Abstract: A patient management system is described that includes an implantable device for collecting one or more physiological parameter values and associated timestamps indicating the time at which the value is collected. The system is then configured to determine the periodic variation, if any, of a particular physiological parameter and use that periodicity in assessing changes in the parameter values over time.

Abstract: An apparatus, a method and a computer program for the determination of sympathetic activity are disclosed. The method comprises: receiving heart activity data of a person; determining a recovery heart rate change speed during a recovery heart rate period in the heart activity data; and determining a sympathetic activity state of the sympathetic nervous system of the person based on the determined recovery heart rate change speed.

Abstract: Implantable systems, and methods for use therein, perform at least one of a cardiac assessment and an autonomic assessment. Premature atrial contractions (PACs) are induced to thereby cause corresponding premature contractions in the ventricles. Short-term fluctuations in cardiac intervals, that follow the premature contractions in the ventricles caused by the induced PACs, are monitored. At least one of a cardiac assessment and an autonomic assessment is performed based on the monitored fluctuations in cardiac intervals that follow the premature contractions in the ventricles caused by the induced PACs. This can include assessing a patient's risk of sudden cardiac death (SCD), assessing a patient's autonomic tone and/or detecting myocardial ischemic events based on the monitored fluctuations in cardiac intervals that follow the premature contractions in the ventricles caused by the induced PACs.

Abstract: Disclosed herein are an apparatus and method to detect a heart-rate and an air conditioning system having the apparatus. As peak points of vital signs acquired from a user are detected via determination of a period, a reliable heart rate variability is calculated based on the peak points. As the emotional state of the user can be diagnosed based on vital signs of the user, optimal air-conditioning control according to physical characteristics or emotional state of the user can be accomplished by sequentially controlling a variety of air-conditioning control factors according to the priority thereof until the user becomes comfortable.

Abstract: One of the objects of the present invention is to provide an system which can detects degradation in a driving mental state of a driver, that is, sleepiness, fatigue, fret, and so on during driving of a vehicle and notifies the driver of the degradation to encourage safe driving and can reproduce sound such as music matching the taste of the user such as a driver while maintaining awakening of the driver of a mobile unit.

Abstract: A “tracker system” that includes electrical leads which are part of an implanted cardiotracker plus external equipment that includes external alarm and a physician's programmer. The tracker system is designed to monitor the degradation of a patient's cardiovascular condition from one or more causes, These causes include the rejection of a transplanted heart and/or the progression of a stenosis in a coronary artery. As one or more stenoses in a coronary artery become progressively more narrow thereby causing reduced blood flow to the heart muscle coronary circulation, the tracker system can alert the patient by either or both internal and/or external alarm to take the appropriate medical action. The physician's programmer can be used to display histograms of key heart signal parameters that are indicative of the patient's cardiovascular condition.

Abstract: A monitor device and associated methodology are disclosed which provide a self contained, relatively small and continuously wearable package for the monitoring of heart related parameters, including ECG. The detection of heart related parameters is predicated on the location of inequipotential signals located within regions of the human body conventionally defined as equivalent for the purpose of detection of heart related electrical activity, such as on single limbs. Amplification, filtering and processing methods and apparatus are described in conjunction with analytical tools for beat detection and display.

Abstract: A computationally efficient method for assessing a subject's autonomic balance by measurement of heart rate variability is disclosed which is particularly suitable for implementation by an implantable medical device. Statistical surrogates are used to represent frequency components of an RR time series. A ratio of the low frequency component to the high frequency component may then be estimated to assess the subject's autonomic balance.

Abstract: A wrist-worn or arm band worn heart rate variability monitor is provided. Heart rate variability (“HRV”) refers to the variability of the time interval between heartbeats and is a reflection of an individual's current health status. Over time, an individual may use the results of HRV tests to monitor either improvement or deterioration of specific health issues. Thus, one use of the HRV test is as a medical motivator. When an individual has a poor HRV result, it is an indicator that they should consult their physician and make appropriate changes where applicable to improve their health. If an individual's HRV results deviate significantly from their normal HRV, they may be motivated to consult their physician. In addition, the inventive monitor is capable of monitoring the stages of sleep by changes in the heart rate variability and can record the sleep (or rest) sessions with the resulting data accessible by the user or other interested parties.

