Abstract: An apparatus and method for determining a signal quality of an input signal representing a repetitious phenomena derived from at least one sensor connected to a patient is provided. A detector receives the input signal and determines data representing the repetitious phenomena from the input signal for use in determining at least one patient parameter. A measurement processor is electrically coupled to the detector that determines a first signal quality value by identifying at least one feature of the repetitious phenomena data and compares the at least one feature of a first set of the determined repetitious phenomena data with a second set of the determined repetitious phenomena data to determine a feature variability value and using the feature variability value to determine a stability value representative of the quality of the input signal.

Abstract: A subject information detecting unit I1 includes a sensor mount I21, having an opening I22 at a portion to be in contact with a subject I91 and an internal cavity I23 communicated with the opening I22, the cavity defining a closed spatial structure in a state where the subject information detecting unit I1 is mounted on the subject such that the opening I22 faces the subject I91; a sensor I31 disposed on the sensor mount I21 and receiving pressure information deriving from pulsating signals in a blood vessel I92 in the subject I91, the sensor detecting the pulsating signals in the blood vessel in the subject; and a film member I11 separating the opening I22 from the sensor I31 and blocking the permeation of moisture. The sensor I31 detects the pressure information deriving from pulsating signals from the blood vessel I92 in the subject I91 and propagating through the opening I22, the cavity I23 and the film member I11.

Abstract: Provided is a non-invasive system for estimating an atrial signal, including a plurality of sensors to sense a surface electrocardiogram signal, a reference atrial signal generation unit to generate an estimated ventricular signal with respect to a R wave in an electrocardiogram signal from one sensor among the plurality of sensors, and to generate a reference atrial signal by subtracting the estimated ventricular signal from the electrocardiogram signal from the one sensor, and an atrial signal estimation unit to generate an estimated atrial signal by applying a constrained independent component analysis algorithm based on the reference atrial signal to the received surface electrocardiogram signal, and to estimate one of the estimated atrial signals as an actual atrial signal, and a method using the same.

Abstract: Disclosed herein are various embodiments of methods, systems and devices for detecting atrial fibrillation (AF) in a patient. According to one embodiment, a hand-held atrial fibrillation detection device acquires an electrocardiogram (ECG) from the patient over a predetermined period of time. After acquiring the ECG from the patient, the device processes and analyzes the ECG and makes a determination of whether or not the patient has AF.

Abstract: A method for determining the signal quality of samples in a physiological signal, in particular an electrocardiogram (ECG) signal, is provided. A supra-threshold sample sum, a noise threshold crossing sum, or both are calculated in a noise detection window including the sample to be evaluated, and low signal quality is indicated if either or both of the sums exceed respective values. ECG beat detections can then be labeled as unreliable based on the determination of low signal quality for one or more samples between the detections.

Abstract: A cardiac device and method for detecting QRS signals within a composite heart signal of a body including providing at least two input heart signals via at least two separate input channels, wherein each of the at least two input heart signals is recorded by pairs of sensing electrodes that have one electrode in common and provided coincidental in time. The cardiac device and method include generating estimated signals from the input heart signals, combining the input heart signals and the estimated signals to a combined input stream (SECG), and detecting the QRS signal by comparing the combined input stream (SECG) to an adaptive detection threshold (ATHR) which adapts throughout time.

Abstract: A method for graphical representation of a train of ECG complexes having an R wave and a T-P interval and having variable isoelectric baselines. The method involves aligning the complexes in terms of signal amplitude by obtaining a baseline, thereby to provide a graphical representation of said train of ECG complexes; and aligning said complexes temporally using corresponding predetermined points.

Abstract: A method for detecting an R-wave from an ECG signal derived from a living body, the ECG signal including a plurality of ECG channel signals, the method comprising the steps of providing a plurality of channel R-wave detectors each processing a distinct signal of the plurality of channel ECG signals to generate a distinct channel trigger signal of a plurality of channel trigger signals, and inputting each channel trigger signal into a composite R-wave detector to generate a composite R-wave trigger, whereby the composite R-wave detector more accurately detects R-waves than each of the plurality of channel R-wave detectors.

