Abstract: Systems, methods, devices, and other techniques for processing an ECG recording to assess a condition of a mammal. Assessing the condition of the mammal can include screening for atrial fibrillation, and screening for atrial fibrillation can include obtaining a first neural network input, the first neural network input representing an electrocardiogram (ECG) recording of the mammal, and processing the first neural network input with a neural network to generate an atrial fibrillation prediction for the mammal.

Abstract: An apparatus for assessing a coronary vasculature and a corresponding method are provided which allow to globally assess a coronary artery disease directly from the contrast agent dynamics as derived from diagnostic images acquired using an invasive medical imaging modality by following the time course of the area occupied by the vessels in the diagnostic images.

Abstract: In embodiments a wearable cardioverter defibrillator (WCD) system is worn by an ambulatory patient. The WCD system analyzes an ECG signal of the patient, to determine whether or not the patient should be given an electric shock to restart their heart. If the WCD system determines that such a shock should be given, then it also determines whether or not a High Frequency (H-F) noise criterion is met by the ECG signal. If that H-F noise criterion is not met, the patient can be shocked. If, however, that H-F noise criterion is met, then the WCD system can confirm before shocking, by sensing another portion of the ECG signal, analyzing again, and so on. Thanks to the confirmation before shocking, the possibility is diminished that the ECG signal will indicate that a shock is needed falsely, due to H-F noise. This can further reduce false patient alarms, and so on.

Abstract: The present disclosure relates to a method for analyzing an R-wave of an electrocardiogram (ECG) signal. The method includes obtaining an original ECG signal of a subject; filtering the original ECG signal; determining whether to trigger a search gate based on the filtered ECG signal, wherein the search gate is an instruction for detecting an R-wave on the original ECG signal; and detecting the R-wave on the original ECG signal in response to a determination of triggering the search gate.

Abstract: One or more embodiments relate to a bio-signal measurement apparatus and a bio-signal measurement method for detecting peaks and a computer program for executing the method. Sensed ECG signal is wavelet transformed into one or more levels, and an effective peak of a bio-signal is detected using a complexity value of a signal surrounding the peak in the converted signals.

Abstract: Disclosed systems include an electrocardiogram sensor and a processing device operatively coupled to the electrocardiogram sensor. The processing device receives electrocardiogram data from the electrocardiogram sensor and applies a machine learning model to the received electrocardiogram data. The machine learning model has been trained based on previous electrocardiogram data of a plurality of subjects. The electrocardiogram data of the plurality of subjects have one or more associated analyte measurements. The processing device may determine an indication of a level of the analyte based on the electrocardiogram data.

Abstract: An apparatus comprising: circuitry configured to classify a signal; and circuitry configured to control saving of the signal to a memory with a conditional resolution, wherein a signal that is classified as anomalous is saved at higher resolution as a higher resolution signal and a signal that is not classified as anomalous is saved at lower resolution as a lower resolution signal or is not saved.

Abstract: The invention comprises a system that monitors heart activity through embedded ECG sensors in a desk, and desk-related amenities such as a chair, a computer keyboard, a mouse, and a floor mat. The invention also comprises pressure sensors for monitoring a user's presence at the desk. Signals measured from the ECG or pressure sensors are transmitted (in a wired, or wireless fashion) to a computer processing device which applies algorithms to refine the collected signals, and passively estimate the user's ECG.

Abstract: In embodiments, a wearable cardioverter defibrillator (WCD) system includes electrodes that render an ECG signal of the patient, and a processor that receives ECG data are derived from the rendered ECG signal. The processor may filter the received ECG data with a matched difference filter to detect QRS complexes, and compute a heart rate from the detected QRS complexes. The matched difference filter itself can have coefficient values associated with a baseline QRS complex, which improves detection.

Abstract: A medical device is configured to determine time intervals between consecutive cardiac events sensed from a cardiac electrical signal, increase a value of a tachyarrhythmia interval count in response to each of the determine time intervals detected as a tachyarrhythmia interval. The device is further configured to detect normal sinus rhythm events and the decrease the value of the tachyarrhythmia interval count in response to a threshold number of detected normal sinus rhythm events.

Abstract: A method and system for determining QRS onset in cardiac signals is described. The system and method comprise acquiring N ECG signals and each comprises a plurality of QRS complexes. The system and method further selecting one QRS complex to form the basis of a search for the QRS onset point and defining a starting location within the ECG signal that has the selected QRS complex for the search. Further, the method and system comprises searching backwards in time from said starting location for a first nadir in the signal associated with the selected QRS complex and setting the time of the first nadir as the time for the QRS onset point.

