Abstract: An apparatus comprises a cardiac signal sensing circuit configured to sense a plurality of intrinsic cardiac signals using a plurality of cardiac pacing sites, a heart sound sensing circuit, a stimulus circuit configured to provide an electrical cardiac pacing stimulus to the plurality of pacing sites, and a control circuit electrically coupled to the cardiac signal sensing circuit and the stimulus circuit. The control circuit includes a pacing site locating circuit configured to generate an indication of a preferred pacing site as one of a) a subset of the respective cardiac pacing sites selected using the intrinsic ventricular activation time interval value, from which subset the preferred pacing site is selected using the heart sound characteristic value; or b) a subset of the respective cardiac pacing sites selected using the heart sound characteristic value, from which subset the preferred pacing site is selected using the ventricular activation time interval value.

Abstract: Implanted medical device data is received, where the data was sensed by a first lead portion and a sensor over a time period. The number of detected noise events sensed by the first lead portion is counted based on applying first noise detection criteria to the data sensed by the first lead portion. The number of detected noise events over the sensor is counted based on applying second noise detection criteria to the data sensed by the sensor. The mean number of detected noise events is calculated for the first lead portion and sensor based on the number of noise events sensed by the first lead portion and the number of noise events sensed by the sensor. Potential lead failure in the first lead is recorded if the number of detected noise events over the first lead is greater than the mean number of noise events by at least 5%.

Abstract: An apparatus comprises a primary cardiac signal sensing circuit to sense a first cardiac signal, a secondary cardiac signal sensing to sense a second cardiac signal, and an arrhythmia detection circuit. The primary sensing circuit includes at least first and second implantable electrodes, and the secondary sensing circuit includes a third implantable electrode to deliver high-energy shock therapy. The arrhythmia detection circuit detects tachyarrhythmia using the primary sensing circuit, determines correspondence between events sensed with the primary sensing circuit and events sensed with the secondary sensing circuit, and deems whether a detected rhythm is indicative of noise or is indicative of an arrhythmia according to the determined correspondence.

Abstract: A heart rate variability or heart rate variation can be identified using sensed and/or paced heart beats. One or more patient metrics, such as a variability index or a variation index, can correspond to the identified heart rate variability or heart rate variation. The patient metrics can be used to identify a need for a particular therapy, such as a rate-responsive pacing therapy. The patient metrics can be used to identify patients at an elevated risk of death. Methods and systems to identify therapy indications or at-risk patients are provided. In an example, a patient risk profile can be adjusted, such as in response to an identified patient heart rate variability or heart rate variation. In an example, a rate-responsive pacing mode can be used to adjust the patient risk profile.

Abstract: A method and system for discriminating ventricular arrhythmia is disclosed. In an embodiment, the method can include implementing an arrhythmia discrimination algorithm that can discriminate between supraventricular tachycardia (SVT) and ventricular tachycardia (VT) using at least one programmable parameter programmed to a first value. The method can include analyzing an SVT event, where analyzing the SVT event can include sensing a physiological signal during the SVT event and identifying characteristics of the sensed physiological signal. The method can further include analyzing a cardiac signal to classify the cardiac signal as either an SVT or a VT using the arrhythmia discrimination algorithm with the programmable parameter (programmed to a second value. The second value can be determined from the identified characteristics of the sensed physiological signal.

Abstract: A heart rate variability or heart rate variation can be identified using sensed and/or paced heart beats. One or more patient metrics, such as a variability index or a variation index, can correspond to the identified heart rate variability or heart rate variation. The patient metrics can be used to identify a need for a particular therapy, such as a rate-responsive pacing therapy. The patient metrics can be used to identify patients at an elevated risk of death. Methods and systems to identify therapy indications or at-risk patients are provided. In an example, a patient risk profile can be adjusted, such as in response to an identified patient heart rate variability or heart rate variation. In an example, a rate-responsive pacing mode can be used to adjust the patient risk profile.

Abstract: An atrial event and a ventricular event can be received, and an atrioventricular (AV) delay can be provided using information about the atrial and ventricular events. The AV delay can be increased after a first condition is satisfied to allow a heart to regain intrinsic control of ventricular activation, and changed after a second condition is satisfied to allow the heart to remain in intrinsic control of ventricular activation.

Abstract: In an example, a medical device includes a physiological data monitor (PDM), a memory, and a processor. The PDM is configured to monitor a physiological data parameter. The memory circuit is configured to store data collected by the PDM. The processor is configured to detect a data capture event and capture a first segment of physiological data associated with the data capture event. The processor is also configured to determine an amount of memory storage space available and determine a first priority level for the first segment of physiological data. The processor is further configured to determine a second priority level for a second segment of physiological data stored previously and select a processing scheme using the first and second priority levels. Finally, the processor is configured to process, using the processing scheme, the first and second segments of physiological data and store the first segment of physiological data.

Abstract: An apparatus comprises an implantable cardiac signal sensing circuit and a controller circuit. The implantable cardiac signal sensing circuit provides a sensed depolarization signal from a ventricle and a sensed depolarization signal from an atrium. The controller circuit includes a one-to-one detector circuit and a tachyarrhythmia discrimination circuit. The one-to-one detector circuit measures cardiac depolarization intervals of the atrium and the ventricle and determines whether a relationship of atrial depolarizations to ventricular depolarizations is substantially one-to-one. The tachyarrhythmia discrimination circuit classifies the episode as VT when detecting a shortening or prolonging of a V-V interval that immediately precedes the same shortening or prolonging of an A-A interval.

