Abstract: Methods and systems involve classifying the cardiac response to pacing using a multi-channel approach. Multiple cardiac response signals are sensed via multiple sense channels. Each sense channel comprises a distinct combination of electrodes and sensing circuitry. The cardiac response to the pacing pulse is classified based on the morphology of the cardiac response signals. Classifying the cardiac response involves discriminating between capture, fusion, non-capture, and non-capture with intrinsic activity.

Abstract: Cardiac devices and methods provide adaptation of detection windows used to determine a cardiac response to pacing. Adapting a detection window involves sensing a cardiac signal indicative of a particular type of cardiac pacing response, and detecting a feature of the sensed cardiac signal. The cardiac response detection window associated with the type of cardiac pacing response is preferentially adjusted based on the location of the detected cardiac feature. Preferential adjustment of the detection window may involve determining a direction of change between the detection window and the detected feature. The detection window may be adapted more aggressively in a more preferred direction and less aggressively in a less preferred direction.

Abstract: A method and system for determining an optimum atrioventricular delay (AVD) interval and/or ventriculo-ventricular delay (VVD) intervals for delivering ventricular resynchronization pacing in an atrial tracking or atrial sequential pacing mode. Evoked response electrograms recorded at different AVD and VVD intervals are used to determine the extent of paced and intrinsic activation.

Abstract: Cardiac devices and methods using cardiac waveform clustering for template generation are described. A method of characterizing a cardiac response involves delivering pacing pulses to heart, the pulses having an energy greater than a capture threshold. Cardiac signals are sensed following the pulses. Cardiac signal characteristics, waveforms, and/or features are clustered into a plurality of clusters. A cardiac response template is formed using one or more of the plurality of clusters.

Abstract: Methods and systems involve classifying the cardiac response to pacing using a multi-channel approach. Multiple cardiac response signals are sensed via multiple sense channels. Each sense channel comprises a distinct combination of electrodes and sensing circuitry. The cardiac response to the pacing pulse is classified based on the morphology of the cardiac response signals. Classifying the cardiac response involves discriminating between capture, fusion, non-capture, and non-capture with intrinsic activity.

Abstract: A remote external interface for an implantable cardiac function management device is configured to be communicatively coupled to the implantable cardiac function management device via a network to a local external interface and via telemetry between the local external interface and the implantable cardiac function management device. The remote external interface includes a communication circuit and a processor circuit. The communication circuit is configured to communicate with the implantable cardiac function management device. The processor circuit is configured to perform an analysis of physiologic data received from the implantable cardiac function management device in response to operation of the implantable cardiac function management device using a plurality of therapy control parameter sets. The processor circuit can be further configured to select a particular therapy control parameter set using the analysis.

Abstract: Approaches for adjusting the pacing energy delivered by a pacemaker are provided. Adjusting the pacing energy involves performing a plurality of capture threshold tests, each capture threshold test measuring a capture threshold of the heart. One or more measured captured thresholds are selected, including at least one capture threshold that is higher relative to other measured capture thresholds acquired by the plurality of capture threshold tests. The pacing energy is adjusted based on the one or more selected capture thresholds.

Abstract: Multi-chamber pacing may result in capture of one chamber, capture of multiple chambers, fusion, or non-capture. Approaches for detecting various capture conditions during multi-chamber pacing are described. Pacing pulses are delivered to left and right heart chambers during a cardiac cycle. A cardiac electrogram signal is sensed following the delivery of the pacing pulses. Left chamber capture only, right chamber capture only, and bi-chamber capture may be distinguished based on characteristics of the cardiac electrogram signal. Multi-chamber capture detection may be implemented using detection windows having dimensions of time and amplitude. The detection windows are associated with expected features, such as expected signal peaks, under a particular capture condition. The cardiac electrogram signal features are compared to detection windows to determine the capture condition.

Abstract: Cardiac devices and methods using cardiac waveform clustering for template generation are described. A method of characterizing a cardiac response involves delivering pacing pulses to heart, the pulses having an energy greater than a capture threshold. Cardiac signals are sensed following the pulses. Cardiac signal characteristics, waveforms, and/or features are clustered into a plurality of clusters. A cardiac response template is formed using one or more of the plurality of clusters.

Abstract: A system evaluates the performance of an implantable medical device, such as by using a remote external server and a user interface and stored historical physiological data of a population of congestive heart failure (CHF) patients. A processor is coupled to a patient data storage device to apply multiple algorithm variations against the same implantable physiological data from the patient to produce corresponding resulting CHF indicators. The user interface includes a display that is configured to display to a user information allowing comparison between the resulting CHF indicators from the multiple algorithm variations. The display also includes a population data selector to permit the user to select physiological data from a population that includes a different set of one or more patients or physiological data collected over a period of time from the patient. This permits optimization of an algorithm parameter or selection of a best performing algorithm.

Abstract: Adjusting the pacing energy involves performing a plurality of capture threshold tests, each capture threshold test measuring a capture threshold of the heart. One or more measured captured thresholds are selected, including at least one capture threshold that is higher relative to other measured capture thresholds acquired by the plurality of capture threshold tests. The pacing energy is adjusted based on the one or more selected capture thresholds.

