Abstract: The present invention provides a mobile ECG device by using accelerometer to improve real-time automatic analysis of heart rate variability, comprising: a data storage module; a microprocessor (MCU) module in which data are stored and accessed in the data storage module; an analog-to-digital converter module in which the data are transmitted to the microprocessor (MCU) module; an accelerometer peripheral hardware module in which the data are transmitted to the analog-to-digital converter module; and an electrocardiogram peripheral hardware module in which the data are transmitted to the analog-to-digital converter module.

Abstract: A physics-based mathematical model is used to estimate central pressure waveforms from measurements of a brachial pressure waveform measured using a supra-systolic cuff. The method has been tested in numerous subjects undergoing cardiac catheterisation. Central pressure agreement was within 11 mm Hg and as good as the published non-invasive blood pressure agreement between the oscillometric device in use and the so-called “gold standard.” It also exceeds international standards for the performance of non-invasive blood pressure measurement devices. The method has a number of advantages including simplicity of application, fast calculation and accuracy of prediction. Additionally, model parameters have physical meaning and can therefore be tuned to individual subjects. Accurate estimation of central waveforms also allow continuous measurement (with intermittent calibration) using other non-invasive sensing systems including photoplethysmography.

Abstract: Methods and systems described herein are especially useful wherein monitoring for atrial fibrillation (AF) is based on RR interval variability as measured from an electrocardiogram (ECG) signal. An activity threshold, which can be patient specific, is obtained. Patient activity is monitored. Based on the monitored patient activity and the activity threshold, there is a determination of when it is likely that AF monitoring based on RR interval variability is adversely affected by patient activity. When it has been determined that it is likely that AF monitoring based on RR interval variability is adversely affected by patient activity, whether and/or how AF monitoring is performed is modified.

Abstract: A method and system for extracting cardiac parameters from a plethysmographic signal is described wherein the plethysmographic signal is passed through a first filter to remove non-cardiac components of the signal. A second filter averages a plurality of cardiac cycles and cardiac parameters are extracted from the averaged cardiac signal.

Abstract: A method and apparatus to monitor and control the anesthesia state of a patient undergoing general anesthesia is provided. Previous automated systems to monitor the anesthesia state of a patient undergoing general anesthesia involve a significant time delay between the patient's true anesthesia state and the computed indices. The present invention reduces this time delay by using a novel analysis technique applied to spontaneous electrophysiological activity. A transformation and statistical analysis of the observed electrophysiological activity is conducted and compared to reference data to provide numerical indicators. In addition, these indicators are consistent with the levels of depression of patients CNS and ANS states. This method is illustrated in detail by CNS monitoring of electroencephalogram signals.

Abstract: A method of signal processing of data using a computer by generating a symbolic map of the data using at least one wavelet transform, identifying target sequences in the symbolic map; and processing the data with reference to the target sequences to obtain waveform prognostic indicators.

Abstract: A medical device and a method is suggested for assessing the risk of R on T events. The device comprises a memory, input means for acquiring or receiving an electrogram signal and processing means. The processing means are adapted to detect R-wave and T-waves represented by said electrogram, establish a QT-RR regression model based detected R-waves and T-waves, estimate a vulnerable period, and store estimated vulnerable period data in said memory. Likewise, the method comprises the steps of to detecting R-wave and T-waves represented by an electrogram, establishing a QT-RR regression model based detected R-waves and T-waves, estimating a vulnerable period, and storing estimated vulnerable period data.

Abstract: Disclosed are systems and methods for detecting the QRS portion of an electrocardiogram and also for detect QRS onset/offset points. QRS complexes are identified by testing selected waveform samples to determine if they are in a high curvature region. If a region passes the high curvature test, a verification test is applied to adjacent samples to confirm that the region is within a QRS complex. The search for a QRS onset point begins at an adaptive distance from this region. The curvature of selected regions ahead in the search direction is examined. The search moves past all such high curvature regions. The onset point is then located by searching for a region that is “flat” in either of two senses. First, a region may be locally flat (i.e. small first derivative) in an absolute sense. Second, a region is flat in a relative that further movement away from the interior of the QRS (e.g. toward “earlier” samples) does not result in a significant change in the value of the first derivative.

