Variation In Duration Of Segment Of Pqrst Signal Waveform (e.g., Qrs Complex, Etc.) Detected Patents (Class 600/516)
  • Patent number: 7725172
    Abstract: A method and system for detecting T-wave alternans for use in an implanted medical device uses wave transformation of QT intervals to obtain a reliable measure of TWA. In one embodiment, an array provides alternating sign multiplication factors which are applied respectively to n consecutive QT values. Each successive QT value is high pass filtered and moved sequentially through a queue so that each cycle each of the n QT values is multiplied by one of the factors; the products are summed and made absolute to provide an alternans match value. The alternans match is compared with a noise threshold signal, and alternans is declared when the match exceeds the threshold by a predetermined amount. The array is programmable and can be varied, providing a high degree of flexibility to optimize the test for the patient.
    Type: Grant
    Filed: January 12, 2004
    Date of Patent: May 25, 2010
    Assignee: Medtronic, Inc.
    Inventors: Mattias Rouw, Christianus J. J. E. Van Groeningen, Henricus Willem M. De Bruyn
  • Publication number: 20100125184
    Abstract: A chip for sensing a physiological signal comprises: an input unit for receiving a first electrocardiogram (ECG) signal; a filter for generating a second ECG signal by filtering the first ECG signal; an amplifying unit for generating a third ECG signal by amplifying the second ECG signal; an Analog-to-Digital converting unit for converting the third ECG signal into a digital signal; an operating unit for generating a plurality of analysis data by operational analyzing the digital signal; and an output unit for outputting the plurality of analysis data. Therefore, the manufacturing cost of the chip is decreased and the chip is suitable for use in small-scale devices.
    Type: Application
    Filed: March 20, 2009
    Publication date: May 20, 2010
    Applicant: National Yang Ming University
    Inventors: Bo-Jau Kuo, Ching-Hsiu Yang
  • Patent number: 7720536
    Abstract: A power supply for an implantable cardioverter-defibrillator for subcutaneous positioning between the third rib and the twelfth rib and for providing cardioversion/defibrillation energy to the heart, the power supply comprising a capacitor subsystem for storing the cardioversion/defibrillation energy for delivery to the patient's heart; and a battery subsystem electrically coupled to the capacitor subsystem for providing electrical energy to the capacitor subsystem.
    Type: Grant
    Filed: June 6, 2006
    Date of Patent: May 18, 2010
    Assignee: Cameron Health, Inc.
    Inventors: William J. Rissmann, Gust H. Bardy, Riccardo Cappato
  • Patent number: 7715909
    Abstract: A seismocardiograph using multiple accelerometer sensors to identify cardiac valve opening and closing times. A methodology for selecting event times is also disclosed.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: May 11, 2010
    Assignee: Acceleron Medical Systems, Inc.
    Inventors: John M. Zanetti, Douglas Perlick
  • Publication number: 20100106035
    Abstract: A method of classifying arrhythmias using scatter plot analysis to define a measure of variability of a cardiac rhythm parameter such as for example, without limitation, R-R interval, A-A interval, and the slope of a portion of a cardiac signal, is disclosed. The variability measurement is derived from a scatter plot of a cardiac rhythm parameter, employing a region counting technique that quantifies the variability of the cardiac rhythm parameter while minimizing the computational complexity. The method may be employed by an implantable medical device or system, such as an implantable pacemaker or cardioverter defibrillator, or by an external device or system, such as a programmer or computer. The variability measurement may be correlated with other device or system information to differentiate between atrial flutter and atrial fibrillation, for example. The variability information may also be used by the device or system to select an appropriate therapy for a patient.
    Type: Application
    Filed: December 31, 2009
    Publication date: April 29, 2010
    Applicant: Medtronic, Inc.
    Inventors: Peter M. Van Dam, Joanneke G. Groen
  • Patent number: 7702383
    Abstract: Systems and related methods for analyzing data sensed from a device implanted in a patient, such as a cardiac pacing system. The system detects and evaluates electric signals within the patient that share a common event marker. By using algorithms and graphical presentation of the collected signals having common event markers, deviations in signals over time can be identified and evaluated in consideration of taking further action related to the patient and the implanted device. The system can also be used in conjunction with an advanced patient management system that includes a programmer or repeater capable of gathering information from the implanted device and transmitting the data to a host via a communications network for evaluation at a remote location.
    Type: Grant
    Filed: May 4, 2006
    Date of Patent: April 20, 2010
    Assignee: Cardiac Pacemakers, Inc.