Abstract: Apparatus for measuring a user's heart rate and other physiological parameters derived from two electrodes at least one of which is in contact with the user's head. The second electrode is in contact with the user's skin. A heart rate detection circuit is coupled to the electrodes to detect the user's heart rate as electrical potential difference between the first and second electrodes. The electrodes may be integral with user apparel such as hats, headbands, helmets, eyewear, etc. The electrodes may be integral with headphone speakers in contact with the user's ears. The heart rate detection circuit may be integral with or coupled to an audio source device such as an MP3 player or a portable communication device. The detected heart rate may be presented to the user as audio signals or as visually displayed information. A third electrode may be added to improve the quality of the sensed signals.

Abstract: Heart monitor signals indicating a patient's heart characteristics are amplified without affecting the signal characteristics. The amplified heart monitor signals with atypical characteristics are transmitted to a pattern recognition platform which stores the patient's previously provided signals with atypical characteristics. The patient's present and previously provided signals with atypical characteristics are compared to select the previously provided signals with characteristics closest to those of the presently provided signals. Database signals identifying different types of heart problems in third parties and having characteristics closest to the patient's selected atypical signals are chosen. Dependent upon the severity of the patient's heart problems identified by the chosen database signals, the monitor transmits the chosen database signals to an individual one of the patient's doctor, the patient's hospital and an emergency care facility.

Abstract: A wristop heart rate monitor comprising a dial, which comprises a current heart rate indicator, which is responsive to a heart rate signal measured from a user of the wristop heart rate monitor and functionally connected to a heart rate scale, and a reference indicator defining a visually identifiable reference heart rate range. At least one of the indicators is rotatably adjustable relative to the dial, and the heart rate scale and the reference heart rate range are adjustable relative to each other. A method is also described for monitoring the heart rate of a sportsman. The wristop heart rate monitor provides a quickly perceivable and adjustable heart rate monitor structure.

Abstract: A method and device for heart rate measurement uses a stream of signals containing ECG signals to select a reference QRS complex according to a set of predetermined criteria and obtain electrical signal characteristics of the reference QRS complex. A first QRS complex is detected from the stream of signals and characterized in relation to the reference QRS in the time domain such that the first QRS complex meets another set of predetermined criteria, and satisfies a level of similarity with the reference QRS complex. An instantaneous heart rate of a subject is evaluated based on the first and the reference QRS complexes when the first and the second QRS complexes are sufficiently similar.

Abstract: Techniques are provided for tracking patient respiration based upon intracardiac electrogram (IEGM) signals or other electrical cardiac signals. Briefly, respiration patterns are detected based upon cycle-to-cycle changes in morphological features associated with individual electrical events with the IEGM signals. For example, slight changes in the peak amplitudes of QRS-complexes, P-waves or T-waves are tracked to identify cyclical variations representative of patient respiration. Alternatively, the integrals of the morphological features of the individual events may be calculated for use in tracking respiration. In any case, once respiration patterns have been identified, episodes of abnormal respiration, such as apnea, hyperpnea, nocturnal asthma, or the like, may be detected and therapy automatically delivered. In particular, techniques for detecting abnormal respiration based on various respiratory parameters derived from the IEGM—such as respiration depth and respiration power—are described.

Abstract: Described is a motivational fitness device, which controls the audio output of a television or audio component in response to the heart rate. The user must exercise in their specific heart rate target training range to keep their entertainment device turned on at an enjoyable volume. A heart rate sensing device relays heart rate to a processor unit. The processor receives and compares the user's heart rate to the specified target range and sends control signals (or not) to the entertainment device. If the user's heart rate drops below the target range, the volume of the audio output of their entertainment device will gradually decrease until the user reacquires their target. Conversely, if the user is exercising too vigorously, the volume will increase, motivating the user to reacquire their target heart rate range.