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: Disclosed is a system for detecting pathophysiological cardiac conditions. The system comprises a diagnostic device that contains electronic circuitry that can detect a cardiac event such as an acute ischemia. The cardiac diagnostic device receives electrical signals from subcutaneous or body surface sensors. The cardiac diagnostic device includes a processor that computes a measure of QRS curvature and applies an ischemia test based on the measure of QRS curvature to determine a likelihood of ischemia.

Abstract: Methods and systems are provided for performing ventricular arrhythmia monitoring using at least two sensing channels that are each associated with different sensing vectors, for example by different pairs of extracardiac remote sensing electrodes. Myopotential associated with each of the sensing channels in monitored, and a ventricular arrhythmia monitoring mode is selected based thereon (e.g., based on determined myopotential levels). Ventricular arrhythmia monitoring is then performed using the selected monitoring mode.

Abstract: Disclosed herein methods, devices, and systems for detecting and diagnosing a heart disease or disorder in a subject from a prime electrocardiogram which comprises calculating at least one distribution function of the prime electrocardiogram and determining whether the distribution function is indicative of the presence of absence of the heart disease or disorder.

Abstract: An method for analyzing irreversible apneic coma (IAC) for determining the presence of irreversible apneic coma (IAC) by analyzing the heart rate variability of a brain traumatic patient, thereby providing a physician a reference index to determine whether brain death has occurred. This method includes, at first, recording an electrocardiogram (ECG) from a subject. Then, analyzing R-R interval in said electrocardiogram (ECG), and plotting said R-R interval into Poincaré plot, wherein the X coordinate in said Poincaré plot represents R-R interval(n), and n is a 1˜data number. Y coordinate in said Poincaré plot represents RR(n+1). And, finally, quantifying said Poincaré plot, and obtaining semi-major axis (SD1), semi-minor axis (SD2), and SD1/SD2 of said Poincaré plot, as well as Poincaré plot area.

Abstract: Method and apparatus for sensing improvement using pressure data. The method and apparatus may be used in an implantable medical device to confirm that an EGM event signifies a true mechanical cardiac activity and not just electrical oversensing. The mechanical activity may be used to create a mechanical marker channel in the implantable medical device.

Abstract: Apparatus for monitoring an ECG signal comprises a first body wearable part 1 for receiving a physiological signal and comprising processing means, a memory, and a wireless transceiver, the memory storing a plurality of signal segment templates. The processing means is arranged to compare and match segments of the physiological signal to the stored template. The apparatus further comprises a second part 4 comprising a wireless transceiver and processing means, the processing means being arranged to generate and/or modify signal segment templates, and to cause said transceiver of the second part to transmit generated or modified templates to the first part.

Abstract: The present invention relates to a mobile diagnosis device comprised of an ECG unit (1) to record an ECG signal (55), with the ECG unit (1) being connected or connectible to two or more ECG electrodes (27, 28) to dissipate electrical signals from a patient's body, and comprised of a pulsoximetry unit (2) for simultaneous recording of a volume pulse signal (56), with the pulsoximetry unit (2) comprising at least one light source (17, 18) and at least one light sensor (20) for optical measurement of blood perfusion in the vascular system of a patient's body tissue, and comprised of a program-controlled evaluation unit (4) to evaluate the ECG signal (55) and the volume pulse signal (56).

Abstract: Electrocardiogram (ECG) recorded signals are processed by a computer-implemented method to substantially remove extraneous signals to produce intermediary signals, and to separate the intermediary signals using a non-orthogonal transformation method such as independent component analysis to produce independent components of signals. The separated signals are displayed to help physicians to analyze medical conditions and to identify locations of abnormal heart conditions.