Abstract: A medical device is configured to sense event signals from a cardiac electrical signal and determine maximum amplitudes of cardiac electrical signal segments associated with sensed event signals. The medical device is configured to determine at least one tachyarrhythmia metric based on at least a greatest one of the determined maximum amplitudes. The medical device may determine when the at least one tachyarrhythmia metric does not meet true tachyarrhythmia evidence and, in response, determine when the maximum amplitudes meet suspected noise criteria. The medical device may withhold a tachyarrhythmia detection and tachyarrhythmia therapy when suspected noise criteria are met.

Abstract: An aspect of the disclosure sets forth a turn signal system for a steering wheel that is easier to use and improves turn signal usage compliance and, accordingly, safety. The turn signal system includes at least one hand location detection sensor; at least one pressure actuated switch mechanism which is actuatable by the operator; a turn signal control, the turn signal control operatively connected to the at least one hand location detection sensor and the at least one pressure actuated switch mechanism, the turn signal control also operatively connected to left and right turn signals of the vehicle to indicate a turn to the left or right. Wherein actuation of the at least one pressure actuated switch mechanism by a hand of the operator of the vehicle provides a signal to the turn signal control to indicate a turn to the left or right.

Abstract: Systems and methods are provided for analyzing electrocardiogram (ECG) data of a patient using a substantial amount of ECG data. The systems receive ECG data from a sensing device positioned on a patient such as one or more ECG leads. The system may include an application that communicates with an ECG platform running on a server(s) that processes and analyzes the ECG data, e.g., using neural networks for delineation of the cardiac signal and classification of various abnormalities, conditions and/or descriptors. The processed ECG data is communicated from the server(s) for display in a user-friendly and interactive manner with enhanced accuracy.

Abstract: A method comprising: receiving a plurality of data segments each representing human cardiac activity; calculating, from each of said data segments, a first value representing a distribution of a heart rate variability (HRV) parameter; acquiring a signal representing cardiac activity in a patient; deriving a second value representing distribution of an HRV parameter in said signal; and indicating an atrial fibrillation (AF) event in said patient, when a difference between said first and second values is above a predetermined threshold.

Abstract: A method for analyzing arrhythmia in real time and an electrocardiogram monitoring device is disclosed. The method for analyzing arrhythmia in real time includes: acquiring a QRS template set currently used for arrhythmia analysis; determining whether each QRS template in the QRS template set is reliable; displaying information of a QRS template when the QRS template set contains an unreliable QRS template; determining the QRS template set according to an operation performed by a user on the information of the QRS template; and acquiring real-time electrocardiogram data, performing arrhythmia analysis on the real-time electrocardiogram data by using a determined QRS template set, and outputting an arrhythmia analysis result of the real-time electrocardiogram data in real time. The method for analyzing arrhythmia in real time may achieve the correction of a template of a special waveform by means of editing a currently created QRS template.

Abstract: This disclosure is directed towards detecting artifacts in an ECG signal. An ECG system may include multiple sensors which can sense an ECG signal when attached to a patient. Bipolar leads connect the sensors, and provide the ECG signal from the sensors to a computing device. The computing device receives respective signals from the bipolar leads, where the respective signals are indicative of the ECG signal. The computing device identifies, based on the respective signals, a potential artifact corresponding to a subset of the plurality of bipolar leads. The computing device determines that each lead of the subset of the plurality of bipolar leads is connected to a common sensor. The computing device may use signals originating from a remainder of the bipolar leads (e.g., the bipolar leads that are not connected to the sensor(s) where the artifact is detected) to detect a condition of the patient.

Abstract: The present disclosure relates to a detection circuit for detecting oscillations of a regulated supply signal. The detection circuit includes a filter circuit to filter the regulated supply signal in order to obtain a filtered supply signal. A peak value detector circuit is designed to detect an extremum of the filtered supply signal. A comparator circuit is designed to compare the detected extreme value with a threshold value and to indicate an understepping or exceedance of the threshold value.