Abstract: A method of determining the location in time of maxima and/or minima of an oscillatory signal. The method may have application to measurement of biological signals, in particular measurement of heart rate from a pulsatile blood signal. The method includes a first stage including the steps of observation over a measurement period, identifying large local maxima or minima and computing an average interval between the identified local maxima or minima. One or more exclusion periods are located in time in the oscillatory signal, having a duration dependent on the average interval, the exclusion periods used to reject false maxima or minima. Maxima or minima may also be detected as an absolute maximum or minimum between crossing points of a fast and a slow moving average of the oscillatory signal. An exclusion period may also be used to reject false maxima or minima when crossing points are used. Apparatus for performing the method is also claimed.

Abstract: An implantable cardioverter/defibrillator (ICD) executes a rate accuracy enhancement algorithm to select measured atrial and ventricular intervals for classifying a detected tachycardia based on average atrial and ventricular rates calculated from the selected atrial and ventricular intervals. The detected tachycardia is classified as ventricular tachycardia (VT) if the average ventricular rate is substantially higher than the average atrial rate.

Abstract: A procedure for the detection of stress state is disclosed, wherein ambulatory heart beat signal is measured. In the first phase segments are defined from heart beat signal with a chosen rule for segmentation. Then at least one segment describing a physiological state with elevated cardiac activity due to physical workload and/or increased metabolic rate is identified and excluded, if exists, and segments other than the excluded segments are detected for a potential stress state, which is identified using a predetermined rule for the heart beat signal.

Abstract: A method of predicting an arrhythmia, such as ventricular tachycardia, for example, in a medical device using a quantitative measure in order to allow assessment of patient risk and to enable preventative interventions by the device and clinicians. The trending of day and night average heart rates, along with patient physical activity can be analyzed to provide prediction of impending arrhythmia within weeks. By examining day and night average heart rate for crossover points, where the night heart rate equals or exceeds the day rate, and monitoring for a concomitant elevation in the night heart rate from a reference value, specific days heralding an increased risk of arrhythmia can be determined and therapy can be updated accordingly.

Abstract: An electronic device and method includes a means for setting a time interval for collecting a set of physiological data and entering the number of physiological events that occur within that time interval. The device and method are further configured to calculate the number events that occurred per minute, and displays the results for the user. The device may be implemented as a hand-held device and the method implemented in a graphical user interface of an electronic device.

Abstract: This invention relates to a wireless ear-clips heart rate monitor comprising a sensor unit of ear-clips type that detects a user's heart rate, a signal-processing unit that receives and processes the signal generated from the sensor unit, and a wireless signal-transmitting unit that receives the signals from the signal-processing unit and then transmits the signals out. The sensor unit detects frequency of change of blood density to derive heart rate, with the features of precision and efficiency on the detection of heart rate, cooperating with the technique of wireless transmission, the purpose of promoting accuracy of detection and improving convenience of using is attained.

Abstract: An implantable cardiac device is configured and programmed to assess a patient's cardiopulmonary function by evaluating the patient's heart rate response. Such evaluation may be performed by computing a heart rate response slope, defined as the ratio of an incremental change in intrinsic heart rate to an incremental change in measured activity level. The heart rate response slope may then be compared with a normal range to assess the patient's functional status.

Abstract: A method and an arrangement for predicting perioperative myocardial ischemia. Heart rate measurements are carried out for example at night- and day-time before the operation to obtain heart rate data. The heart rate data obtained is carried to a device configured to carry out heart rate variability analysis (HRV). Dynamic heart rate variability analysis is carried out by utilizing fractal analysis of the heart rate data and fractal correlation properties obtained from the measured heart rate data are examined to find considerable lowering of the fractal correlation properties during for example night-time when compared to day-time.

Abstract: A sleepiness level detection device detects a heartbeat signal when a time equal to or longer than T1 and equal to or shorter than T2 has elapsed since the start of driving. The heartbeat signal is subjected to FFT processing to obtain a spectrum signal. By use of a peak frequency of the spectrum signal, a driver conscious-state peak frequency is estimated. A consciousness level index band ? is set with respect to the conscious-state peak frequency. A sleepiness level index band ? is set with respect to a frequency, which is calculated by multiplying the conscious-state peak frequency by a predetermined ratio (65 to 90%). A sleepiness level evaluation parameter Sp (=?p/(?p+?p)) for indicating the sleepiness level of the driver is calculated with the use of the strength ?p and ?p of spectrum signals.