Abstract: The current technology is relevant to a system having an implantable medical device, where the system is configured to identify a patient condition comprising cardiac dysynchrony, configured to notify a clinical user of the identified condition and configured to identify a therapy appropriate for the identified condition.

Abstract: The technology disclosed herein relates to a method for lead analysis for an implanted medical device. A summary data record is retrieved associated with one or more episodes from an implanted medical device through a communication module. Episode selection criteria are applied to the summary data record by a processing module. One or more episode data records are retrieved from the implanted medical device for one or more episodes for which the episode selection criteria was satisfied. Noise detection criteria are applied to the episode data record.

Abstract: Monitoring physiological parameter using an implantable physiological monitor in order to detect a condition predictive of a possible future pathological episode and collecting additional physiological data associated with the condition predictive of a possible future pathological episode. Monitoring another physiological parameter in order to detect a condition indicative of the beginning of a present pathological episode and collecting additional pathological data in response to the condition. Determining that the condition predictive of a future episode and the condition indicative of a present episode are associated and, in response thereto, storing all the collected physiological data.

Abstract: An apparatus comprises a primary cardiac signal sensing circuit configured to sense at least a first cardiac signal, a secondary cardiac signal sensing circuit configured to sense a secondary cardiac signal, and a control circuit. The control circuit includes a noise detection circuit that has an alignment circuit. The alignment circuit is configured to align a segment of the sensed first cardiac signal with a segment of the sensed secondary cardiac signal. The noise detection circuit configured to determine a number of turns in the first cardiac signal segment, determine a number of turns in the secondary cardiac signal segment, generate an indication of noise in the first and secondary cardiac signals according to the determined number of turns, and provide the indication of noise to a user or process.

Abstract: A method and system for discriminating ventricular arrhythmia is disclosed. In an embodiment, the method can include implementing an arrhythmia discrimination algorithm that can discriminate between supraventricular tachycardia (SVT) and ventricular tachycardia (VT) using at least one programmable parameter programmed to a first value. The method can include analyzing an SVT event, where analyzing the SVT event can include sensing a physiological signal during the SVT event and identifying characteristics of the sensed physiological signal. The method can further include analyzing a cardiac signal to classify the cardiac signal as either an SVT or a VT using the arrhythmia discrimination algorithm with the programmable parameter (programmed to a second value. The second value can be determined from the identified characteristics of the sensed physiological signal.

Abstract: Monitoring physiological parameter using an implantable physiological monitor in order to detect a condition predictive of a possible future pathological episode and collecting additional physiological data associated with the condition predictive of a possible future pathological episode. Monitoring another physiological parameter in order to detect a condition indicative of the beginning of a present pathological episode and collecting additional pathological data in response to the condition. Determining that the condition predictive of a future episode and the condition indicative of a present episode are associated and, in response thereto, storing all the collected physiological data.

Abstract: An implantable or ambulatory medical device can include a cardiac signal sensing circuit configured to provide a sensed cardiac depolarization signal of a heart of a subject, a respiration sensing circuit configured to provide a signal representative of respiration of the subject, and a control circuit communicatively coupled to the cardiac signal sensing circuit and the respiration circuit. The control circuit includes a tachyarrhythmia detection circuit configured to determine heart rate using the depolarization signal, determine a respiration parameter of the subject using the respiration signal, calculate a ratio using the determined heart rate and the determined respiration parameter, generate an indication of tachyarrhythmia when the calculated ratio satisfies a specified detection ratio threshold value, and provide the indication of tachyarrhythmia to a user or process.

Abstract: A system and method for passively testing a cardiac pacemaker in which sensing signal amplitudes and lead impedance values are measured and stored while the pacemaker is functioning in its programmed mode. The amplitude and impedance data may be gotten and stored periodically at regular intervals to generate a historical record for diagnostic purposes. Sensing signal amplitudes may also be measured and stored from a sensing channel which is currently not programmed to be active as long as the pacemaker is physically configured to support the sensing channel. Such data can be useful in evaluating whether a switch in the pacemaker's operating mode is desirable.

Abstract: The current technology is relevant to a system having a programming device capable of communication with an implantable medical device, where the a programming device is configured to identify a patient condition comprising the patient's inability to exercise to a desired capacity, configured to notify a clinical user of the identified condition and configured to identify a therapy appropriate for the identified condition.

Abstract: A method and system for generating a characterization of one beat of a patient's supraventricular rhythm (SVR) involves performing such characterization while the heart is being paced. During SVR characterization, various pacing parameters are modified and the patient's supraventricular rhythm is characterized while the pacing parameters are modified. The SVR characterization process is effective in single and multiple chamber pacing modes.

Abstract: An arrhythmia classification system receives cardiac data from an implantable medical device, performs automatic adjudication of each cardiac arrhythmia episode indicated by the cardiac data, and generates episode data representative of information associated with the episode. The episode data include at least an episode classification resulting from the automatic adjudication of the episode and a confidence level in the episode classification. In one embodiment, the episode data further include key features rationalizing the automatic adjudication of the episode.