Abstract: Computer implemented methods and systems are provided that comprise, under control of one or more processors of a medical device, where the one or more processors are configured with specific executable instructions. The methods and systems obtain motion data indicative of at least one of a posture or a respiration cycle; obtain cardiac activity (CA) signals for a series of beats; identify whether a characteristic of interest (COI) from at least a first segment of the CA signals exceeds a COI limit; analyze the motion data to determine whether at least one of the posture or respiration cycle at least in part caused the COI to exceed the COI limit. Based on the analyzing operation, the methods and systems automatically adjust a CA sensing parameter utilized by the medical device to detect R-waves in subsequent CA signals; and detect an arrhythmia based on a presence or absence of one or more of the R-waves in at least a second segment of the CA signals.

Abstract: A method of generating ECG reference data for MR image data acquisition includes obtaining an initial ECG dataset from a patient prior to moving the patient into a bore of the MRI device, wherein the initial ECG dataset comprises at least two channels of ECG data. An initial set of R-peaks is identified and an initial R-peak polarity and initial R-R interval are determined. A reference ECG dataset is then obtained from the patient once the patient is in the bore of the MRI device. A reference set of R-peaks is identified in the reference ECG dataset based on the initial R-peak polarity and the initial R-R interval, and R-peak reference data is generated based on the reference set of R-peaks. Acquisition of MR image data from the subject is then triggered using the R-peak reference data.

Abstract: A computer implemented method and system for confirming a device documented arrhythmia in cardiac activity are provided. The method is under control of one or more processors configured with executable instructions. The method obtains a cardiac activity (CA) data set that includes CA signals for a series of cardiac events and includes device documented (DD) markers within the series of cardiac events. The device documented markers are indicative of atrial fibrillation (AF) detected by the ICM utilizing an on-board R-R interval irregularity (ORI) process to analyze the CA signals. The method applies a feature enhancement function to the CA signals to form modified CA signals with enhanced sinus features and analyzes the enhanced sinus features in the modified CA signals. The method utilized a confirmatory feature detection process to identify false AF detection by the ORI process. The method records a result of the analysis identifying false AF detection by the ORI process.

Abstract: Apparatus, including a set of N electrodes (22), configured to be located in proximity to an epidermis (24) of a subject, and to acquire signals generated by electric sources within the subject. The apparatus also includes a set of M channels, configured to transfer the signals, where M is less than N, and a switch (40), configured to select, repetitively and randomly, M signals from the N electrodes and to direct the M signals to the M channels. The apparatus further includes a processor (28), configured to activate the switch, and to receive and analyze the M signals from the M channels so as to determine respective positions of the electric sources within the subject.

Abstract: A method of determining signal quality in a patient monitoring device includes acquiring one or more signals using the patient monitoring device. One or more signal quality metrics are determined based on the one or more acquired signals. A noise condition is detected based on the one or more signal quality metrics, and a determination is made whether the noise condition should be classified as intermittent or persistent. One or more actions are taken based on the classification of detected noise as intermittent or persistent.

Abstract: A system and method for detecting and verifying bradycardia/asystole episodes includes sensing an electrogram (EGM) signal. The EGM signal is compared to a primary threshold to sense events in the EGM signal, and at least one of a bradycardia or an asystole is detected based on the comparison. In response to detecting at least one of a bradycardia or an asystole, the EGM signal is compared to a secondary threshold to sense events under-sensed by the primary threshold. The validity of the bradycardia or the asystole is determined based on the detected under-sensed events.

Abstract: A method for assessing electrocardiogram signal quality, the method comprising: receiving heart beat analysis data by processing electrocardiogram data acquired from an electrocardiogram monitoring device; extracting position information and width information of a QRS complex in the heart beat analysis data; extracting an RR interval signal between two adjacent QRS complex signals; performing QRS complex signal cancellation processing on the RR interval signal to obtain an RR interval signal for which the QRS complex signal is removed; filtering the processed RR interval signal without the QRS complex signal, and performing envelope calculation on the filtered signal to obtain the average power of a noise signal of the RR interval signal for which the QRS complex signal is removed; obtaining a signal quality evaluation index according to the average power of the noise signal and the power of the QRS complex signal.

Abstract: There is disclosed herein examples of systems and methods for compressing a signal. Samples of the signal can be segmented and the samples within each of the segments can be averaged to produce a value that can represent the samples within the segment. The number of samples to average in each segment may be determined based on an error threshold, such that the number of samples being averaged can be maximized to produce less data to be transmitted while maintaining the representation of the samples within the error threshold. In some embodiments, a signal can be separated into a timing reference, a representative periodic function, and a highly compressible error signal. The error signal can be utilized for reproducing a representation of the signal.

