control problem. This is achieved by modeling the heart rate dynamics via fractional differential equations. Also, by using calculus of variations, the invention describes how the constrained finite horizon optimal control problem can be reduced to solving a linear system of equations.

Abstract: An implantable medical system is configured to coordinate ventricular pacing with intrinsic depolarizations of another chamber. The implantable medical system includes a leadless pacing device implanted on or within the ventricle. Another implantable medical device is configured to sense an intrinsic depolarization the other chamber of the heart of the patient, and in response to the intrinsic depolarization of the other chamber, deliver an electrical pulse. The leadless pacing device is configured to detect the electrical pulse delivered by the other implantable medical device and, in response to detecting the electrical pulse delivered by the other implantable medical device, deliver a pacing pulse to the ventricle via at least a first electrode in coordination with the intrinsic depolarization of the other 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 medical device and associated method classify candidate pacing electrode sites for delivering pacing pulses to a patient's heart. A first morphology template is established and stored in memory of the device. A processor is configured to determine a cardiac signal morphology in response to delivering pacing pulses at a candidate pacing site in a first heart chamber. The processor compares the determined cardiac signal morphology to the first morphology template. The pacing site in the first heart chamber is classified in response to the comparing of the determined cardiac signal morphology and the first morphology template.

Abstract: Therapeutic implantable cardiac pacing systems incorporating improved electrocardiographic acquisition systems for the purpose of ventricular pacing during wide QRS complexes of intrinsic origin, in order to narrow the QRS complex in patients where QRS narrowing is achievable and improving ventricular function in all patients with wide QRS complexes including those where QRS shortening does not result. These pacing systems are employed to increase coronary artery flow and electrode position is employed to improve ventricular motion in the treatment of functional ventricular abnormalities caused by wide QRS complexes.

Abstract: A non-invasive bodily-attached ambulatory medical monitoring and treatment device with pacing is provided. The noninvasive ambulatory pacing device includes a battery, at least one therapy electrode coupled to the battery, a memory storing information indicative of a patient's cardiac activity, and at least one processor coupled to the memory and the at least one therapy electrode. The at least one processor is configured to identify a cardiac arrhythmia within the information and execute at least one pacing routine to treat the identified cardiac arrhythmia.

Abstract: Techniques are provided for use with implantable medical devices such as pacemakers for optimizing interventricular (VV) pacing delays for use with cardiac resynchronization therapy (CRT). In one example, ventricular electrical depolarization events are detected within a patient in whom the device is implanted. The onset of isovolumic ventricular mechanical contraction is also detected based on cardiomechanical signals detected by the device, such as cardiogenic impedance (Z) signals, S1 heart sounds or left atrial pressure (LAP) signals. Then, an electromechanical time delay (T_QtoVC) between ventricular electrical depolarization and the onset of isovolumic ventricular mechanical contraction is determined. VV pacing delays are set to minimize the time delay to the onset of isovolumic ventricular mechanical contraction. Various techniques for identifying the onset of isovolumic ventricular contraction based on Z, S1 or LAP or other cardiomechanical signals are described.

Abstract: Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous device (e.g. subcutaneous implantable (SD)) and a leadless pacing device (LPD) are described. In one or more embodiments, a computer-implemented method includes sensing a first electrical signal from a heart of a patient through a SD. The first signal is stored into memory and serves as a baseline rhythm for a patient. Subsequently, a second signal is sensed from the heart through the SD. A cardiac condition can be detected within the sensed second electrical signal through the SD. A determination is made as to whether cardiac resynchronization therapy (CRT) is appropriate to treat the detected cardiac condition. A determination can then be made as to the timing of pacing pulse delivery to cardiac tissue through a leadless pacing device (LPD). The LPD receives communication from the SD requesting the LPD to deliver CRT to the heart.

Abstract: Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous device (e.g. subcutaneous implantable (SD)) is described. In one or more other embodiments, SD is implanted into a patient's heart. Electrical signals are then sensed which includes moderately lengthened QRS duration data from the patient's heart. A determination is made as to whether cardiac resynchronization pacing therapy (CRT pacing) is appropriate based upon the moderately lengthened QRS duration in the sensed electrical signals. The CRT pacing pulses are delivered to the heart using electrodes. In one or more embodiments, the SD can switch between fusion pacing and biventricular pacing based upon data (e.g. moderately lengthened QRS, etc.) sensed from the heart.