Abstract: The invention relates to an arrangement for coding heart rate information, comprising means (600A, 600B) for measuring a person's heart beat intervals and means for storing (648) the measured heart beat interval information. The arrangement comprises means (654) for coding the heart beat interval information stored in the storing means (648) into music, the coding means comprising means (660) for selecting the rhythm of the music on the basis of the measured heart beat intervals.

Abstract: Methods and apparatus for determining T-wave alternan signatures (i.e., morphology and polarity) derived from a physiologic signal representative of a subject's heart activity; assessing changes in the myocardium Action Potential (“AP”) through analysis of the alternan signature derived from a physiologic signal representative of a subject's heart activity; and/or assessing spatial disassociation of alternan characteristics that are likely associated with the initiation of re-entrant arrhythmias.

Abstract: A system and a method for monitoring a physiological parameter of a patient providing a measurement-modulated acoustic signal (7) after/when a measurement value of the monitored physiological parameter exceeds an alarm limit.

Abstract: A method for analyzing an EKG signal in real time to produce a heart rate indication. The most recent digitized samples of the EKG are stored in a buffer and evaluated to identify each R-wave peak sample value that (a) immediately precedes and is larger that the most recently stored digital sample value, (b) is larger than any other sample value in the buffer, and (c) differs from the first sample value in the buffer by more than a predetermined threshold value. The threshold is a fraction of the rise time slope of the last peak. The real time heart rate indication is calculated from the time duration separating the last two detected peaks, but rate indications outside the range of 30–200 beats per minute, and which depart from the preceding rate indication by more than 50 percent, are discarded.

Abstract: While detecting a missing section from a biological signal acquired from a human body and while storing the biological signal values obtained at n (where n is a natural number) consecutive points in time, weighted addition is conducted on the biological signal values obtained at n points in time. In outputting its result as a final biological signal, the biological signal value at each of points in time included in the missing section is changed to an average value of the biological signal values at points in time which are not in the missing section.

Abstract: A method of assessing the cardiac arrhythmia risk in a subject to provide a measure of cardiac or cardiovascular health in that subject is described herein. In one embodiment, the method comprises the steps of: (a) collecting at least one QT and RR interval data set from the subject; (b) separating fluctuations from slow trends in said at least one QT and RR interval data set; (c) comparing said QT and RR fluctuations to one another and (d) generating from the comparison of step (c) partial measures of risk of cardiac arrhythmia in said subject. A greater difference between QT and RR fluctuations indicates greater risk of cardiac arrhythmia in said subject. The data sets are collected in such a manner that they reflect almost exclusively the conduction in the heart muscle and minimize the effect on the data sets of rapid transients due to autonomic nervous system and hormonal control.

Abstract: Determining termination of an identified tachyarrhythmia episode may involve analysis of a relative decrease in tachyarrhythmia rate, a normalization of electrogram morphology criteria, or both. An implanted medical device may obtain a tachyarrhythmia rate and a morphology of a cardiac waveform. The device may compare the tachyarrhythmia rate to a threshold tachyarrhythmia rate and the morphology to a template morphology, and classify the heart beat as indicating termination of the tachyarrhythmia episode when the tachyarrhythmia rate is less than the threshold tachyarrhythmia rate, the morphology categorizes as normal, or both. For arrhythmias with no therapy delivered, observation of arrhythmia behavior at the point of termination may lead to improved classification. In addition, observation of a relative decrease in tachyarrhythmia rate immediately after therapy application can lead to application of slower but more specific criteria for redetection.

Abstract: A computationally efficient method for assessing a subject's autonomic balance by measurement of heart rate variability is disclosed which is particularly suitable for implementation by an implantable medical device. Statistical surrogates are used to represent frequency components of an RR time series. A ratio of the low frequency component to the high frequency component may then be estimated to assess the subject's autonomic balance.

Abstract: A method and arrangement for estimating a stress level dependent parameter on a person that measures a person's heart rate, calculates a derivative of the measured heart rate, and estimates a value for a stress level dependent parameter by using the calculated heart rate derivative.