    Inventors: Matthias Woellenstein, Howard Simms, Scott Mazar, Robert Sweeney
  • Publication number: 20100010359
    Abstract: The present invention comprises methods and apparatus for detecting prolonged myocardial repolarization as an indicator of cardiac conditions, including without limitation, transmural ischemia. In some embodiments, without limitation, the present invention comprises methods and apparatus to detect prolonged repolarization using electrocardiographic and electrophysiological tools and measurements.
    Type: Application
    Filed: March 9, 2009
    Publication date: January 14, 2010
    Inventors: DAVID N. KENIGSBERG, Sanjaya Khanal, Marcin Kowalski, Subramaniam Krishnan
  • Publication number: 20090326401
    Abstract: Electrocardiogram data is received in association with a subject, the electrocardiogram data comprising a series of RR intervals and a series of QT intervals. A first value which indicates an amount by which uncertainty associated with the QT intervals is reduced given the RR intervals is generated. A second value which indicates an amount by which uncertainty associated with the RR intervals is reduced given the QT intervals is generated. The subject is determined to be associated with a low risk of cardiac dysfunction responsive to the first value exceeding the second value and a result of the determination is provided.
    Type: Application
    Filed: January 26, 2009
    Publication date: December 31, 2009
    Applicant: UNIVERSITY OF SOUTHERN CALIFORNIA
    Inventors: Edmond Jonckheere, Fariba Ariaei, Timothy Callahan, William Stuppy
  • Patent number: 7630521
    Abstract: A biometric identification apparatus and method using bio signals and an artificial neural network, are provided. The biometric identification apparatus includes: a periodic signal extraction unit which extracts one or more periodic signals from an input bio signal; a template calculation unit which calculates a template value using the extracted periodic signals; a template storage unit which stores a plurality of template values corresponding to a plurality of living bodies; and a reading unit which reads the template value that is most approximate to the template value calculated by the template calculation unit from the template storage unit. Accordingly, it is possible to identify a living body by taking into consideration all of the characteristics of bio signals detected from the living body.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: December 8, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Kyung-ho Kim, Kyeong-seop Kim, Tae-ho Yoon
  • Patent number: 7627369
    Abstract: A method and apparatus for measuring the QT interval of an electrocardiogram (ECG) signal is provided wherein the end of the T wave is identified from ECG data. The end of the T wave is defined as the first time of intersection at which an upright T wave of a first set of derived ECG signal data intersects an inverted T wave of a second set of derived ECG signal data. The intersection of the two sets of ECG data is along an isoelectric line within the trough after the positive T wave peak when the superimposed isoelectric baselines from the upright and inverted ECG signals demonstrate the best least squares fit.
    Type: Grant
    Filed: October 10, 2003
    Date of Patent: December 1, 2009
    Assignee: PSI Heartsignals (Global) Limited
    Inventor: Anthony Charles Hunt
  • Patent number: 7627368
    Abstract: A medical device performs a method for detecting atrial arrhythmias. A signal including ventricular cycle length information is sensed in a patient and used to determine each difference between successive ventricular cycle lengths occurring during a predetermined time period. Each succeeding difference is stored as a data point in a histogram, and a metric of variability of the data points of the histogram is determined. An atrial arrhythmia is detected in response to the metric crossing a threshold. The threshold is determined in response to the number of ventricular cycle lengths occurring during the predetermined time period.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: December 1, 2009
    Assignee: Medtronic, Inc.
    Inventors: Richard P.M. Houben, Vincent Larik, Tim D.J. Jongen
  • Patent number: 7623910
    Abstract: A method differentiating LQT1 mutation from LQT2 mutation is disclosed. An ECG signal is obtained for a patient. At least a first ECG parameter and a second ECG parameter are determined from the ECG signal. A probability that the patient is an LQT1 carrier or an LQT2 carrier is determined based on a regression model which takes into account the first ECG parameter and the second ECG parameter. A system for assessing repolarization abnormalities is also disclosed. The system has a processor configured to differentiate between LQT1 and LQT2 based on at least two ECG parameters from ECG data. The system also has a data input coupled to the processor and configured to provide the processor with the ECG data. The system further has a user interface coupled to either the processor or the data input.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: November 24, 2009
    Assignee: University of Rochester
    Inventors: Jean-Philippe Couderc, Martino Vaglio
  • Patent number: 7623909
    Abstract: Methods and devices for sensing vector analysis in an implantable cardiac stimulus system. In an illustrative example, a first sensing vector is analyzed to determine whether it is suitable, within given threshold conditions, for use in cardiac event detection and analysis. If so, the first vector may be selected for detection and analysis. Otherwise, one or more additional vectors are analyzed. A detailed example illustrates methods for analyzing sensing vectors by the use of a scoring system. Devices adapted to perform these methods are also discussed, including implantable medical devices adapted to perform these methods, and systems comprising implantable medical devices and programmers adapted to communicate with implantable medical devices, the systems also being adapted to perform these methods. Another example includes a programmer configured to perform these methods including certain steps of directing operation of an associated implanted or implantable medical device.
