Wearable cardioverter defibrillator (WCD) system detecting QRS complexes in ECG signal by matched difference filter
AssigneeWest Affum Holdings Corp.
InventorJoseph L. Sullivan
Life of this patent
Estimating the term…
Abstract
In embodiments, a wearable cardioverter defibrillator (WCD) system includes electrodes that render an ECG signal of the patient, and a processor that receives ECG data are derived from the rendered ECG signal. The processor may filter the received ECG data with a matched difference filter to detect QRS complexes, and compute a heart rate from the detected QRS complexes. The matched difference filter itself can have coefficient values associated with a baseline QRS complex, which improves detection.
Claims38
A wearable cardioverter defibrillator (WCD) system, comprising:
- a support structure configured to be worn by an ambulatory patient;
- an energy storage module configured to store an electrical charge;
- a discharge circuit coupled to the energy storage module;
- electrodes configured to render an electrocardiogram (ECG) signal of the patient while the patient is wearing the support structure;
- and
- a processor configured to:
- receive ECG data that are derived from the rendered ECG signal, the ECG data having values f(m),
- compute, from the values f(m), outputs for multiple values of a positive integer n according to an equation comprising a matched difference term (MDT) where, in the equation, MDT is a matched difference term that is a function of a difference of a first function F[] of the values f(m) and of a second function G[] of coefficient values g(m) that are associated with a baseline QRS complex,
- detect QRS complexes from the computed outputs,
- compute a heart rate from the detected QRS complexes,
- determine, from the computed heart rate, whether or not a shock criterion is met, and
- control, responsive to the shock criterion being met, the discharge circuit to discharge the stored electrical charge through the patient while the support structure is worn by the patient so as to deliver a shock to the patient.
A non-transitory computer-readable storage medium storing one or more programs which, when executed by at least one processor of a wearable cardioverter defibrillator (WCD) system, the WCD system including a support structure configured to be worn by an ambulatory patient, an energy storage module storing an electrical charge, a discharge circuit coupled to the energy storage module and electrodes configured to render an electrocardiogram (ECG) signal of the patient while the patient is wearing the support structure, these one or more programs result in operations comprising:
- receiving ECG data that are derived from the rendered ECG signal, the ECG data having values f(m);
- computing, from the values f(m), outputs for multiple values of a positive integer n according to an equation comprising a matched difference term (MDT) where, in the equation, MDT is a matched difference term that is a function of a difference of a first function F[] of the values f(m) and of a second function G[] of coefficient values g(m) that are associated with a baseline QRS complex;
- detecting QRS complexes from the computed outputs;
- computing a heart rate from the detected QRS complexes;
- determining, from the computed heart rate, whether or not a shock criterion is met;
- and
- controlling, responsive to the shock criterion being met, the discharge circuit to discharge the stored electrical charge through the patient while the support structure is worn by the patient so as to deliver a shock to the patient.
A method for a wearable cardioverter defibrillator (WCD) system, the WCD system including a support structure configured to be worn by an ambulatory patient, an energy storage module storing an electrical charge, a discharge circuit coupled to the energy storage module and electrodes, the method comprising:
- rendering an electrocardiogram (ECG) signal of the patient while the patient is wearing the support structure;
- receiving ECG data that are derived from the rendered ECG signal, the ECG data having values f(m);
- computing, from the values f(m), outputs for multiple values of a positive integer n according to an equation comprising a matched difference term (MDT) where, in the equation, MDT is a matched difference term that is a function of a difference of a first function F[] of the values f(m) and of a second function G[] of coefficient values g(m) that are associated with a baseline QRS complex;
- detecting QRS complexes from the computed outputs;
- computing a heart rate from the detected QRS complexes;
- determining, from the computed heart rate, whether or not a shock criterion is met;
- and controlling, responsive to the shock criterion being met, the discharge circuit to discharge the stored electrical charge through the patient while the support structure is worn by the patient so as to deliver a shock to the patient.
A wearable cardioverter defibrillator (WCD) system, comprising:
- a support structure configured to be worn by a patient;
- an energy storage module configured to store an electrical charge;
- a discharge circuit coupled to the energy storage module;
- electrodes configured to output an electrocardiogram (ECG) signal of the patient while the patient is wearing the support structure;
- a heart rate detector to detect a heart rate of the patient;
- and
- a processor configured to:
- receive ECG data that are derived from the ECG signal, the ECG data having values f(m),
- compute, from the values f(m), outputs for multiple values of a positive integer n according to an equation comprising a matched difference term (MDT) where, in the equation, MDT is a matched difference term that is a function of a difference of a first function F[] of the values f(m) and of a second function G[] of coefficient values g(m) that are associated with a baseline QRS complex,
- detect QRS complexes from the computed outputs,
- compute a heart rate from the detected QRS complexes,
- determine, from the detected heart rate, whether or not a shock criterion is met,
- control, responsive to the shock criterion being met, the discharge circuit to discharge at least a portion of the stored electrical charge through the patient while the support structure is worn by the patient so as to deliver a shock to the patient;
- assess agreement between the detected heart rate and the computed heart rate, and
- update the MDT for subsequent computing of the outputs when agreement is high.
A method for a wearable cardioverter defibrillator (WCD) system, the WCD system including a support structure configured to be worn by a patient, an energy storage module storing an electrical charge, a discharge circuit coupled to the energy storage module and electrodes, and a heart rate detector to detect a heart rate of the patient, the method comprising:
- detecting a heart rate of the patient with the heart rate detector;
- outputting an electrocardiogram (ECG) signal of the patient while the patient is wearing the support structure;
- receiving ECG data that are derived from the ECG signal, the ECG data having values f(m);
- computing, from the values f(m), outputs for multiple values of a positive integer n according to an equation comprising a matched difference term (MDT) where, in the equation, MDT is a matched difference term that is a function of a difference of a first function F[] of the values f(m) and of a second function G[] of coefficient values g(m) that are associated with a baseline QRS complex;
- detecting QRS complexes from the computed outputs;
- computing a heart rate from the detected QRS complexes;
- determining, from the detected heart rate, whether or not a shock criterion is met;
- controlling, responsive to the shock criterion being met, the discharge circuit to discharge at least a portion of the stored electrical charge through the patient while the support structure is worn by the patient so as to deliver a shock to the patient;
- assessing agreement between the detected heart rate and the computed heart rate;
- and
- updating the MDT for subsequent computing of the outputs when agreement is high.
A wearable cardioverter defibrillator (WCD), comprising:
- a support structure configured to be worn by a patient;
- an energy storage module configured to store an electrical charge;
- a discharge circuit coupled to the energy storage module;
- electrodes configured to obtain an electrocardiogram (ECG) signal of the patient while the patient is wearing the support structure;
- and
- a processor configured to:
- process the ECG signal to detect a QRS complex in the ECG signal using an adaptive matched filter;
- compute a heart rate of the patient based at least at least in part on the detected QRS complex;
- determine based at least in part on the computed heat rate whether a shock criterion is met;
- and
- responsive to the shock criterion being met, control the discharge circuit to discharge at least a portion of the stored electrical charge through the patient while the support structure is worn by the patent to deliver a shock to the patient;
- wherein the processor is configured to:
- assess a quality of the ECG signal;
- and
- update a kernel of the adaptive matched filter when the quality of the ECG signal is high.
Dependencies are inferred from the claim text.