Abstract: A QRS complex detection method is provided. The method includes collecting an ECG signal and filtering the ECG signal by using at least one preset filter. The filtered ECG signal is processed using a dual-slope method. Once R wave peak is detected from the processed ECG signal, a position of a QRS complex is outputted based on the R wave peak.

Abstract: A method and medical device for adjusting a blanking period that includes sensing cardiac signals from a plurality of electrodes, the plurality of electrodes forming a plurality of sensing vectors, determining whether to adjust a blanking period during a first operating state, advancing from the first operating state to a second operating state in response to the sensed cardiac signals, determining, while in the second operating state, whether the blanking period was adjusted while in the first operating state, and adjusting the blanking period while in the second operating state in response to the blanking period being adjusted while in the first operating state.

Abstract: In embodiments a wearable cardioverter defibrillator (WCD) system is worn by an ambulatory patient. The WCD system analyzes an ECG signal of the patient, to determine whether or not the patient should be given an electric shock to restart their heart. If the WCD system determines that such a shock should be given, then it also determines whether or not a High Frequency (H-F) noise criterion is met by the ECG signal. If that H-F noise criterion is not met, the patient can be shocked. If, however, that H-F noise criterion is met, then the WCD system can confirm before shocking, by sensing another portion of the ECG signal, analyzing again, and so on. Thanks to the confirmation before shocking, the possibility is diminished that the ECG signal will indicate that a shock is needed falsely, due to H-F noise. This can further reduce false patient alarms, and so on.

Abstract: Discussed are a photovoltaic module and a photovoltaic system including the same. According to an embodiment, the photovoltaic module includes a solar cell module including a plurality of solar cells, and a junction box attached to a back surface of the solar cell module, wherein the junction box includes a capacitor unit to store a direct current (DC) power from the solar cell module, and a shutdown unit disposed at a front end of the capacitor unit and to operate to consume the DC power stored in the capacitor unit and temporarily interrupt power output of the solar cell module when the DC power from the solar cell module is outside of a permissible range. Thus, when DC power outside of the permissible range is supplied, the power output can be quickly interrupted while the DC power stored in the capacitor is consumed.

Abstract: Systems and methods for pacing cardiac conductive tissue are described. A medical system includes an electrostimulation circuit to generate His-bundle pacing (HBP) pulses for delivery at or near a His bundle of the heart. A control circuit may time the delivery of the HBP pulses within a tissue refractory period subsequent to an intrinsic His-bundle activation of a first His-bundle portion. Based on an evoked His-bundle activation of a second His-bundle portion, the system may determine whether correction of intra-Hisian block has occurred. The system additionally includes a threshold test circuit to determine an individualized pacing threshold representing minimal energy to excite the His bundle and to correct the cardiac conduction abnormality.

Abstract: In embodiments a WCD system is worn and/or carried by an ambulatory patient. The WCD system analyzes an ECG signal of the patient, to determine whether or not the patient should be given an electric shock to restart their heart. If so, then the WCD system first gives a preliminary alarm to the patient, asking them to prove they are alive if they are. The WCD system further determines whether the ECG signal contains too much High Amplitude (H-A) noise, which can distort the analysis of the ECG signal. If too much H-A noise is detected for a long time, the WCD system may eventually alert the patient about their activity, so that the ECG noise may be abated. The WCD system may even pause the analysis of the ECG signal, so that there will be no preliminary alarms that could be false until the ECG noise is abated.

Abstract: A system and method for ECG data classification for use in facilitating diagnosis of cardiac rhythm disorders is provided. ECG data is obtained via an electrocardiography monitor shaped for placement on a patient's chest. The ECG data is divided into segments and noise detection analysis is applied to the ECG data segments. A noise classification or a valid classification is assigned to each segment of the ECG data. At least one ECG data segment assigned the noise classification and that includes ECG data that corresponds with feedback from the patient via the electrocardiography monitor is identified. The ECG data that corresponds with the patient feedback is removed from the identified ECG data segment with the noise classification. The ECG data segments assigned the noise classification are removed from further analysis.

Abstract: According to an example aspect of the present invention, there is provided a system for heart rate monitoring of an object, the system comprising means for measuring heart beats of the object with a first unit at a first sampling rate, determining a heart rate, determining a time difference between consecutive heart beats, determining a time of each heart beat, or determining at least a part of a wave form of a heart beat signal, wherein the first unit includes further means for changing the sampling rate as a response to the determined information.