Abstract: An active implantable medical device (e.g., implantable pacemaker or defibrillator), for detection of QRS complexes in noisy signals. Functional units (12-16) collect, amplify, prefilter and convert from analog-to-digital an endocardial signal, and digital functional units (18) provide signal processing and analysis of the digitized signal, for delivery of an indicator corresponding to a signal peak detection representative of the presence of a QRS complex in the endocardial signal. A double threshold comparator (30) is employed, receiving as input (28) the digitized signal and outputting (40) the indicator of peak detection when, cumulatively: the amplitude (A) of the input signal exceeds a peak amplitude threshold (SA), and the peak amplitude threshold is exceeded for a period (W) greater than a peak width threshold (SW). The peak amplitude threshold (SA) is a variable adaptive threshold, according to a noise level calculated from the energy (RMS) of the input signal.

Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to perform arrhythmia discrimination. A plurality of different sensing vectors are used to obtain a plurality of different IEGMs, each of which is indicative of cardiac electrical activity at a different ventricular region. The plurality of different IEGMs can include, e.g., an IEGM indicative of cardiac electrical activity at a first region of the patient's left ventricular (LV) chamber and an IEGM indicative of cardiac electrical activity at a second region of the patient's LV chamber. Additionally, the plurality of different IEGMs can further include an IEGM indicative of cardiac electrical activity at a region of a patient's right ventricular (RV) chamber. For each of the IEGMs, there is a determination of a corresponding localized R-R interval stability metric indicative of the R-R interval stability at the corresponding ventricular region. This can include, e.g.

Abstract: A medical device and associated method for classifying an unknown cardiac signal that includes sensing a cardiac signal over a plurality of cardiac cycles, determining a template of a known cardiac signal in response to the cardiac signal sensed over the plurality of cardiac cycles, sensing an unknown cardiac signal over an unknown cardiac cycle, determining a fourth order difference signal, determining a template alignment point and an unknown cardiac signal alignment point in response to the fourth order difference signal; determining an R-wave onset and an R-wave offset in response to the fourth order difference signal of the unknown cardiac cycle signal, determining an R-wave width as the difference between the R-wave onset and the R-wave offset, determining a morphology analysis window in response to the R-wave width, and determining a first morphology match metric across the morphology analysis window.

Abstract: An electrocardiography signal extraction method includes receiving an electrocardiography signal, detecting a peak of a wave of the electrocardiography signal, separating the wave into left and right waves, normalizing the left wave and a plurality of scales of Gaussian, comparing the normalized left wave with a left part of the normalized scales of Gaussian, acquiring a left part error function, indicating a left minimum comparative error, selecting a left scale of Gaussian with the left minimum comparative error, obtaining a left duration of the wave, normalizing the right wave, comparing the normalized right wave with a right part of the normalized scales of Gaussian, acquiring a right part error function, indicating a right minimum comparative error, selecting a right scale of Gaussian with the right minimum comparative error, obtaining a right duration of the wave, and obtaining an extracted wave.

Abstract: A system automatically detects peaks in signal by generating a zero-mean data sequence of the signal comprising a data sequence and filtering the zero-mean data sequence. The entropy of the filtered data sequence is determined and peaks are detected in the entropy data sequence.

Abstract: An implantable cardioverter defibrillator (ICD) senses ventricular depolarizations (R-waves) in an electrogram signal to detect a ventricular tachycardia or fibrillation episodes. The EGM signal is also monitored in real time for characteristics that uniquely identify instances of T-wave oversensing. The ICD determines whether detection of a tachycardia or fibrillation episode is appropriate based upon counts of each of the unique characteristics evidencing T-wave oversensing.

Abstract: In a mood analysis method using an electrocardiogram of a user, RR intervals in the electrocardiogram are computed, and low-frequency (LF) values and high-frequency (HF) values are also computed according to the RR intervals. Standard values of sympathetic nervous system (SNS) activity and parasympathetic nervous system (PSNS) activity are acquired corresponding to age and sex data of the user, to establish a mood display coordinate system. Coordinates of the LF values and the HF values in the mood display coordinate system are computed to determine a mood of the user.

