Abstract: Methods of cardiac rhythm analysis in an implantable cardiac stimulus device, and devices configured for such methods. In an illustrative embodiment, certain data relating to cardiac event rate or amplitude is modified following delivery of a cardiac stimulus. In another embodiment, cardiac rhythm analysis is performed using one of plural states, with the plural states using different criteria, such as a detection threshold, to detect cardiac events in a sensed signal. Following delivery of a cardiac stimulus, data is manipulated to force the analysis into one of the states, where stimulus is delivered, in the illustrative embodiment, only after a different state is invoked. Implantable devices incorporating operational circuitry for performing such methods are also included in other illustrative embodiments.

Abstract: In a subcutaneous implantable cardioverter/defibrillator, cardiac arrhythmias are detected to determine necessary therapeutic action. Cardiac signal information is sensed from far field electrodes implanted in a patient. The sensed cardiac signal information is then amplified and filtered. Parameters such as rate, QRS pulse width, cardiac QRS slew rate, amplitude and stability measures of these parameters from the filtered cardiac signal information are measured, processed and integrated to determine if the cardioverter/defibrillator needs to initiate therapeutic action.

Abstract: Methods and implantable devices for cardiac signal analysis. The methods and devices make use of waveform appraisal techniques to distinguish event detections into categories for suspect events and waveform appraisal passing events. When adjustments are made to the data entering analysis for waveform appraisal, the waveform appraisal thresholds applied are modified as well. For example, when the data analysis window for waveform appraisal changes in length, a waveform appraisal threshold is modified. Other changes, including changes in sensing characteristics with which waveform appraisal operates may also result in changes to the waveform appraisal threshold including changes in gain, sensing vector, activation of other devices, implantee posture and other examples which are explained.

Abstract: Methods and implantable devices that address response to, or avoidance of, likely non-cardiac voltages including after potentials from external or internal stimulus. Also, methods of operation in implantable medical devices, the methods configured for identifying saturation of input circuitry and mitigating the effects of such saturation. Also, implantable cardiac stimulus or monitoring devices that include methods for identifying saturated conditions and mitigating the effects of such saturation.

Abstract: Methods of cardiac rhythm analysis in an implantable cardiac stimulus device, and devices configured for such methods. In an illustrative embodiment, certain data relating to cardiac event rate or amplitude is modified following delivery of a cardiac stimulus. In another embodiment, cardiac rhythm analysis is performed using one of plural states, with the plural states using different criteria, such as a detection threshold, to detect cardiac events in a sensed signal. Following delivery of a cardiac stimulus, data is manipulated to force the analysis into one of the states, where stimulus is delivered, in the illustrative embodiment, only after a different state is invoked. Implantable devices incorporating operational circuitry for performing such methods are also included in other illustrative embodiments.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In illustrative examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. In some illustrative examples, when overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data. New methods for organizing the use of morphology and rate analysis in an overall architecture for rhythm classification and cardiac signal analysis are also discussed.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In some examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. In some illustrative examples, when overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data. Several examples emphasize the use of morphology analysis using correlation to static templates and/or inter-event correlation analysis.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In some illustrative examples, detected events are analyzed to identify changes in detected event amplitudes. When detected event amplitudes are dissimilar from one another, a first set of detection parameters may be invoked, and, when detected event amplitudes are similar to one another, a second set of detection parameters may be invoked. Additional methods determine whether the calculated heart rate is “high” or “low,” and then may select a third set of detection parameters for use when the calculated heart rate is high.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In illustrative examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. In some illustrative examples, when overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data. New methods for organizing the use of morphology and rate analysis in an overall architecture for rhythm classification and cardiac signal analysis are also discussed.