    Type: Grant
    Filed: May 26, 2006
    Date of Patent: November 24, 2009
    Assignee: Cameron Health, Inc.
    Inventors: Rick Sanghera, Venugopal Allavatam
  • Publication number: 20090281441
    Abstract: A system for heart performance characterization and abnormality detection includes an acquisition device for acquiring an electrophysiological signal representing heart beat cycles of a patient heart. A detector detects one or more parameters of the electrophysiological signal of parameter type comprising at least one of, (a) amplitude, (b) time duration, (c) peak frequency and (d) frequency bandwidth, of multiple different portions of a single heart beat cycle of the heart beat cycles selected in response to first predetermined data. The multiple different portions of the single heart beat cycle being selected from, a P wave portion, a QRS complex portion, an ST segment portion and a T wave portion in response to second predetermined data. A signal analyzer calculates a ratio of detected parameters of a single parameter type of the multiple different portions of the single heart beat cycle.
    Type: Application
    Filed: April 3, 2009
    Publication date: November 12, 2009
    Applicant: Siemens Medical Solutions USA, Inc.
    Inventors: Hongxuan Zhang, Detlef W. Koertge, Dennis Steibel, JR.
  • Patent number: 7593764
    Abstract: The present disclosure includes a system and method of detecting LQTS in a patient by comparing a collected set of ECG data from the patient to a plurality of databases of collected ECG data. The plurality of databases will include a database containing previous ECGs from the patient, a known acquired LQTS characteristics database, and a known genetic LQTS characteristics database. Comparing the patients ECG to these databases will facilitate the detection of such occurrences as changes in QT interval from success of ECGs, changes in T-wave morphology, changes in U-wave morphology and can match known genetic patterns of LQTS. The system and method is sensitive to patient gender and ethnicity, as these factors have been shown to effect LQTS, and is furthermore capable of matching a QT duration to a database of drug effects. The system and method is also easily integrated into current ECG management systems and storage devices.
    Type: Grant
    Filed: October 3, 2006
    Date of Patent: September 22, 2009
    Assignee: General Electric Company
    Inventors: Mark Kohls, Ian Rowlandson, Joel Xue
  • Publication number: 20090234211
    Abstract: Embodiments of the invention are related to devices and methods for myocardial ischemia detection, amongst other things. In an embodiment, the invention includes an implantable medical device including control circuitry, an electrical field sensor in communication with the control circuitry, the electrical field sensor configured to generate a signal corresponding to cardiac electrical fields. The implantable medical device can also include a chemical sensor in communication with the control circuitry, the chemical sensor configured to generate a signal corresponding to the concentration of a physiological analyte that affects cardiac electrical field waveform morphology. The control circuitry can be configured to monitor for the presence of myocardial ischemia by evaluating both the signal generated by the electrical field sensor and the signal generated by the chemical sensor. Other embodiments are also included herein.
    Type: Application
    Filed: March 11, 2009
    Publication date: September 17, 2009
    Applicant: CARDIAC PACEMAKERS, INC.
    Inventors: Dan Li, Haresh G. Sachanandani, Michael John Kane, Yi Zhang
  • Publication number: 20090234239
    Abstract: Apparatus for graphical representation of a train of ECG complexes, said ECG complexes comprising an R wave and a T-P interval and having variable isoelectric levels, the apparatus comprising: an isoelectric alignment unit for aligning the complexes in terms of isoelectric level by aligning respective T-P intervals, thereby to provide a graphical representation of said train of ECG complexes; and a temporal alignment unit for aligning said complexes temporally using a predetermined point of respective R waves. The aligned units are superimposed to provide a distribution of a normalized ECG signal over a series of pulses or heartbeats.