Abstract: An integrated catheter placement system for accurately placing a catheter within a patient's vasculature is disclosed. In one embodiment, the integrated system comprises a system console, a tip location sensor for temporary placement on the patient's chest, and an ultrasound probe. The tip location sensor senses a magnetic field of a stylet disposed in a lumen of the catheter when the catheter is disposed in the vasculature. The ultrasound probe ultrasonically images a portion of the vasculature prior to introduction of the catheter. ECG signal-based catheter tip guidance is included in the integrated system to enable guidance of the catheter tip to a desired position with respect to a node of the patient's heart. Various aspects for visualizing and manipulating display of the ECG signal data acquired via the present system, together with aspects of various ECG sensor configurations, are also disclosed.

Abstract: A method for graphical representation of a train of ECG complexes having an R wave and a T-P interval and having variable isoelectric baselines. The method involves aligning the complexes in terms of signal amplitude by obtaining a baseline, thereby to provide a graphical representation of said train of ECG complexes; and aligning said complexes temporally using corresponding predetermined points.

Abstract: A method for detecting heart beats within a cardiac signal is disclosed. A cardiac signal is acquired and segmented. Peak detection is performed within each segment. A search within the detected peaks is performed to locate physiologically permissible peak sequences. A particular peak sequence is selected based on feature space criteria or interpeak temporal regularity criteria or both.

Abstract: This biological information processing device is provided with: a peak detection unit for detecting the peaks of a biological signal generated in a cardiac cycle; a waveform clipping unit for clipping out a first peak-to-peak biological signal between two peaks, which are adjacent on the time axis of the biological signal, on the basis of detection results of the peak detection unit; and a resampling unit for transforming the first peak-to-peak biological signal to a second peak-to-peak biological signal for a prescribed number of samples. The biological information processing device is further provided with: an orthogonal transformation unit for generating orthogonal transformation coefficients by performing an orthogonal transformation on the second peak-to-peak biological signal; a differential processing unit for generating a differential signal for the orthogonal transformation coefficients on the time axis; and an encoding unit for encoding the differential signal.

Abstract: A method estimates morphological features of heart beats from an ECG signal. Peaks of the R wave of the ECG are detected and classified using a parallel filtering structure. The first branch implements a bandpass filtering with cut off frequencies of about 10 Hz and 35 Hz, enhancing the signal-to-noise ratio (SNR) of the QRS complex. The second branch estimates morphological features of the heart beat from an alternating current (AC) replica of the ECG signal, that may be used to classify the beat and potentially detect arrhythmias.

Abstract: Methods and devices for addressing difficulty with cardiac event sensing that can arise if the starting point of the cardiac cycle is not well aligned to the intended starting point of a detection profile used for sensing. As an improvement, illustrative methods and devices provide an addition to cardiac sensing operations by adjusting the starting point of a detection profile to align with a desired point in the cardiac signal.

Abstract: A handheld terminal includes an electrocardiographic-signal dividing module that divides a biosignal into waveforms of a fixed interval, an R-R interval calculating module that calculates a plurality of R-R intervals indicative of an interval between adjacent R-waves and calculates an average value of the calculated R-R intervals for each of the waveforms of the fixed interval divided, and a candidate-waveform selecting module that selects a plurality of waveforms of a fixed interval corresponding to average values indicating near a maximum value of frequency of average values using the average value of the R-R intervals calculated for each of the waveforms of the fixed interval calculated, and thus highly accurate representative waveform data can be generated.