Abstract: Systems and methods are provided for predicting the onset of postoperative atrial fibrillation (AF) from electrocardiogram (ECG) data representing a patient. A signal processing component determines parameters representing the activity of the heart of the patient from the ECG data. A feature extraction component calculates a plurality of features useful in predicting postoperative AF from the determined parameters. A classification component determines an AF index for the patient from the calculated plurality of features. The AF index represents the likelihood that the patient will experience AF.

Abstract: Methods and devices for establishing and using baseline for cardiac pacing response detection are described. A baseline amplitude of the cardiac signal may be established using data acquired in an evaluation interval prior to the delivery of the pacing pulse. An amplitude of the cardiac signal following delivery of the pacing pulse may be referenced using the baseline amplitude. An evoked response from the pacing pulse is detected using the referenced cardiac signal amplitude.

Abstract: A non-invasive diagnostic tool and method for detecting an obstruction in a coronary artery, the diagnostic tool including a signal processor adapted to receive signals corresponding to a heart beat from a plurality of acoustic sensors attached to the chest of a patient. The signal processor is programmed to identify a diastolic portion of the signals for a plurality of heartbeats and conduct a wavelet transform analysis on the diastolic signals for determining the existence of, as well as the severity and the location of, an obstruction in a coronary artery of the patient.

Abstract: This document describes systems, devices, and methods for detecting or validating cardiac beats, such as in the presence of myopotential or other noise. In one example, an amplitude peak, which is a candidate for a detected cardiac beat, is used in a weighted average, along with a preceding and subsequent sample. The weighted average is compared to a noise threshold. Based on the result of comparison, the amplitude peak is either deemed an actual cardiac beat, or otherwise is deemed noise. The described systems, devices, and methods improve the accuracy of detecting an actual cardiac beat in the presence of noise, during normal sinus rhythm or during an arrhythmia such as ventricular fibrillation. This, in turn, improves the accuracy with which therapy is delivered or withheld by an implantable cardiac rhythm management device. In one example, such as where the system includes a cardiac signal detector with automatic gain control (AGC) circuitry, the weighted average is normalized.

Abstract: Methods, devices, and software for selecting image slices. The image slices are preferably taken during a quiet part of the patient's heart cycle in which the heart is relatively motionless so as to reduce blurring and the introduction of artifacts into the resultant reconstructed projection image of the heart. The methods of the present invention can analyze information regarding the duration of the patient's R-R cycles and allow the user to choose from a plurality of selection criteria, typically an absolute time or a percentage of the R-R cycle, so as to select slice images for inclusion in a projection image. The ability to choose from a plurality of selection criteria provides for flexibility to account for irregular heartbeats or a change in the duration of the patient's R-R cycles. In exemplary embodiments, the resultant projection image can be used for coronary calcium scoring or 3-D rendering of the heart.

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 method of analysis of medical signals which uses wavelet transform analysis to decompose cardiac signals. Apparatus for carrying out the method, and cardiac apparatus adapted to employ the method are also described.

Abstract: A method and a system for detecting cardiac arrhythmias that includes detecting RR intervals of the patient wherein each RR interval is an interval between two heart beats, and simulating standard probability density histograms of ?RRs by means of a suitable probability distribution calculated through at least one mathematical formulae, wherein ?RR is a difference between two successive RR intervals. Test probability density histograms of ?RRs of the patient are constructed from the detected RR intervals. Finally, the standard and test histograms are compared to detect whether the patient suffers from cardiac arrhythmia. As non limiting examples, the standard probability density histograms of ?RRs are modeled by a mathematical equation selected from the group consisting of: the Lorentzian distribution, the Gaussian distribution, the Student's t-distribution, and a probability distribution including a linear combination of the Lorentzian and Gaussian distribution.