    Type: Application
    Filed: May 16, 2006
    Publication date: September 17, 2009
    Inventors: Benjamin Shani, Shai Revzen, Aaron Frimerman
  • Patent number: 7580740
    Abstract: Methods and systems are directed to detecting atrial tachyarrhythmia. A plurality of A-A intervals is detected. The detected A-A intervals are selected and used to detect atrial tachyarrhythmia. Selecting A-A intervals may be based on determining that A-A intervals are qualified. Qualified A-A intervals may be determined if a duration of the particular A-A interval falls outside a predetermined duration range, for example. Qualified A-A intervals may also be determined based on events occurring between consecutively sensed atrial events of the particular A-A interval, and whether the duration of the particular A-A interval falls within the predetermined duration range, for example.
    Type: Grant
    Filed: May 11, 2005
    Date of Patent: August 25, 2009
    Assignee: Cardiac Pacemakers, Inc.
    Inventors: Jaeho Kim, Joseph M. Bocek, Anthony S. Harrington, Harley G. White
  • Publication number: 20090192397
    Abstract: Disclosed is a “tracker system” that includes implanted electrical leads which are part of an implanted cardiotracker plus external equipment that includes external alarm means 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 means 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.
    Type: Application
    Filed: February 26, 2009
    Publication date: July 30, 2009
    Inventors: David R. Fischell, Robert E. Fischell, Jonathan Harwood, Steven R. Johnson
  • Patent number: 7567836
    Abstract: A system comprising a processor that includes a cardiac signal vector module and an ischemia detection module. The cardiac signal vector module is configured to measure a first dominant vector corresponding to a direction and magnitude of maximum signal power of a first segment of at least one cardiac cycle of a subject and at least a second dominant vector corresponding to a direction and magnitude of maximum signal power of a second segment of the cardiac cycle from an electrical cardiac signal. The ischemia detection module is configured to measure a change in the first dominant vector, to form a difference by subtracting a measured change in the second dominant vector from a measured change in the first dominant vector, and to declare whether an ischemic event occurred using the difference.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: July 28, 2009
    Assignee: Cardiac Pacemakers, Inc.
    Inventor: Yi Zhang
  • Publication number: 20090177103
    Abstract: Techniques are described for detecting and distinguishing among ischemia, hypoglycemia or hyperglycemia based on intracardiac electrogram (IEGM) signals. In one technique, these conditions are detected and distinguished based on an analysis of: the interval between the QRS complex and the peak of a T-wave (QTmax), the interval between the QRS complex and the end of a T-wave (QTend), alone or in combination with a change in ST segment elevation. By exploiting QTmax and QTend in combination with ST segment elevation, changes in ST segment elevation caused by hypo/hyperglycemia can be properly distinguished from changes caused by cardiac ischemia. In another technique, hyperglycemia and hypoglycemia are predicted, detected and/or distinguished from one another based on an analysis of the amplitudes of P-waves, QRS-complexes and T-waves within the IEGM. Appropriate warning signals are delivered and therapy is automatically adjusted.
    Type: Application
    Filed: March 18, 2009
    Publication date: July 9, 2009
    Applicant: PACESETTER, INC.
    Inventor: Rupinder Bharmi
  • Publication number: 20090177102
    Abstract: A system and method for predicting sudden cardiac death. The system includes a patient monitoring station, a Holter analysis workstation, and a hospital information network. The Holter analysis workstation being operative to apply a plurality of data analysis algorithms to create a sudden cardiac death report. The method applies a first data analysis technique and a second data analysis technique to electrocardiographic data to produce an indication of sudden cardiac death risk.
    Type: Application
    Filed: January 7, 2008
    Publication date: July 9, 2009
    Applicant: The General Electric Company
    Inventors: Mary Schneider, Patrick Dorsey, Joel Schoenbeck
  • Publication number: 20090171227
    Abstract: A system and method providing outpatient ECG monitoring and safe home based cardiac tele-rehabilitation. The system includes a recordation module for recording ECG signals using at least one lead, a tele-rehabilitation module for home based exercise management for a patient's recovery from a heart disease, the tele-rehabilitation module including a processing module for recognizing erroneous data from the ECG signals and an analysis module for calculating beat-to-beat annotations and determining if an ECG event and/or if a QT interval duration change has occurred.
    Type: Application
    Filed: October 16, 2006
    Publication date: July 2, 2009
    Inventors: Marek Dziubinski, Ryszard Piotrowicz, Ewa Piotrowicz, Rafal Baranowski
  • Patent number: 7546160
    Abstract: A device and method is disclosed for improving tachyarrhythmia detection when the ventricles are resynchronized by delivering paces to both ventricles separated by a specified negative offset interval. Timing of escape intervals and tachyarrhythmia detection is based upon senses from one of the ventricles designated as a rate ventricle. Techniques are presented for preventing tachyarrhythmia detection from being compromised when the rate ventricle is paced after the other ventricle.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: June 9, 2009
    Assignee: Cardiac Pacemakers, Inc.