Abstract: A system comprises a cardiac signal sensing circuit and a processor circuit. The cardiac signal sensing circuit is configured to sense a cardiac signal segment using a set of electrodes connectable to the cardiac signal sensing circuit. The processor circuit is communicatively coupled to the cardiac signal sensing circuit and includes a peak detector circuit. The peak detector circuit is configured to identify, in the cardiac signal segment, a fiducial indicative of ventricular activation that is local to at least one electrode of the first set of electrodes. The fiducial includes a first large positive or negative peak greater than a specified percentage of a maximum peak of the first cardiac signal segment. The processor circuit is configured to provide an indication of local ventricular activation to at least one of a user or process.

Abstract: A delivery catheter, including a catheter body, a side port, a first electrode, and a second electrode, is described. The catheter body may comprise a proximal end, a distal end, and a perimeter surface. The catheter body defines a delivery lumen extending longitudinally within the catheter body. The side port is defined in the perimeter surface of the catheter body proximate the distal end and in communication with the delivery lumen. The electrodes may be adjacent to and spaced from the side port. Techniques for using the delivery catheter to identify a desired lead implantation location, e.g., via the electrodes, and implant a medical lead or other implantable element at the desired location through the delivery lumen and side port are also described.

Abstract: An active implantable medical device (e.g., implantable pacemaker or defibrillator), for detection of QRS complexes in noisy signals. Functional units (12-16) collect, amplify, prefilter and convert from analog-to-digital an endocardial signal, and digital functional units (18) provide signal processing and analysis of the digitized signal, for delivery of an indicator corresponding to a signal peak detection representative of the presence of a QRS complex in the endocardial signal. A double threshold comparator (30) is employed, receiving as input (28) the digitized signal and outputting (40) the indicator of peak detection when, cumulatively: the amplitude (A) of the input signal exceeds a peak amplitude threshold (SA), and the peak amplitude threshold is exceeded for a period (W) greater than a peak width threshold (SW). The peak amplitude threshold (SA) is a variable adaptive threshold, according to a noise level calculated from the energy (RMS) of the input signal.

Abstract: A system for adaptively processing patient monitoring signals comprises an input processor for acquiring a signal having amplitude representing electrical activity of a patient heart over time. A signal processor identifies different portions of the signal associated with different phases of cardiac activity by, inverting the signal to provide an inverted signal, aligning the signal and the inverted signal in amplitude during a cardiac rest portion and identifying one or more of the different portions in response to an intersection point of the signal and the inverted signal. Multiple adaptive signal filters are used to filter multiple bandwidths of corresponding different portions of the signal.

Abstract: A method for detecting an R-wave from an ECG signal (x(t)) derived from a living body, the method comprising the steps of (a) acquiring the ECG signal from the living body, (b) digitizing the ECG signal into a digital ECG signal (x(ti)), (c) filtering the digital ECG signal with a bandpass filter (53) and applying an absolute value filter (55) thereto to create a filtered ECG signal (g(ti)), (d) for each sequential value of the filtered ECG signal, comparing (57) the filtered ECG signal to an ECG tracking threshold (TT), (e) if the filtered ECG signal is no greater than TT, incrementing a counter (59), but if greater than TT, setting the counter to zero; and (f) comparing (63) the counter to a predetermined refractory count RC and, if the count is equal to RC, outputting an R-wave trigger indicating that an R-wave has been detected.

Abstract: A monitor of a physiological parameter of subject under test to which the monitor is attached, in operation. The monitor includes a set of accelerometers operating in different ranges of acceleration and a physiological sensor. The physiological sensor may include an ECG circuit producing an output data characterizing the subject as a function of a degree of motion and/or reorientation of the monitor or an oximeter device. The process of monitoring includes a determination of R-wave of the subject.

Abstract: Disclosed herein is a framework for facilitating patient signal analysis. In accordance with one aspect, at least one region of interest within a cycle of a waveform of patient signal data is identified. The identified region of interest may be segmented into portions using amplitude percentage categories. A sequential morphological data series may be generated by compiling time intervals of the segmented portions. One or more sequential signal parameters may be calculated based on the sequential morphological data series. A report may then be generated based at least in part on the one or more sequential signal parameters.