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: 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: There are many different serious cardiac arrhythmias. The present invention uses measurements of RR intervals (interbeat intervals) to detect, in particular but not exclusively, atrial fibrillation of a patient. Atrial fibrilation is a serious ailment in which the heartbeat is generally rapid and irregular. Probability density histograms of ?RRs (difference between two successive RR intervals) collected during atrial fibrillation of a plurality of subjects are used as a template for the detection of atrial fibrillation. In one implementation, there are 16 standard probability density ?RRs histograms every 50 ms of mean RR interval of a certain number of beats, where the mean RR interval ranges from 350 ms to 1149 ms. Similarity between the standard probability density histograms and a test density probability histogram of ?RRs of a patient is estimated by the Kolmogorov-Smirnov test.

Abstract: A method and an apparatus for selecting an antenna from an antenna diversity array in a wireless communication system are provided. The method includes the steps of modulating an incoming signal with a spread-spectrum type modulation, measuring a signal quality value for each antenna in the antenna diversity array, and selecting an antenna from the antenna diversity array on the basis of the measured signal quality values. The step of measuring a signal quality value for each antenna may include computing peak-to-average ratio values by dividing a peak sample value by an average sample value, where the average sample value is determined by averaging all of the predetermined number of sample values for each of the plurality of incoming spreading codewords, and the peak sample value is determined by selecting the maximum of all of the predetermined number of sample values for each of the plurality of incoming spreading codewords.

Abstract: An implantable cardiac device and method provides for monitoring a progression or regression in heart disease during an extended time period. A sensor generates an electrogram signal representing electrical activity of a patient's heart. From the generated electrogram signal, a processor determines morphology measurements wherein the morphology measurements indicate a progression or regression in the heart disease. The morphology measurements are stored in a memory during the extended period of time. A telemetry circuit transmits the stored morphology measurements to an external receiver for retrieval or display. The morphology measurements may be of electrogram intrinsic activity or evoked response activity characteristics.

Abstract: The present invention uses a R-wave sensing algorithm that uniquely combines an automatic threshold adjustment method with a new noise rejection technique. This algorithm has significant advantages in avoiding the sensing of T-waves, P-waves, and noise/artifacts. Detecting the presence of noise bursts uses features that determine if an R-R interval adjacent to or within the noise signal is valid. Circuitry that discriminates noise signals from R-waves can use any one of several features including, but not limited to, the following: detection events occurring so close together that they are outside normal physiologic heart rates; frequency content that is wider than that of QRS complexes; amplitudes that are different than the adjacent or encompassing R-waves; and amplitudes that display greater than normal variability.

Abstract: Computer implemented methods and associated systems are disclosed for processing electrical signals recorded from the heart and, more particularly, for objectively deriving sub-components and comparing signals and their sub-components.

Abstract: A method for monitoring the progression of the hemodynamic status of a patient by tracking autonomic tone. For example, the method may be applied to patients suffering from heart failure, diabetic neuropathy, cardiac ischemia, sleep apnea and hypertension. An implantable or other ambulatory monitor senses a pulse amplitude signal such as a vascular plethysmography signal. Variations of the signal amplitude on a scale greater than the heartbeat to heartbeat scale are indicative of variations in autonomic tone. A significant reduction in pulse amplitude and pulse amplitude variability are indicative of a heart failure exacerbation or other disease state change. This information may be used to warn the patient or healthcare providers of changes in the patient's condition warranting attention.

Abstract: Methods for conducting an electrophysiology procedure using a programmed machine are described, including methods for managing discrete data capture requests received throughout the course of an electrophysiology procedure and for discretizing the display of independent data capture events that occur during the course of the electrophysiology procedure. These methods enable an operator to review location maps of sites visited during the course of a procedure and to review data from discrete moments in the procedure and to play back data over a sequence of times throughout the procedure, one moment at a time. The invention further includes software constructs that enable data management.