    Inventors: Jeffrey E. Stahmann, Andrew P. Kramer, Julio C. Spinelli
  • Publication number: 20090143692
    Abstract: In a method for determining a cardiac condition, a sensed physiologic signal for a period of time including multiple cardiac cycles is received. Using the received physiologic data, a heart beat frequency to be used as a reference frequency is determined. A plurality of harmonics of the received physiologic signal is extracted based on the reference frequency, wherein the harmonics correspond to a plurality of alternans frequencies. Amplitudes of at least some of the extracted harmonics are determined, and are used to determine an alternans indicator value.
    Type: Application
    Filed: November 26, 2008
    Publication date: June 4, 2009
    Applicant: Transoma Medical, Inc.
    Inventors: Marina V. Brockway, Vladimir V. Kovtun, Carlos A. Ricci
  • Publication number: 20090137916
    Abstract: Electrocardiologic device for assisted diagnosis, preferably for the diagnosis of Brugada syndrome or Early Repolarization syndrome. This device allows characterizing the ventricular repolarization wave of an ECG signal collected from a patient. Extracting out of the ECG signal, for each heart beat, an ST segment is constituted of a successsion of samples of the ventricular repolarization wave, taken within a time window ([QON+80 ms, QON+140 ms]) of a predetermined duration spreading from a moment of window onset defined by a time offset applied to a predetermined temporal origin given by the moment (QON) of appearance of the QRS complex, whose time position is determined on the ECG signal for each heart beat. Quantizing computes an elevation index compared to a predetermined reference level (BL), and analyzing over a succession of heart beats the persistence and/or variation of this elevation index.
    Type: Application
    Filed: October 21, 2008
    Publication date: May 28, 2009
    Inventors: Pierre Maison-Blanche, Fabrice Extramiana
  • Publication number: 20090105602
    Abstract: A two-stage digital algorithm uses a highly sensitive low power digital first stage to detect one or more alarm conditions, and one or more complex digital subsequent stages that identify the detected alarm condition with more specificity. The one or more complex digital subsequent stages are not activated, and consume no power, until an alarm condition is sensed by the low power consumption digital first stage. Given that the second stage will process the data more rigorously, the low power first stage can be set to be more sensitive and generate what would otherwise be excessive alarms, which are ultimately filtered out by the subsequent stages. By staging the digital analysis algorithms, the present invention achieves high sensitivity for alarm conditions with low computational throughput and low power consumption, and achieves high specificity with more computationally intensive algorithms that only run occasionally.
    Type: Application
    Filed: February 11, 2005
    Publication date: April 23, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventors: Stacy Gehman, Thomas Lyster
  • Patent number: 7515956
    Abstract: An implantable cardioverter/defibrillator includes a tachycardia detection system that detects one-to-one (1:1) tachycardia, which is a tachycardia with a one-to-one relationship between atrial and ventricular contractions. When the 1:1 tachycardia is detected, the system discriminates ventricular tachycardia (VT) from supraventricular tachycardia (SVT) based on analysis of a cardiac time interval. Examples of the cardiac time interval include an atrioventricular interval (AVI) and a ventriculoatrial interval (VAI). A template time interval is created during a known normal sinus rhythm. The system measures a tachycardia time interval after detecting the 1:1 tachycardia, and indicates a VT detection if the tachycardia time interval differs from the template time interval by at least a predetermined percentage of the template time interval.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: April 7, 2009
    Assignee: Cardiac Pacemakers, Inc.
    Inventor: Julie Thompson
  • Publication number: 20090076403
    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 QRS onset and offset points and fiducial points associated with T and U waves. The processor than baseline corrects the original signal/waveform by fitting a polynomial function to QRS offset points, and subtracting this function from the original waveform.
    Type: Application
    Filed: September 14, 2007
    Publication date: March 19, 2009
    Inventor: Bruce Hopenfeld
  • Patent number: 7502644
    Abstract: Techniques are described for detecting ischemia, hypoglycemia or hyperglycemia based on intracardiac electrogram (IEGM) signals. Ischemia is detected based on a shortening of the interval between the QRS complex and the end of a T-wave (QTmax), alone or in combination with a change in ST segment elevation. Alternatively, ischemia is detected based on a change in ST segment elevation combined with minimal change in the interval between the QRS complex and the end of the T-wave (QTend). Hypoglycemia is detected based on a change in ST segment elevation along with a lengthening of either QTmax or QTend. Hyperglycemia is detected based on a change in ST segment elevation along with minimal change in QTmax and in QTend. By exploiting QTmax and QTend in combination with ST segment elevation, changes in ST segment elevation caused by hypo/hyperglycemia can be properly distinguished from changes caused by ischemia.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: March 10, 2009
    Assignee: Pacesetter, Inc.