Abstract: A method and a system for determining changes in a body state of an individual including receiving a signal from a monitoring system, where the signal indicates a measurement of cardiac activity of the individual over a period of time and determining at least one signal feature, where the signal feature is a reoccurring event of the signal over the period of time. The method also includes determining a first interval between two successive signal features and determining a second interval between two successive first intervals. A derivative is calculated based on the second interval. Changes in the body state are identified based on the derivative.

Abstract: Embodiments of the present disclosure are configured to collect multi-modality medical data from a patient. In some embodiments, a method includes acquiring heartbeat data from the patient using a heart-monitoring device, the heartbeat data identifying a first cardiac cycle of the patient and selecting a diagnostic window within the first cardiac cycle of the patient, wherein the diagnostic window encompasses only a portion of the first cardiac cycle of the patient. The method also includes acquiring first medical data from the patient during the diagnostic window using a first medical device, the first medical data being associated with a first medical modality and acquiring second medical data from the patient during the diagnostic window using a second medical device, the second medical data being associated with a second medical modality different than the first medical modality.

Abstract: In general, this disclosure is directed to signal processing based methods to reject undersensing in a signal indicative of cardiac activity, e.g., ECG. The undersensing may be due to very small signal amplitudes or due to a sudden increase in single peak amplitude resulting in an increased sensing threshold. The undersensing may result in falsely detecting a cardiac event, e.g., asystole or bradycardia. The techniques of this disclosure monitor the behavior of the signal to determine when a detected asystole is false.

Abstract: A system for determining the Q and J points of an electrocardiogram (ECG) combines a WLT-based Q, J detection algorithm with signal quality assessment for lead selection. A Q, J detector (24) receives a beat-cycle waveform for the beat under consideration from each of a plurality (N) of ECG leads, and assesses signal quality for each lead using signal quality assessor (SQA) components 261, 262 . . . 26N. The leads with “good” signal qualities are employed for a multichannel waveform length transform (WLT), which yields a combined waveform length signal (CWLS). The Q and J points are then determined from the CWLS.

Abstract: A method for detecting an R-wave from an ECG signal derived from a living body, the ECG signal including a plurality of ECG channel signals, the method comprising the steps of providing a plurality of channel R-wave detectors each processing a distinct signal of the plurality of channel ECG signals to generate a distinct channel trigger signal of a plurality of channel trigger signals, and inputting each channel trigger signal into a composite R-wave detector to generate a composite R-wave trigger, whereby the composite R-wave detector more accurately detects R-waves than each of the plurality of channel R-wave detectors.

Abstract: An exemplary electronic device is in a housing to be gripped by a right hand and a left hand of a user, and has a plurality of manipulable portions. The electronic device includes: electrodes placed at positions which come in contact with the right hand and left hand of the user gripping the housing; an extractor for extracting an electrocardiographic component of the user from a potential difference between the electrodes; a determination section for determining whether the extracted electrocardiographic component is in a positive direction or a negative direction by referring to a prestored criterion; and a change section for, in accordance with a result of determination by the determination section, changing assignment between each of the plurality of manipulable portions and a manipulation signal generated in response to a manipulation.

Abstract: A medical device and associated method for classifying an unknown cardiac signal operate to sense a cardiac signal over known cardiac cycles and generate a template of the known cardiac cycles. An unknown cardiac signal is sensed over an unknown cardiac cycle. A template alignment point and an unknown cardiac signal alignment point are identified by using a fourth order difference signal. The template and the unknown cardiac signal are aligned across an alignment window by aligning the template alignment point and the unknown cardiac signal alignment point. A morphology match metric measuring a similarity between the aligned template and the unknown cardiac signal is computed.

Abstract: A cardiac device and method for detecting QRS signals within a composite heart signal of a body including providing at least two input heart signals via at least two separate input channels, wherein each of the at least two input heart signals is recorded by pairs of sensing electrodes that have one electrode in common and provided coincidental in time. The cardiac device and method include generating estimated signals from the input heart signals, combining the input heart signals and the estimated signals to a combined input stream (SECG), and detecting the QRS signal by comparing the combined input stream (SECG) to an adaptive detection threshold (ATHR) which adapts throughout time.