Abstract: A signal evaluation method for detecting QRS complexes in electrocardiogram (ECG) signals comprises the following steps: sampling of the ECG signal (4) and conversion into discrete signal values (x(n)) in chronological order; comparing the signal values (xf(n), xfq(n)) to a threshold function (K(n)) adaptively determined therefrom; determining a frequency number (D(n)) within a defined segment of the consecutive signal values, by which signal values (xf(n), xfq(n)) preferably fall short of the threshold function (K(n)); comparing the determined frequency number (D(n)) to a defined threshold (?), wherein an undershoot of the threshold (?) is significant for apresence of a QRS complex (5, 6, 7) in the defined segment of the ECG signal (4).

Abstract: An apparatus and method for detecting an atrial fibrillation through monitoring the R—R intervals of a patient's QRS complexes. Ratios of the current R—R interval are made to previous R—R intervals. Multiple moving averages are taken of the ratio results. The ratios are compared to a validating threshold and if the particular ratio is within a selected range, a moving average is calculated with inclusion of the present R—R interval. If the ratio is outside the range, a moving average is calculated without inclusion of the current R—R interval. The moving averages are combined and this difference average is compared to a trigger threshold. If the difference average exceeds the threshold, an atrial fibrillation is determined to exist, a memory trigger is provided, and the QRS complex data within a selected period of time about the atrial fibrillation event are recorded and removed from overwrite status in the memory.

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: A method and system for extracting cardiac parameters from a plethysmographic signal is described wherein the plethysmographic signal is passed through a first filter to remove non-cardiac components of the signal. A second filter averages a plurality of cardiac cycles and cardiac parameters are extracted from the averaged cardiac signal.

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: Techniques for monitoring the magnitudes of representative filtered EGM signals over time. In a typical implementation, a group of digital peak values is generated in a time period and a representative digital peak value is selected for the time period. By comparing representative peak values for several time periods, changes in signal efficacy can be identified.

Abstract: The present invention uses a R-wave sensing algorithm that uniquely combines an automatic threshold adjustment method with a new noise rejection technique. This algorithm has significant advantages in avoiding the sensing of T-waves, P-waves, and noise/artifacts. Detecting the presence of noise bursts uses features that determine if an R-R interval adjacent to or within the noise signal is valid. Circuitry that discriminates noise signals from R-waves can use any one of several features including, but not limited to, the following: detection events occurring so close together that they are outside normal physiologic heart rates; frequency content that is wider than that of QRS complexes; amplitudes that are different than the adjacent or encompassing R-waves; and amplitudes that display greater than normal variability.

Abstract: The invention provides new materials and devices for EKG gating and defibrillation that alleviate problems in the art. Embodiments of the invention utilize special electrodes of certain dimensions and made from materials that can generate trigger signals or transmit pulses more reliably and/or with less interference to other diagnostic procedures. The electrodes and systems improve the amplitude and overall reliability of detecting EKG signals. The improved signals enable more reliable detection of a true cardiac phase and improved cardiac gating. Thus, embodiments of the invention lead to improved image quality, more accurate imaging of cardiac and intrathoracic/upper abdominal structures and improved referencing of systemic arterial blood flow for blood flow measurement within the chest and elsewhere in the body, including, for example, the extremities.

Abstract: An electrocardiogram (ECG) system provides a set of ECG lead signals. The system includes a source of a subset of ECG lead signals. A synthesizer, coupled to the ECG lead signal source, generates a set of synthesized ECG lead signals from the subset of ECG lead signals. Data is also generated representing the accuracy of the set of synthesized ECG lead signals.

Abstract: A signal evaluation method for detecting QRS complexes in electrocardiogram signals incorporates the following process steps: sampling of the signal (4) and conversion to discrete signal values (x(n)) in chronological order, determining the sign of each signal value (x(n)), continuous checking of the signs of consecutive signal values (x(n)) for the presence of a zero crossing between two consecutive signal values (x(n)), determining the number (D(n)) of zero crossings in a defined segment (N) of the consecutive signal values (x(n)), and comparing the determined number of zero crossings (D(n)) to a defined threshold value, wherein an undershoot of the threshold value signifying the presence of a QRS complex (5, 6, 7) in the defined segment of the signal curve (4).