Abstract: A device, such as an implantable cardiac device, and methods for determining heart rate recovery of a patient after exercise. Specifically, the method includes identifying a first heart rate indicative of exercise, a second heart rate indicative of a slow-down in exercise, and using the first and second heart rates to determine a measure of heart rate recovery. The first heart rate may be identified when a heart rate measurement and/or an activity level exceeds a predetermined threshold. The second heart rate may be identified based when a heart rate measurement and/or the activity level falls below a predetermined threshold. The device includes hardware and/or software for performing the described methods.

Abstract: A device, such as an implantable cardiac device, and methods for determining exercise diagnostic parameters of a patient are disclosed. Specifically, a maximum observed heart rate of a patient during exercise can be identified when an activity level and a heart rate measurement of the patient exceed predetermined thresholds. Included are methods for filtering out premature heartbeats or noise from the maximum heart rate determination. Methods of determining other exercise parameters, such as workload are also disclosed. The device includes hardware and/or software for performing the described methods.

Abstract: Multiple morphology templates for discliminating between rhythms have been used, such as supraventricular tachyarrhythmias (SVTs) and ventricular tachyarrhythmias (VTs), for delivering a countershock in response to a VT episode, but withholding delivery of such a countershock in response to an SVT episode. In certain examples, the particular morphology used for storing morphological features is selected at least in part using a sensor-indicated activity level of a subject, or a metabolic need of the subject.

Abstract: Systems and methods for assessing an individual's physiological condition are provided. Cycle and shape parameters are derived from a recorded time trace containing heart rate data collected while an individual performs a cyclic exercise routine. Individually tailored exercise regimens that are based on these parameters are generated and modified as desired.

Abstract: A programmable signal analysis device for detecting and counting neurological and muscular events in living tissue that incorporates one or more signal threshold levels to identify an event, a counter to count events, and a timer to determine event frequency as events per unit time. The threshold levels and counter/timer operating modes/parameters are digitally programmable to identify and count events, i.e., electrical signals having defined parameters. Such a circuit is of particular use in a microstimulator/sensor which is capable of being injected into living tissue at the site of interest. The microstimulator/sensor is used to stimulate a neural pathway or muscle and/or to block a neural pathway to alleviate pain or block stimulation of a muscle.

Abstract: A method and apparatus to detect irregular heart activity and estimate heart rate. In one embodiment, the heart rate estimation apparatus includes a group of six RR storage structures that receives an input of six successive RR interval values. The apparatus also includes a probability engine coupled to the group of RR storage structures, the probability engine is operable to calculate and output a mean value of the six RR interval values and a median value of the mean value and the six RR interval. In one embodiment, the apparatus carries out a method including the acts of determining a plurality of interval values between successive R waves; determining a mean of a group of six interval values; determining a median interval value for a group including the group of six interval values and the mean of the group of six interval values; and determining a running average of interval values between successive R waves using the median interval value.

Abstract: Methods and systems for monitoring heart rate recovery are described. In one embodiment, an implantable monitoring device monitors a patient's heart activity. The monitor looks for periods of increased activity, such as those that are experienced during some level of exercise, and periods of lesser activity (such as rest) directly following. The patient's heart rate recovery is monitored as the heart recovers from the active period to the rest period. Data associated with the patient's heart rate recovery can then be diagnostically used to ascertain certain conditions associated with the patient.

Abstract: A system for selecting physiological data from a plurality of physiological data sources includes first and second physiological data sources and a selection algorithm. The first physiological data source is configured to provide first physiological data. The first physiological data includes a first measurement of a physiological trait. The second physiological data source is configured to provide second physiological data. The second physiological data includes a second measurement of the physiological trait. The first and second measurements are based on different physiological characteristics. The selection algorithm is configured to receive the first and second physiological data and to select one of the first and second measurements as the output data for the physiological trait based on at least one of the first physiological data and the second physiological data.

Abstract: A method for analyzing an EKG signal in real time to produce a heart rate indication. The most recent digitized samples of the EKG are stored in a buffer and evaluated to identify each R-wave peak sample value that (a) immediately precedes and is larger that the most recently stored digital sample value, (b) is larger than any other sample value in the buffer, and (c) differs from the first sample value in the buffer by more than a predetermined threshold value. The threshold is a fraction of the rise time slope of the last peak. The real time heart rate indication is calculated from the time duration separating the last two detected peaks, but rate indications outside the range of 30-200 beats per minute, and which depart from the preceding rate indication by more than 50 percent, are discarded.