    Inventors: Jong Gill, Peter Boileau, Rupinder Bharmi, Xiaoyi Min, Joseph J. Florio, Michael Benser, Gene A. Bornzin
  • Publication number: 20090048528
    Abstract: Disclosed is a system for detecting pathophysiological cardiac conditions from a reduced number of extracardiac leads. A right side lead measures the electrical signal between the middle superior chest region over the heart and inferior right torso position. A left side lead measures the electrical signal between the left precordial chest region and an inferior left lateral or posterior torso position. The lead montage is preferably chosen so that, regardless of patient position (e.g. supine, upright), negative ST segments and/or T waves are used to detect right coronary or left circumflex ischemia. Also, in these positions, reduced slope of the final deflection in the QRS can be used to detect these types of ischemia. To detect transmural ischemia, the system examines changes in QRS slopes, ST segment, T wave and the difference between the J point and the PQ potentials.
    Type: Application
    Filed: August 16, 2007
    Publication date: February 19, 2009
    Inventors: Bruce Hopenfeld, Michael Sasha John, Tim Fischell
  • Publication number: 20090043218
    Abstract: A method employable during a tachycardia-tachyarrhythmia condition in a person for detecting, verifying and distinguishing ventricular and supra-ventricular tachyarrhythmias, including ventricular fibrillation, including (a) confirming the presence of a tachyarrhythmia heart rate, (b) on such confirmation, collecting time-frame-simultaneous ECG and heart-sound information, (c) following such collecting, choosing selected ECG time-span, and heart-sound intensity, data, and (d) utilizing the chosen, selected ECG time-span, and heart-sound intensity, data, characterizing the defined condition as resulting from one of (a) supra-ventricular tachyarrhythmia, (b) ventricular tachyarrhythmia, and (c) ventricular fibrillation.
    Type: Application
    Filed: August 6, 2008
    Publication date: February 12, 2009
    Inventors: Robert A. Warner, Patricia A. Arand, Peter T. Bauer
  • Patent number: 7483741
    Abstract: A device and method is disclosed for improving tachyarrhythmia detection when the ventricles are resynchronized by delivering paces to both ventricles separated by a specified negative offset interval. Timing of escape intervals and tachyarrhythmia detection is based upon senses from one of the ventricles designated as a rate ventricle. Techniques are presented for preventing tachyarrhythmia detection from being compromised when the rate ventricle is paced after the other ventricle.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: January 27, 2009
    Assignee: Cardiac Pacemakers, Inc.
    Inventors: Jeffrey E. Stahmann, Andrew P. Kramer, Julio C. Spinelli
  • Patent number: 7480529
    Abstract: An implantable medical device includes an arrhythmia detection and classification system that classifies an arrhythmia episode based on an irregularity parameter and/or a complexity parameter. The arrhythmia episode is detected from a cardiac signal. The irregularity parameter is indicative of the degree of cycle length irregularity of the cardiac signal and the complexity parameter is indicative of the degree of morphological complexity of the cardiac signal. One example of the irregularity parameter is an irregularity sample entropy, or a parameter related to the irregularity sample entropy, computed to indicate the cycle length irregularity. One example of the complexity parameter is a complexity sample entropy, or a parameter related to the complexity sample entropy, computed to indicate the morphological complexity. In one embodiment, the detected arrhythmia episode is classified using both the irregularity parameter and the complexity parameter.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: January 20, 2009
    Assignee: Cardiac Pacemakers, Inc.
    Inventor: Dan Li
  • Publication number: 20090018459
    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.
    Type: Application
    Filed: July 9, 2007
    Publication date: January 15, 2009
    Inventors: Chi-jen Tseng, Wei-min Brian Chiu
  • Patent number: 7477936
    Abstract: A system or a method for analysing ECG curvature wherein at least one among a number of different parameters is isolated, for indicating symptoms of diseases having influence on the ECG curvature. The system and method provides for objective, fast and effective indication of a number of symptoms derivable from an ECG curve which may be indicative of one or more diseases. This can be achieved when a first number of selected parameters are combined in at least a first mathematical analysis, where the result of the analysis can be represented as a point in a coordinate system comprising at least two axes where the system can compare the actual placement in the coordinate system with a number of reference parameters stored in the system for indicating diseases having influence on the ECG curvature.