Abstract: A system including a medical device is provided. The medical device includes at least one sensor configured to acquire first data descriptive of a patient, first memory storing a plurality of templates, and at least one processor coupled to the at least one sensor and the first memory. The at least one processor is configured to identify a first template of the plurality of templates that is similar to the first data, to determine first difference data based on the first template and the first data, and to store the first difference data in association with the first template. The system may further include the programmable device.

Abstract: Methods and devices for sensing vector analysis in an implantable cardiac stimulus system. In an illustrative example, a first sensing vector is analyzed to determine whether it is suitable, within given threshold conditions, for use in cardiac event detection and analysis. If so, the first vector may be selected for detection and analysis. Otherwise, one or more additional vectors are analyzed. A detailed example illustrates methods for analyzing sensing vectors by the use of a scoring system. Devices adapted to perform these methods are also discussed, including implantable medical devices adapted to perform these methods, and systems comprising implantable medical devices and programmers adapted to communicate with implantable medical devices, the systems also being adapted to perform these methods. Another example includes a programmer configured to perform these methods including certain steps of directing operation of an associated implanted or implantable medical device.

Abstract: An apparatus includes: a storage configured to store a data structure including first one or more feature points hierarchically listed and a contribution list including information about a contribution rank of each of second one or more feature points; and a controller configured to compare the first one or more feature points in the data structure with the second one or more feature points of the contribution list, and to determine whether to update the data structure based on a comparison result.

Abstract: Methods, noise detection devices, and differential voltage measuring systems are provided for detecting noise signals for the purpose of measuring cardiac movements in a patient. In the method, contact is made with the patient by at least two measuring electrodes having at least one associated measuring channel. Furthermore, a heartbeat measurement is performed. During the heartbeat measurement, signals from the patient are detected over the at least one measuring channel. Then, a check is made of whether the detected signals have been caused by noise by comparing the detected signals with at least one heartbeat type that was identified in the course of the learning procedure.

Abstract: A system and method for detecting and verifying bradycardia/asystole episodes includes sensing an electrogram (EGM) signal. The EGM signal is compared to a primary threshold to sense events in the EGM signal, and at least one of a bradycardia or an asystole is detected based on the comparison. In response to detecting at least one of a bradycardia or an asystole, the EGM signal is compared to a secondary threshold to sense events under-sensed by the primary threshold. The validity of the bradycardia or the asystole is determined based on the detected under-sensed events.

Abstract: A cardiac potential detection device for detecting R-waves from an electrocardiographic waveform includes a plurality of electrodes, a detector, and a control unit. The detector detects an input voltage applied from the electrodes. The control unit identifies an R-wave based on the input voltage detected by the detector, but suspends identifying R-waves in a detection-suspension period including a period in which the input voltage exceeds a predetermined threshold.

Abstract: Methods and apparatus perform periodic breathing detection, such as Cheyne-Stokes respiration detection. The detection may be performed by one or more processors, such as by analysis of data from one or more sensors. In some cases, the detection may be based on an electrocardiogram (ECG) signal, such as from ECG electrodes and/or an accelerometer signal, such as from an accelerometer. An occurrence of periodic breathing may be detected based on features derived from the signal(s). For example, detection may be based on deriving a respiration signal from the sensed signal(s) and/or analysis of RR interval times or relative QRS amplitude values, which may be evaluated on a segment-by-segment basis. The detection may provide monitoring and reporting of the occurrence of periodic breathing by a monitoring device and/or provide a basis for controlling changes to a provided respiratory treatment or therapy, such as by a respiratory pressure therapy device.

Abstract: A method and system for filtering a detected ECG signal are disclosed. In a first aspect, the method comprises filtering the detected ECG signal using a plurality of digital filters. The method includes adaptively selecting one of the plurality of digital filters to maintain a minimum signal-to-noise ratio (SNR). In a second aspect, the system comprises a wireless sensor device coupled to a user via at least one electrode, wherein the wireless sensor device includes a processor and a memory device coupled to the processor, wherein the memory device stores an application which, when executed by the processor, causes the processor to carry out the steps of the method.

Abstract: Systems and methods are provided to detect subwaveforms of an ECG waveform. Electrical impulses are detected between at least one pair of electrodes of two or more electrodes placed proximate to a beating heart and are converted to an ECG waveform for each heartbeat of the beating heart using the detector. One or more subwaveforms within P, Q, R, S, T, U, and J waveforms of the ECG waveform for each heartbeat or in an interval between the P, Q, R, S, T, U, and J waveforms that represent the depolarization or repolarization of an anatomically distinct portion of muscle tissue of the beating heart are detected using a signal processor. A processed ECG waveform that includes the one or more subwaveforms for each heartbeat is produced using the signal processor. The processed ECG waveform is received from the signal processor is displayed using a display device.