Abstract: The invention relates to an arrangement for coding heart rate information, comprising means (600A, 600B) for measuring a person's heart beat intervals and means for storing (648) the measured heart beat interval information. The arrangement comprises means. (654) for coding the heart beat interval information stored in the storing means (648) into music, the coding means comprising means (660) for selecting the rhythm of the music on the basis of the measured heart beat intervals.

Abstract: The invention relates to a method and arrangement for measuring heart rate, including: means for inputting a heart rate limit for an exercise; means for measuring the user's heart rate .during the exercise. The arrangement further comprises means for changing the heart rate limit during the exercise on the basis of a predetermined change criterion associated with the exercise.

Abstract: A signal transmitting belt for transmitting a heartbeat signal to a heart rate monitor is provided, which shows a cardiorespiratory information. The signal transmitting belt includes: a main body comprising a signal transmitter for transmitting the heartbeat signal, an insulating chest belt, a connecting element connecting the main body and the insulating chest belt for sustaining a tension therebetween, and a conductive chest belt mounted on the insulating chest belt for contacting a chest of a user so as to detect the heartbeat signal and then transmit the heartbeat signal to the signal transmitter.

Abstract: A dual frequency transmitter, for use in remote monitoring of the heart rate of a living animal or human body, emits a first radio signal having a frequency of about 5 KHz and a second radio signal having a frequency substantially greater than 5 KHz. The dual frequency transmitter is preferably incorporated into personal property of the user, such as a wristwatch.

Abstract: An evaluation method that includes: recording the values of a physiological signal during a certain measuring period; dividing the obtained time series of signal values into individual segments; mapping successive subsets of the individual signal values in a segment on associated symbol series according to the criterion of whether a respective signal value increases or decreases as compared to the preceding signal value; determining the frequencies of the varying symbol series; determining a testing parameter which reflects the frequency ratio, within a segment, of correlated symbol series to anti-correlated symbol series; determining the relative difference of the testing parameters of two adjacent segments; and comparing the relative difference of two testing parameters with a given threshold as a criterion for the stationarity of the time series of the recorded physiological signal.

Abstract: The invention relates to a method for monitoring a condition of a patient under anaesthesia or sedation. In the method a signal (S) is acquired representing a cardiovascular activity of the patient, and periodically repeated waveforms (P) are detected, followed by calculation of time intervals (Ti) between, and/or pressures (Bi) from, and/or temporal rates (Ri) from successive waveforms. Next at least one of the following—a mathematical time series (T1, T2 . . . Tn, Tn+1 . . . ), or a mathematical pressure series (B1, B2 . . . Bn, Bn+1 . . . ), or a mathematical rate series (R1, R2 . . . Rn, Rn+1 . . . ) is/are formed. Further in the method said time series and/or said pressure series and/or said rate series is mathematically filtered to provide successive average values ({overscore (T)}i; {overscore (B)}i; {overscore (R)}i) over a predetermined first time period (&tgr;), and a substantial decrease, or increase respectively in said average values is detected.

Abstract: An arrangement for determining the heart rate (fRR) or the refractory time of the cardiac tissue, particularly for detecting tachycardia or fibrillation, has an electrode (E) for sensing heart action signals (SIG), an input stage, connected to the electrode, for processing the heart action signals, a refractory member for ascertaining a refractory time value of the arrangement, in each case after a predetermined segment of a heart action signal, and a processing device, connected to the output of the input stage or of the refractory member, for determining the rate of the heart action signals, processed with blanking of the component that occurs during the refractory time, or for determining the refractory time value of the cardiac tissue.

Abstract: A mobile client device, such as a wireless mobile or a palm sized personal digital assistant, is provided with a number of sensors and companion programming instructions/circuitry to generate a heart rate reading for a user holding the device. The sensors are used to sense blood flow rate of the user. The sensors are advantageously disposed in a distributed manner, in a number of locations of the mobile client device. The programming instructions/circuitry are used to infer a holding pattern of the device, and generate the heart rate reading, using a subset of the sensed data, based at least in part on the inferred holding pattern.