Abstract: A cardiac-activity based prediction of a rapid drop in a patient's blood pressure during extracorporeal blood treatment is disclosed. A proposed alarm apparatus includes a primary beat morphology analysis unit bank of secondary analysis units and an alarm generating unit. The primary beat morphology analysis unit discriminates heart beats in a received basic electrocardiogram signal, classifies each beat into one out of at least two different beat categories, and associates each segment of the signal with relevant event-type data. The event-type data and the basic electrocardiogram signal together form an enhanced electrocardiogram signal, based upon which the primary beat morphology analysis unit determines whether one or more secondary signal analyses should be performed.

Abstract: A method for mapping a cardiac chamber includes sensing activation signals of intrinsic physiological activity with a plurality of electrodes disposed in or near the cardiac chamber, the activation signals including a near-field activation signal component and a far-field activation signal component, isolating R-wave events in the activation signals, generating a far-field activation template representative of the far-field activation signal component based on the R-wave events, and filtering the far-field activation template from the activation signals to identify the near-field activation signal components in the activation signals.

Abstract: One or more embodiments of the present disclosure relates to a method and/or system for classifying and/or treating heart rhythms. The present disclosure involves sensing electrical signals associated with depolarizations of a patient's heart. The sensed electrical signals are converted to digital values and storing the digital values. Normalizing solely a maximum and a minimum value of the stored digital values associated with a depolarization of the patient's heart without normalizing other stored digital values of the depolarization is another aspect of the present disclosure. The maximum and minimum values associated with the depolarization are compared to maximum and minimum values associated with a template derived from signals indicative of a heart depolarization of known type. A determination is made as to whether a match exists between the maximum and minimum values associated with the depolarization to the maximum and minimum values associated with a template.

Abstract: A heartbeat signal processor includes a first and second electrodes to obtain a first and second heartbeat signals, a DC voltage calculating unit and an AC amplitude calculating unit to calculate first and second average DC voltage values of direct-current components and first and second average AC amplitude values of alternate-current components in the first and second heartbeat signals, a correlation coefficient calculating unit to calculate a correlation coefficient between the alternate-current components in the first and second heartbeat signals, an amplification factor setting unit to set an amplification factor on the basis of the first and second average DC voltage values, the first and second average AC amplitude values, and the correlation coefficient, and a signal generating unit to generate a differential heartbeat signal by amplifying the first or second heartbeat signal on the basis of the amplification factor and calculating a difference between the first and second heartbeat signals.

Abstract: A mobile system for analyzing ECG data includes an analog front end module coupled to a mobile consumer device. The analog front end module is configured to collect ECG data from one or more leads and is operable to convert the analog ECG data to digital ECG data. The mobile consumer device is coupled to receive the digital ECG data, and is configured to perform QRS detection using a filter whose cutoff frequency is adapted to noise level in real time. The ECG signal is amplified non-linearly and three windowed threshold signals (D, E, J) are derived. The cutoff frequency for the QRS detection is dynamically selected as a function of the threshold signals. A sample in the amplified signal is identified to be a heart beat point only when the sample value is equal to the first threshold signal and greater than the filtered threshold signal.

Abstract: A circuit and method for long term electrocardiogram (ECG) monitoring is implemented with the goal of reducing power consumption, battery size, and consequently device size. In one embodiment, the integrated circuit includes an amplifier cell having a plurality of input terminals and an output terminal; a QRS amplifier cell in communication with the output of the amplifier cell; a baseline amplifier cell in communication with the output of the amplifier cell; a comparator cell having a first input terminal in communication with the output terminal of the QRS amplifier cell; and a VDC cell having an input in communication with the output of the baseline amplifier cell and an output in communication with the second input terminal of the comparator cell, wherein the comparator cell generates an output pulse in response to the output signal from the amplifier cell and the output signal from the baseline amplifier cell.