Abstract: A subcutaneously implantable cardiac medical device and a method of sensing a cardiac signal therein that includes a plurality of electrodes to sense a cardiac signal along a plurality of sensing vectors to detect a first interval and a second interval associated with a first detected event, and a processor configured to determine whether the first interval and the second interval are shorter than a predetermined threshold, determine whether the first interval and the second interval are similar, and determine, in response to the first interval and the second interval being similar, whether the sensed cardiac signal is either a noisy signal or a QRS signal.

Abstract: The present invention proposes a relaxation state evaluation system and method and a computer program product thereof. The method comprises steps: measuring ECG data of a user; analyzing the ECG data to generate a first, second, third and fourth parameters, wherein the first parameter is the short-scale entropy slope of the user before cardiovascular disease treatment (CVDT); the second parameter is the difference of the post-CVDT and pre-CVDT mean RR intervals; the third parameter is the logarithm of the variance of the pre-CVDT high frequency NN intervals; the fourth parameter is the logarithm of the ratio of the variances of the pre-CVDT low frequency and high frequency NN intervals; working out an evaluation index, which is a function of the abovementioned parameters; and evaluating the relaxation state of the user, wherein the user is determined to be in a relaxation state if the evaluation index is over a threshold.

Abstract: A method of providing a graphical representation of sleep quality includes obtaining ECG data for a patient, obtaining a plurality of N-intervals from the ECG data, calculating a plurality of spectral densities based on the plurality of N-N intervals, wherein each spectral density is associated with one of a plurality of successive time windows and is calculated based on certain ones of the N-N intervals associated with the one of the plurality of successive time windows, and generating the graphical representation of sleep quality using the plurality of spectral densities.

Abstract: Systems and methods are provided to display discrete conduction timing values of layers of the ventricles. Electrical impulses are detected using two or more electrodes placed proximate to a beating heart and are converted to an ECG waveform for each heartbeat of the beating heart. One or more subwaveforms within Q, R, S, and T waveforms of the ECG waveform for each heartbeat or in an interval between the Q, R, S, and T waveforms are detected that represent the depolarization or repolarization of anatomically distinct layers of the ventricles of the beating heart. A conduction timing value is calculated for each of the one or more subwaveforms for each electrode of the two or more electrodes for each heartbeat of the beating heart. At least one conduction timing value is displayed for at least one subwaveform for each electrode for at least one heartbeat of the beating heart.

Abstract: Systems and methods are provided to detect a multi-domain ECG waveform. Electrical impulses are detected between at least one pair of electrodes of two or more electrodes placed proximate to a beating heart and are converted to an ECG waveform for each heartbeat of the beating heart. The ECG waveform for at least one heartbeat is received from the detector, the ECG waveform is converted to a frequency domain waveform, the frequency domain waveform is separated into two or more different frequency domain waveforms using two or more different bandpass filters, and the two or more different frequency domain waveforms are converted into two or more different time domain waveforms. The two or more different time domain waveforms are displayed in the same time domain plot as a multi-domain ECG waveform for the at least one heartbeat.

Abstract: Far field reduction is carried out in a cardiac electrogram by extracting unipolar beats of an intracardiac electrogram that occur within a predetermined time interval that includes QRS peaks, constructing a first mean unipolar beat by averaging the extracted unipolar beats, and accepting unipolar beats that cross-correlate with the first mean unipolar beat. A second mean unipolar beat is constructed from the accepted unipolar beats. A ventricular far field component is determined from the extracted unipolar beats and subtracted from the intracardiac electrogram to distinguish a local component of the intracardiac electrogram.

Abstract: An absentminded state determination apparatus includes: a data obtaining element for obtaining a time series data of a physiological characteristic value of a participant, wherein a fluctuation component is overlapped on the time series data, and depends on a state of the participant including normal and absentminded states; a detection element for detecting reflecting portions of the time series data, which reflect on the fluctuation component; a counting element for counting the number of the reflecting portions of the time series data in a determination time period between a determination time and a certain past time; and a determination element for determining according to the number of the reflecting portions at the determination time whether the participant is in the absentminded state. The determination time period has a predetermined time width from the certain past time to the determination time.