Abstract: Cardiac devices and methods discriminate non-captured intrinsic beats during evoked response detection and classification by comparing the features of a post-pace cardiac signal with expected features associated with a non-captured response with intrinsic activation. Detection of a non-captured response with intrinsic activation may be based on the peak amplitude and timing of the cardiac signal. The methods may be used to discriminate between a fusion or capture beat and a non-captured intrinsic beat. Discriminating between possible cardiac responses to the pacing pulse may be useful, for example, during automatic capture verification and/or a capture threshold test.

Abstract: A system including at least one implantable sensor circuit adapted to produce an electrical sensor signal related to one or more physiologic cardiovascular events of a subject, a therapy circuit configured to provide anti-tachycardia pacing (ATP) therapy, and a controller. The controller includes a tachyarrhythmia detection circuit and an efficacy circuit. The tachyarrhythmia detection circuit is configured to detect a tachyarrhythmia episode in the subject using the electrical sensor signal, and to determine whether the tachyarrhythmia episode is of a type that is treatable with ATP. The efficacy circuit is configured to estimate an efficacy of a currently configured ATP therapy for the subject, and the controller is configured to alter a delivery regimen of the currently configured ATP therapy when the estimated ATP therapy efficacy is deemed insufficient. Other systems and methods are described.

Abstract: Methods and devices used to classify cardiac events based on morphological analysis of sensed signals are described. A signal comprising a cardiac signal component and a noise signal component is sensed. The sensed signal is processed to preferentially alter morphology of the cardiac signal component. The altered morphology of the cardiac signal component enhances detection of one or more features of the cardiac signal component. The features of the cardiac signal component are detected and the cardiac event is classified using the detected features. Processing the sensed signal may involve the use of adaptable signal processing parameters. For example, the signal processing parameters may be selected to accentuate one or more desirable features of the cardiac signal component or to mitigate one or more undesirable features of the cardiac signal component.

Abstract: Multi-chamber pacing may result in capture of one chamber, capture of multiple chambers, fusion, or non-capture. Approaches for detecting various capture conditions during multi-chamber pacing are described. Pacing pulses are delivered to left and right heart chambers during a cardiac cycle. A cardiac electrogram signal is sensed following the delivery of the pacing pulses. Left chamber capture only, right chamber capture only, and bi-chamber capture may be distinguished based on characteristics of the cardiac electrogram signal. Multi-chamber capture detection may be implemented using detection windows having dimensions of time and amplitude. The detection windows are associated with expected features, such as expected signal peaks, under a particular capture condition. The cardiac electrogram signal features are compared to detection windows to determine the capture condition.

Abstract: Cardiac devices and methods involve the detection of cardiac signals features in adjacent classification intervals. Portions of the cardiac signal features detected in adjacent classification intervals are associated and are used to classify the cardiac response to a pacing pulse. Associating the portions of the cardiac signal features may be based on expected signal morphology.

Abstract: Systems and methods provide for pacing a heart to improve pumping efficiency of the heart, such as by producing a cardiac fusion response for patient's subject to cardiac resynchronization therapy. A pacing parameter, such as an A-V delay, V-V delay, lead/electrode configuration or vector, is adjusted and a cardiac signal vector representative of all or a portion of one or more cardiac activation sequences is monitored during pacing parameter adjustment. A change in a characteristic of the cardiac signal vector is detected in response to an adjusted pacing parameter, the change indicative of a cardiac fusion response. A pacing therapy may be delivered to produce the cardiac fusion response using the adjusted pacing parameter.

Abstract: Approaches for determining energy parameters for electrical stimulation pulses that produce a desired activation and avoid an undesirable activation are described. A strength-duration relationship for at least one desired activation produced by therapeutic electrical stimulation is measured. A strength-duration relationship for at least one undesirable activation produced by the therapeutic electrical stimulation is provided. A medical device selects, based on the desired and undesirable strength-duration relationships, one or more energy parameters for the therapeutic electrical stimulation that produce the desired activation and avoid the undesirable activation.

Abstract: Cardiac devices and methods involve the detection of cardiac signals features in adjacent classification intervals. Portions of the cardiac signal features detected in adjacent classification intervals are associated and are used to classify the cardiac response to a pacing pulse. Associating the portions of the cardiac signal features may be based on expected signal morphology.

Abstract: Adaptive rate pacing for improving heart rate kinetics in heart failure patients involves determining onset and sustaining of patient activity. The patient's heart rate response to the sustained activity is evaluated during a time window defined between onset of the activity and a steady-state exercise level. If the patient's heart rate response to the sustained activity is determined to be slow, a pacing therapy is delivered at a rate greater than the patient's intrinsic heart rate based on a profile of the patient's heart rate response to varying workloads. If determined not to be slow, the pacing therapy is withheld. Monitoring-only configurations provide for acquisition and organization of physiological data for heart failure patients. These data can be acquired on a per-patient basis and used to assess the HF status of the patient.