Abstract: Methods, systems, and apparatus for quantifying the quality of a fiducial time marker for a candidate heart beat, quantifying the quality of a candidate heart beat, or determining a time of beat sequence of the patient's heart. A fiducial time marker is obtained for a candidate heart beat. A quality index of said candidate heart beat is set to a first value. The candidate heart beat is tested with at least one beat validity test. At least a second value is added to said quality index of said candidate heart beat if said candidate heart beat passes said at least one beat validity test. The candidate heart beat is tested with at least a second heart beat validity test. At least a third value is added to said quality index of said candidate heart beat if said candidate heart beat passes said at least second heart beat validity test.

Abstract: A system and method for distinguishing an epileptic event from a syncope event that includes sensing a signal, generating sensed intervals in response to the sensed signal, generating an indication signal in response to an occurrence of an event, determining a marginality in response to the generated indication signal and the sensed intervals, and determining the event as being one of the epileptic event and the syncope event in response to the determined marginality.

Abstract: The invention provides a sleep apnea detection system and method. The system includes a detecting module, a processing module, a converting module and a determining module. The detecting module detects a plurality of peak time points of R-waves in an ECG (electrocardiograph) signal. The processing module calculates areas of the R-waves at a predetermined time range based on the peak time points, so as to produce a plurality of first R-wave area signals based on the areas and generate an EDR (ECG Derived Respiration) signal based on the peak time points and the first R-wave area signals. The converting module converts the EDR signal to a frequency signal. The determining module determines whether a maximum peak frequency of the frequency signal is at a first frequency segment or a second frequency segment to determine the frequency signal being an apnea signal or a normal breathing signal.

Abstract: Apparatuses and methods for extracting, de-noising, and analyzing electrocardiogram signals. Any of the apparatuses described herein may be implemented as a (or as part of a) computerized system. For example, described herein are apparatuses and methods of using them or performing the methods, for extracting and/or de-noising ECG signals from a starting signal. Also described herein are apparatuses and methods for analyzing an ECG signal, for example, to generate one or more indicators or markers of cardiac fitness, including in particular indicators of atrial fibrillation. Described herein are apparatuses and method for determining if a patient is experiencing a cardiac event, such as an arrhythmia.

Abstract: Technologies are provided herein for real-time detection of motion and noise (MN) artifacts in electrocardiogram signals recorded by electrocardiography devices. Specifically, the present disclosure provides techniques for increasing the accuracy of identifying paroxysmal atrial fibrillation (AF) rhythms, which are often measured via such devices. According to aspects of the present disclosure, a method for detecting MN artifacts in an electrocardiogram (ECG) recording includes receiving an ECG segment and decomposing the received ECG segment into a sum of intrinsic mode functions. The intrinsic mode functions associated with MN artifacts present within the ECG segment are then isolated. The method further includes determining randomness and variability characteristic values associated with the isolated intrinsic mode functions and comparing the randomness and variability characteristic values to threshold randomness and variability characteristic values.

Abstract: A method and system for measuring psychological stress disclosed. In a first aspect, the method comprises determining R-R intervals from an electrocardiogram (ECG) to calculate a standard deviation of the R-R intervals (SDNN) and determining a stress feature (SF) using the SDNN. In response to reaching a threshold, the method includes performing adaptation to update a probability mass function (PMF). The method includes determining a stress level (SL) using the SF and the updated PMF to continuously measure the psychological stress. 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: The present invention provides an improved, Internet-based system that seamlessly collects cardiovascular data from a patient before, during, and after a procedure for EP or an ID. During an EP procedure, the system collects information describing the patient's response to PES and the ablation process, ECG waveforms and their various features, HR and other vital signs, HR variability, cardiac arrhythmias, patient demographics, and patient outcomes. Once these data are collected, the system stores them on an Internet-accessible computer system that can deploy a collection of user-selected and custom-developed algorithms. Before and after the procedure, the system also integrates with body-worn and/or programmers that interrogate implanted devices to collect similar data while the patient is either ambulatory, or in a clinic associated with the hospital. A data-collection/storage module, featuring database interface, stores physiological and procedural information measured from the patient.