Abstract: Devices and methods for analyzing cardiac signal data. An illustrative method includes identifying a plurality of detected events and measuring intervals between the detected events for use in rate estimation. In the illustrative embodiment, a set of intervals is used to make the rate estimation by first discarding selected intervals from the set. The remaining intervals are then used to calculate an estimated interval, for example by averaging the remaining intervals.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In illustrative examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. In some illustrative examples, when overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data. New methods for organizing the use of morphology and rate analysis in an overall architecture for rhythm classification and cardiac signal analysis are also discussed.

Abstract: Implantable cardiac devices and methods of their use. A method of operation in an implantable cardiac device may include steps for characterizing detected events as noise or not noise, identifying a set of consecutive noise events or a threshold quantity of noise events in a set period of time and declaring a noisy series to have occurred. In response to the declaration of a noisy series, the method initiates a baseline correction algorithm. Devices for performing such methods are also disclosed.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In some examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. In some illustrative examples, when overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data. Several examples emphasize the use of morphology analysis using correlation to static templates and/or inter-event correlation analysis.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In illustrative examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. In some illustrative examples, when overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data. New methods for organizing the use of morphology and rate analysis in an overall architecture for rhythm classification and cardiac signal analysis are also discussed.

Abstract: Devices and methods for analyzing cardiac signal data. An illustrative method includes identifying a plurality of detected events and measuring intervals between the detected events for use in rate estimation. In the illustrative embodiment, a set of intervals is used to make the rate estimation by first discarding selected intervals from the set. The remaining intervals are then used to calculate an estimated interval, for example by averaging the remaining intervals.

Abstract: Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In some illustrative examples, detected events are analyzed to identify changes in detected event amplitudes. When detected event amplitudes are dissimilar from one another, a first set of detection parameters may be invoked, and, when detected event amplitudes are similar to one another, a second set of detection parameters may be invoked. Additional methods determine whether the calculated heart rate is “high” or “low,” and then may select a third set of detection parameters for use when the calculated heart rate is high.

Abstract: Methods, implantable medical devices and systems configured to perform analysis of captured signals from implanted electrodes to identify cardiac arrhythmias. In an illustrative embodiment, signals captured from two or more sensing vectors are analyzed, where the signals are captured with a patient in at least first and second body positions. Analysis is performed to identify primary or default sensing vectors and/or templates for event detection.

Abstract: Methods of cardiac rhythm analysis in an implantable cardiac stimulus device, and devices configured for such methods. In an illustrative embodiment, certain data relating to cardiac event rate or amplitude is modified following delivery of a cardiac stimulus. In another embodiment, cardiac rhythm analysis is performed using one of plural states, with the plural states using different criteria, such as a detection threshold, to detect cardiac events in a sensed signal. Following delivery of a cardiac stimulus, data is manipulated to force the analysis into one of the states, where stimulus is delivered, in the illustrative embodiment, only after a different state is invoked. Implantable devices incorporating operational circuitry for performing such methods are also included in other illustrative embodiments.

Abstract: In a subcutaneous implantable cardioverter/defibrillator, cardiac arrhythmias are detected to determine necessary therapeutic action. Cardiac signal information is sensed from far field electrodes implanted in a patient. The sensed cardiac signal information is then amplified and filtered. Parameters such as rate, QRS pulse width, cardiac QRS slew rate, amplitude and stability measures of these parameters from the filtered cardiac signal information are measured, processed and integrated to determine if the cardioverter/defibrillator needs to initiate therapeutic action.

Abstract: Methods of cardiac rhythm analysis in an implantable cardiac stimulus device, and devices configured for such methods. In an illustrative embodiment, certain data relating to cardiac event rate or amplitude is modified following delivery of a cardiac stimulus. In another embodiment, cardiac rhythm analysis is performed using one of plural states, with the plural states using different criteria, such as a detection threshold, to detect cardiac events in a sensed signal. Following delivery of a cardiac stimulus, data is manipulated to force the analysis into one of the states, where stimulus is delivered, in the illustrative embodiment, only after a different state is invoked. Implantable devices incorporating operational circuitry for performing such methods are also included in other illustrative embodiments.