Wearable cardioverter defibrillator components discarding ecg signals prior to making shock/no shock determination based on correlation

Abstract

Components of wearable cardiac defibrillator (WCD) systems, software, and methods are provided. A WCD system includes a support structure that a patient can wear and electrodes that can capture at least two of the patient's ECG signals. A component includes an energy storage module that can store an electrical charge, a discharge circuit, and a processor that can make a shock/no shock determination, and cause the discharge circuit to discharge the stored charge, if the determination is to shock. In some embodiments, the processor discards at least one of the ECG signals prior to making the shock/no shock determination. The determination can be made from the remaining one or more ECG signals. In some embodiments, the processor makes an aggregate shock/no shock determination from two or more of the ECG signals.

1 - 93 . (canceled) 
     
     
         94 . A component of a wearable cardiac defibrillation (WCD) system, the WCD system including a support structure configured to be worn by a patient, sensing electrodes configured to capture at least three ElectroCardioGram (ECG) signals of the patient, and defibrillation electrodes configured to transport electrical charge, the component comprising:
 an accelerometer configured to generate an acceleration signal;   an energy storage module configured to store an electrical charge;   a discharge circuit coupled to the energy storage module; and   a processor configured to:
 decide whether at least a certain one of the at least three ECG signals meets a reliability criterion and, if not, to discard it, the reliability criterion for the certain ECG signal being derived from a mathematical correlation between the acceleration signal and the certain ECG signal, 
 make a shock/no shock determination from one of the ECG signals that is not the discarded ECG signal, and 
 cause, if the determination is to shock, the discharge circuit to discharge the stored electrical charge through at least two of the defibrillation electrodes so as to defibrillate the patient. 
   
     
     
         95 . The component of  claim 94 , in which
 the mathematical correlation includes a cross-correlation, and   the acceleration signal and the certain ECG signal are simplified before the cross-correlation.   
     
     
         96 . The component of  claim 94 , in which
 all the ECG signals are discarded except one.   
     
     
         97 . The component of  claim 96 , in which
 the shock/no shock determination is not made if the non-discarded ECG signal has a reliability value that is less than a threshold.   
     
     
         98 . The component of  claim 94 , in which
 the shock/no shock determination is made from a patient heart rate detected in the ECG signal.   
     
     
         99 . The component of  claim 94 , in which
 the reliability criterion is not met if two others of the ECG signals have an aspect similar to each other.   
     
     
         100 . A non-transitory computer-readable storage medium storing one or more programs which, when executed by at least one processor of a wearable cardiac defibrillation (WCD) system, the WCD system including a support structure configured to be worn by a patient, sensing electrodes configured to capture at least three ECG signals of the patient, an accelerometer configured to generate an acceleration signal, an energy storage module configured to store an electrical charge, and a discharge circuit coupled to the energy storage module, the one or more programs result in:
 deciding whether at least a certain one of the at least three ECG signals meets a reliability criterion and, if not, to discard it, the reliability criterion for the certain ECG signal being derived from a mathematical correlation between the acceleration signal and the certain ECG signal,   making a shock/no shock determination from one of the ECG signals that is not the discarded ECG signal, and   causing, if the determination is to shock, the discharge circuit to discharge the stored electrical charge through at least two of the defibrillation electrodes so as to defibrillate the patient.   
     
     
         101 . The medium of  claim 100 , in which
 the mathematical correlation includes a cross-correlation, and   the acceleration signal and the certain ECG signal are simplified before the cross-correlation.   
     
     
         102 . The medium of  claim 100 , in which
 all the ECG signals are discarded except one.   
     
     
         103 . The medium of  claim 102 , in which
 the shock/no shock determination is not made if the non-discarded ECG signal has a reliability value that is less than a threshold.   
     
     
         104 . The medium of  claim 100 , in which
 the shock/no shock determination is made from a patient heart rate detected in the ECG signal.   
     
     
         105 . The medium of  claim 100 , in which
 the reliability criterion is not met if two others of the ECG signals have an aspect similar to each other.   
     
     
         106 . A method for a component of a wearable cardiac defibrillation (WCD) system, the WCD system including a support structure configured to be worn by a patient, sensing electrodes configured to capture at least three ECG signals of the patient, an accelerometer configured to generate an acceleration signal, an energy storage module configured to store an electrical charge, and a discharge circuit coupled to the energy storage module, the method comprising:
 deciding whether at least a certain one of the at least three ECG signals meets a reliability criterion and, if not, to discard it, the reliability criterion for the certain ECG signal being derived from a mathematical correlation between the acceleration signal and the certain ECG signal,   making a shock/no shock determination from one of the ECG signals that is not the discarded ECG signal, and   causing, if the determination is to shock, the discharge circuit to discharge the stored electrical charge through at least two of the defibrillation electrodes so as to defibrillate the patient.   
     
     
         107 . The method of  claim 106 , in which
 the mathematical correlation includes a cross-correlation, and   the acceleration signal and the certain ECG signal are simplified before the cross-correlation.   
     
     
         108 . The method of  claim 106 , in which
 all the ECG signals are discarded except one.   
     
     
         109 . The method of  claim 108 , in which
 the shock/no shock determination is not made if the non-discarded ECG signal has a reliability value that is less than a threshold.   
     
     
         110 . The method of  claim 106 , in which
 the shock/no shock determination is made from a patient heart rate detected in the ECG signal.   
     
     
         111 . The method of  claim 106 , in which
 the reliability criterion is not met if two others of the ECG signals have an aspect similar to each other.