Abstract: A vital signal detecting apparatus comprises an attachable device to be attached to a finger, a sensor having a light-emitting device and a light-receiving device, and a transmitting circuit for transmitting a signal waveform as a pulse wave from the sensor to a pulse wave monitoring unit. The pulse wave detecting unit also has an attachment detecting circuit for detecting whether or not the attachable device is in an attached state by comparing a signal waveform obtained when the light-emitting device is on with a signal waveform obtained when the light-emitting device is off and an operation control circuit for controlling the operation of the sensor, the transmitting circuit and the attachment detecting circuit. Preferably, the light-transmitting plate is disposed above the light-emitting device and the light-receiving device to pass light therethrough, and the light transmitting plate may be an IR-cut filter capable of blocking light of wavelengths greater than 700 nm.

Abstract: An apparatus for processing physiological signals, which includes a signal pick-up unit for picking up physiological measurement signals, in particular for picking up electrical signals of a heart, and first detection means which are connected to the signal pick-up unit and include signal processing means such as a filter and a first threshold value store and a comparison unit which is connected thereto and which is adapted to output a first marker signal if the amplitude of the measurement signal exceeds a threshold value stored in the first threshold value store, second detection means which are connected to the signal pick-up unit and include a second threshold value store and a second comparison unit which is connected thereto and which is adapted to output a second marker signal if the amplitude of the measurement signal exceeds a threshold value stored in the second threshold value store, and an evaluation unit which is connected to the first and second detection means for taking over a respective serie

Abstract: An arrangement for detecting a heart beat and calculating heart rate on the basis of the detected heart beats, comprising means for measuring an EKG signal from a person's hands, a computer for detecting a heart beat from the measured signal and for performing a rationality analysis to verify a heart beat detection and for calculating the heart rate on the basis of the detected heart beats, the arrangement further comprising means for displaying the calculated heart rate and connected to the computer.

Abstract: In one aspect of the invention, there is provided a method and apparatus for early detection of subacute, potentially catastrophic infectious illness in a premature newborn infant. The method comprises: (a) continuously monitoring heart rate variability in the premature newborn infant; and (b) identifying at least one characteristic abnormality in the heart rate variability that is associated with the illness. This method can be use to diagnose illnesses such as, but not limited to, sepsis, necrotizing enterocolitis, pneumonia and meningitis. In another aspect of the present invention, there is provided a method and apparatus for early detection of subacute, potentially catastrophic infectious illness in a patient.

Abstract: Based upon patient studies indices a high degree of correlation was found between HRV and VO2max, i.e., the patient's exercise capacity. Based on this finding, a pacing therapy optimization protocol for treating patients with CHF has been devised. The protocol involves first pacing the patient's heart with a pacemaker programmed to operate in a first mode for a predetermined time period and then collecting electrogram data from which a HRV index is derived. The mode is then changed and the steps repeated until all possible modes have been utilized. At that time, a determination is made as to which of the modes is associated with the largest HRV index and the pacemaker is then programmed to function in that mode. Alternatively, the method of the present invention can be applied to changes in drug therapy instead of or in combination with pacing therapy. By the plotting the HRV index computed in the manner described, the efficacy of a change in therapy on patient exercise capacity can be assessed.

Abstract: A method and system for identifying components of a waveform. The system includes an ECG acquisition module, a pressure waveform acquisition module to acquire a pressure waveform, and an analysis module coupled to the ECG acquisition module and the pressure waveform acquisition module. A monitor or similar display device is coupled to the analysis module. The analysis module is operable to determine three peaks in the pressure waveform corresponding to “a”, “c”, and “v” waves. Those “a”, “c”, or “v” waves that are identified by the analysis module are displayed on a monitor or similar device such that they are distinguished from each other and the remainder of the displayed waveform. The method involves displaying a waveform; identifying a number of peaks in a number of intervals of the waveform, and modifying the displayed waveform such that the identified peaks are distinguished from each other and the rest of the pressure waveform.