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: January 13, 2009
    Assignee: Aalborg Universitet
    Inventors: Thomas Bork Hardahl, Claus Graff, Mads Peter Andersen, Egon Toft, Johannes Jan Struijk, Jørgen Kim Kanters
  • Patent number: 7463926
    Abstract: A system for automatically evaluating the sensing and detection of physiological processes by an implantable medical device, such as an implantable cardiac stimulation device. The system includes an automatic testing algorithm which iteratively adjusts at least one of the threshold and gain settings of the device and evaluates the accuracy of the detection for refining the programming of the device. The algorithm can include sampling the physiological process beginning at a relatively low rate to avoid excessive burden on the processing and battery capacity available and progressively increasing the rate to obtain higher resolution data. The algorithm can also evaluate the observed physiological process for periodicity and can determine repetition of an irregular pattern, such as bigeminy, and use the determined pattern for predictive purposes to refine the programming of the device. The algorithm employs observation of a change in observed pattern as indicia for loss of proper detection.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: December 9, 2008
    Assignee: Pacesetter, Inc.
    Inventors: Paul A. Levine, Arndt Godau
  • Patent number: 7460902
    Abstract: A method and system for monitoring atrial activation in a patient is provided. In the method, a moment of occurrence and a wave form are predicted for a subsequent P wave based on a sequence of P waves already received in ECG signal data obtained from the patient. The process then checks whether the subsequent P wave really occurs in the ECG signal data within a first time window around the predicted moment of occurrence. If this is the case, the process further monitors whether the P wave is followed by a QRS complex in the ECG signal data.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: December 2, 2008
    Assignee: The General Electric Company
    Inventor: Mikko Kaski
  • Publication number: 20080262366
    Abstract: A method and apparatus for measuring the QT interval of an electrocardiogram (ECG) signal is provided wherein the end of the T wave is identified from ECG data. The end of the T wave is defined as the first time of intersection at which an upright T wave of a first set of derived ECG signal data intersects an inverted T wave of a second set of derived ECG signal data. The intersection of the two sets of ECG data is along an isoelectric line within the trough after the positive T wave peak when the superimposed isoelectric baselines from the upright and inverted ECG signals demonstrate the best least squares fit.
    Type: Application
    Filed: October 10, 2003
    Publication date: October 23, 2008
    Applicant: PSI HEartSignals (global) Limited
    Inventor: Anthony Charles Hunt
  • Publication number: 20080249425
    Abstract: A method and apparatus for defining cardiac time intervals using the pre-systolic diastolic filling period and the proceeding systolic period. The diastolic period can begin at the end of the T wave and terminate at the onset of the proceeding Q wave as defined in electrocardiograph signals. The systolic period can begin at onset of the Q peak and terminate at the end of the T wave as defined in electrocardiograph signals.
    Type: Application
    Filed: August 30, 2005
    Publication date: October 9, 2008
    Applicant: USCOM LIMITED
    Inventor: Robert Allan Phillips
  • Publication number: 20080221633
    Abstract: A method and a system for detection of an arrhythmia and discrimination between different types of arrhythmia to determine whether to administer an electric shock to the heart, the method comprising monitoring the electrical activity of a beating heart, selecting a number of heart beat intervals that will comprise an analysis segment; determining an instantaneous heart rate for each of the heart beat intervals with the segment; calculating the mean instantaneous heart rate for the segment; determining the variability of the instantaneous heart rates compared to a mean; using a linear combination of the mean and the non-linear value for comparison with a predetermined threshold to discriminate the type of arrhythmia to automatically decide if intervention is indicated.
    Type: Application
    Filed: May 22, 2008
    Publication date: September 11, 2008
    Applicant: UNIVERSITY OF WASHINGTON
    Inventor: David Thor Linker
  • Publication number: 20080214946
    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.
    Type: Application
    Filed: September 6, 2006
    Publication date: September 4, 2008
    Inventors: Robin Miller, Alison Burdett
  • Publication number: 20080194978
    Abstract: An apparatus for QRS waveform quantifying, comprising: an input unit, for receiving one or more high frequency (HF) range QRS complexes from one or more ECG leads, a primary analyzer, for calculating a primary index from the high frequency (HF) range QRS complex, and a secondary analyzer, connected after the primary analyzer, for deriving a secondary index from the primary index, thereby to provide a quantification of QRS complexes.
