Cardiac Science Corporation

Braemar Manufacturing LLC

Cardionet, Inc.

Dongping Lin

Prabodh Mathur

Raul Ybarra

Charles Gropper

Yachuan Pu

Xu-Sheng Zhang

David J Clark

Gary P Mezack

Srikanth Thiagarajan

Mike Norton

Patrick Bradley

Raymond W Cohen

David Clark

A machine-implemented method including obtaining physiological signal data for a living being and performing a first analysis of the physiological signal data at a processing device local to the living being and remote from a central processing device. The method further includes transmitting from the processing device data associated with the analysis to the central processing device and performing at the central processing device a second analysis of the data associated with the first analysis. The method further includes displaying the data associated with the second analysis. The method can also include interaction between the processing device local to the living being and the central processing device. The method can also include distributing monitoring and analysis between an ambulatory and a centralized subsystem.

Ambulatory and centralized processing of a physiological signal

Systems, methods, apparatus, and computer program products for detecting the existence of a sleep disorder in an individual using heart activity. In one aspect, machine-implemented methods include the actions of analyzing a machine-readable heart rate series of a monitored individual in the time domain using one or more digital data processing devices, detecting a cyclic variation in heart rate in the heart rate series as a result of the analysis in the time domain, and outputting, over an output, a report characterizing a sleep disorder event based on the detection of the cyclic variation in heart rate in the heart rate series. The cyclic variation in heart rate is indicative of a sleep disorder.

Detecting sleep disorders using heart activity

Systems, devices, methods, and techniques relating to the identification of fiducial points. In one aspect, a machine implemented method includes obtaining a first time varying physiological signal and a second time varying physiological signal that relate to biological activity of an organism, the first time varying physiological signal and the second time varying physiological signal forming an analytic pair wherein the analytic pair has a time varying phase angle, defining a reference line by a lower boundary of a representation of the time varying phase angle with respect to a time period, and identifying a fiducial point based on the reference line.

Locating fiducial points in a physiological signal

A defibrillator module is described which includes a cardiac sensor, a pulse generator and a controller that generates commands responsive to intrinsic cardiac signals for the operation of said pulse generator. The defibrillator module synergistic and arranged so that it can be coupled to a generic patient monitor so that the two can share certain functions. For example, operational parameters and other signals indicative of the operation of the defibrillator module can be shown to the clinician by the patient monitor. Data between the defibrillator module and the patient monitor is exchanged using either a standard or a customized protocol.

Automatic defibrillator module for integration with standard patient monitoring equipment

A publically available external defibrillator includes a detector used to detect a life threatening condition of a patient, a controller operating the defibrillator automatically and a therapy delivery circuit that delivers appropriate therapy. The defibrillator is attached to a patient by any attendant or bystander and once it is attached, the defibrillator is adapted to monitor the patient and when a life threatening condition is detected, to apply therapy automatically, i.e., without any involvement by the patient or the attendant.

Public access defibrillator

A system to detect the presence or absence of T wave alternans is described based on statistical tests and periodicity transform. T wave and ST segment boundaries are detected in multi-lead ECG signals acquired from the regular clinical leads. Once the fiducial point and the above boundaries are delineated, computation of regular parameters like T wave amplitude, area under the T waves or segments of T wave, ST segment slope and/or the curvature of T wave are performed. Each parameter forms a rolling array of values with each successive beat. The array of values, or the time series, is used to make the decision about the T wave alternans. Two different methods are employed based on periodicity transforms and statistical tests. A set of numerical values (e.g. norm of the projection on to p-2 space, sums of adjacent terms after the trend removal, t-value, and number of deviations from alternans pattern) are all computed and compared to threshold values. Threshold values are computed from past information and experience with clinical databases and simulations. Final system comprises a software module, which can be part of the existing ECG monitoring programs as well as external defibrillator modules, apart from being stand-alone algorithms.

Method and apparatus for monitoring cardiac patients for T-wave alternans

A system and method based on electrocardiogram (ECG) complexity analysis for real-time detecting shockable ventricular fibrillation (VF) and ventricular tachycardia (VT), and discriminating them from non-shockable tachyarrhythmia (e.g. supraventricular tachycardia (SVT) and atrial fibrillation (AF)) and high-frequency noise. In the disclosed invention, complexity measure CM (0 to 100), quantitatively characterizing the complexity nature of the non-linear dynamics underlying cardiac arrhythmia, is extracted from the sensed patient ECG signal using ECG complexity analysis. From the calculated complexity measure, by three thresholds (low complexity threshold (LCT), mediate complexity threshold (MCT), and high complexity threshold (HCT)), different kinds of tachyarrhythmia (i.e. heart rate (HR) above a preset rate threshold) and high-frequency noise are discriminated from each other: for non-shockable tachyarrhythmia, CM&lE;LCT; for VT, LCT<CM&lE;MCT; for VF, MCT<CM&lE;HCT; and for high-frequency noise, HCT<CM. The disclosed system and method can be used as a primary cardiac tachyarrhythmia detection scheme or as a backup system to reconfirm arrhythmia detection using conventional techniques.

System and method for complexity analysis-based cardiac tachyarrhythmia detection

A cardiac monitor is provided that monitors the condition of the heart of a cardiac patient and generates signals indicating one of several conditions, such as supraventricular tachycardia, ventricular tachycardia and ventricular fibrillation. In order to generate these signals, the ECG from the patient is analyzed to determine a cardiac interval and heart rate, as well as a waveform factor and a waveform factor irregularity. The waveform factor is derived from the average of the ECG amplitudes during a cardiac interval and the peak value of the ECG during the same interval. Preferably, a running average is calculated over several intervals. This waveform factor is then used to detect shockable ventricular arrhythmia. The waveform factor irregularity is indicative of the variability of the waveform factor and is used to differentiate between ventricular tachycardia and ventricular defibrillation.

Cardiac arrhythmia detector using ECG waveform-factor and its irregularity

An external defibrillator includes a detector used to detect a life threatening condition of a patient, a controller operating the defibrillator automatically and a therapy delivery circuit that delivers appropriate therapy. Advantageously a parameter is derived from the cardiac signals sensed in the patient, the parameters being used to differentiate between shockable events such as ventricular tachyarrhythmia and other events such as SVT. The defibrillator is attached to a patient by an attendant and once it is attached, the defibrillator is adapted to monitor the patient and when a life threatening condition is detected, to apply therapy automatically, i.e., without any involvement by the patient or the attendant.

Automatic external cardioverter/defibrillator with tachyarrhythmia detector using a modulation (amplitude and frequency) domain function

An external defibrillator includes a detector used to detect a life threatening condition of a patient, a controller operating the defibrillator automatically and a therapy delivery circuit that delivers appropriate therapy. The defibrillator is attached to a patient and is adapted to monitor the patient and when a life threatening condition is detected, to apply therapy automatically. An averaging scheme is used to determine a current cardiac rate by taking a first average of the intervals between a preset number of successive cardiac events, establishing a differential between this average and the intervals, dropping the interval corresponding to the largest differential. In this manner, the effects of over- and undersensing are eliminated or at least reduced.

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Irvine, CA, United States of America

Dongping Lin