    Type: Application
    Filed: May 1, 2005
    Publication date: August 14, 2008
    Inventors: Amir Beker, Orna Bregman-Amitai, Alexander Zeltser
  • Publication number: 20080188763
    Abstract: A system for the detection of cardiac events occurring in a human patient is provided. At least two electrodes are included in the system for obtaining an electrical signal from a patient's heart. An electrical signal processor is electrically coupled to the electrodes for processing the electrical signal. The system determines the presence of a cardiovascular condition by applying a sliding scale rule to heart signal feature values. When the cardiovascular condition is ischemia, the ST segment may be analyzed. A sliding scale is applied to ST segment shifts such that when the magnitudes of ST segment shifts are relatively small, a larger number of beats is required to detect ischemia compared to the case when the magnitudes of ST shifts are large.
    Type: Application
    Filed: February 12, 2008
    Publication date: August 7, 2008
    Inventors: Michael Sasha John, David R. Fischell, Bruce Hopenfeld
  • Publication number: 20080183093
    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.
    Type: Application
    Filed: August 20, 2007
    Publication date: July 31, 2008
    Inventors: Jeng-Ren Duann, Tzyy-Ping Jung
  • Patent number: 7400920
    Abstract: Morphological features within electrical cardiac signals are tracked and changes in features are monitored to detect renal failure. The morphological feature may be an interval between corresponding polarization events such as the interval between QRS-complexes and peaks of corresponding T-waves (QTmax interval); the interval between QRS-complexes and ends of corresponding T-waves (QTend interval); or the interval between P-waves and corresponding QRS-complexes (PR interval). The feature may also be the elevation of a cardiac signal segment between corresponding polarization events, such as QRS-complexes and corresponding T-waves (ST segment); a duration of a polarization event, such as a QRS-complex (QRS width); or an amplitude of a polarization event, such as a T-wave (T-wave amplitude).
    Type: Grant
    Filed: August 11, 2005
    Date of Patent: July 15, 2008
    Assignee: Pacesetter, Inc.
    Inventors: Jong Gill, Gene A. Bornzin
  • Publication number: 20080161708
    Abstract: The present invention comprises methods and apparatus for detecting prolonged myocardial repolarization as an indicator of cardiac conditions, including without limitation, transmural ischemia. In some embodiments, without limitation, the present invention comprises methods and apparatus to detect prolonged repolarization using electrocardiographic and electrophysiological tools and measurements.
    Type: Application
    Filed: February 11, 2005
    Publication date: July 3, 2008
    Inventors: David N. Kenigsberg, Sanjaya Khanal, Marcin Kowalski, Subramaniam Krishnan
  • Publication number: 20080125665
    Abstract: An implantable medical device provides for improved storage of recorded IEGMs. A sensing stage is connected to an electrode for picking up electric potentials from inside a heart, the time course of said electric potentials representing a heart signal, a control unit connected to said sensing stage is adapted to process a sequence of data points that each represent an amplitude or magnitude A of a time-varying signal at equidistant points of time t, wherein end points of data segments are determined by processing of the sequence of data points. The control unit is adapted to identify end points of data segments by processing of the sequence of data points.
    Type: Application
    Filed: November 27, 2006
    Publication date: May 29, 2008
    Inventor: Indra B. Nigam
  • Publication number: 20080119748
    Abstract: Template formation methods for use in implantable cardiac rhythm management devices. In an illustrative method, a signal is captured in an implanted cardiac rhythm management device, and parameters for analysis of the captured signal are then defined. Then, in the example, additional signals can be captured and used to either verify or discard the captured signal defined parameters. The template formation methods provide for creating a robust template to compare with sensed cardiac complexes. Devices and systems configured to perform template formation and verification methods are also shown.
    Type: Application
    Filed: November 16, 2007
    Publication date: May 22, 2008
    Inventors: Surekha Palreddy, Jay A. Warren, Alan H. Ostroff
  • Patent number: 7376458
    Abstract: Template formation methods for use in implantable cardiac rhythm management devices. In an illustrative method, a signal is captured signal an implanted cardiac rhythm management device, and parameters for analysis of the captured signal are then defined. Then, in the example, additional signals can be captured and used to either verify or discard the captured signal defined parameters. The template formation methods provide for creating a robust template to compare with sensed cardiac complexes. Devices and systems configured to perform template formation and verification methods are also shown.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: May 20, 2008
    Assignee: Cameron Health, Inc.
    Inventors: Surekha Palreddy, Jay A. Warren, Alan H. Ostroff