Abstract: In one aspect, an example wearable cardioverter defibrillator (WCD) system implementing the disclosed techniques includes a support structure, the support structure configured to be worn by a subject. The WCD system also includes a consciousness detection module configured to determine whether the subject wearing the support structure is unconscious. The WCD system further includes an interactive bystander module configured to, responsive to a determination that the subject wearing the support structure is unconscious, generate a first voice prompt inquiring as to a presence of a bystander.

Abstract: A wearable cardioverter defibrillator (WCD) comprises a plurality of electrocardiography (ECG) electrodes. An episode is opened responsive to a string of consecutive segments meeting one or more shock criteria, and a shockable rhythm is confirmed for the episode responsive to a subsequent string of consecutive segments meeting one or more confirmation criteria.

Abstract: In one embodiment, a method to detect noise levels in electrocardiogram (ECG) signals. The method includes connecting to at least three sensing electrodes and obtaining a signal from each of the at least three sensing electrodes. The method also includes defining at least three channels between the at least three electrodes and obtaining heart data for a predetermined time period from the at least three channels wherein the heart data includes heart rate and QRS width. The method further includes comparing the heart data of each of the at least three channels to a consistency threshold.

Abstract: A wearable vital signs monitor (WVSM) comprises one or more sensors to obtain one or more patient signals measured from a patient, and a processor to receive the one or more measured patient signals. The processor is configured to analyze the one or more patient signals against one or more criteria sets, determine whether at least one of the criteria sets is met, and if at least criteria set is met, cause a requested action to be performed. The requested action can comprise a least one of obtaining one or more additional patient signal measurements as defined by a patient signal measurement set corresponding to the met criteria set or performing one or more alert actions according to the met criteria set.

Abstract: In some embodiments, a wearable cardioverter defibrillator (“WCD”) system comprises a support structure configured to be worn by a patient, a power source, an energy storage module configured to be coupled to the support structure, to be charged from the power source and to store an electrical charge, a discharge circuit coupled to the energy storage module, the discharge circuit controllable to discharge the electrical charge so as to cause a shock to be delivered to the patient, a measurement circuit configured to render a physiological input from a patient physiological signal, a user interface configured to output one or more human-perceptible indications, and a processor.

Abstract: A portable medical device having improved ECG trace display and reporting. Embodiments implement features to ameliorate artifacts created by virtue of attempting to eliminate compression artifacts due to mechanical compression devices. Other embodiments additionally implement features to seek to detect the occurrence of ROSC while chest compressions are ongoing.

Abstract: A wearable cardioverter defibrillator (WCD) comprises a plurality of electrocardiography (ECG) electrodes, a right-leg drive (RLD) electrode, and a plurality of defibrillator electrodes to contact the patient's skin when the WCD is delivering therapy to the patient, a preamplifier coupled to the ECG electrodes and the RLD electrode to obtain ECG data from the patient as one or more ECG vectors, a processor to receive ECG data from the preamplifier and an abort signal from a user interface, an isolation barrier to isolate the preamplifier from the processor, and a high voltage subsystem to provide a defibrillation voltage to the patient through the defibrillator electrodes in response to a shock signal received from the processor. A shock is provided when an abort signal is not received within a predetermined time period of a shock criterion being met. Less than one false alarm occurs every ten patient-days.

Abstract: A wearable cardioverter defibrillator (WCD) including 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, a user interface configured to output an alarm in response to a noise alarm signal, and a processor. The processor is configured to receive the ECG signal, determine whether noise is present on the ECG signal, determine from the ECG signal whether a shock criterion is met, and cause the user interface to generate the noise alarm signal when the noise is present on the ECG signal and the shock criterion is met and not generate the noise alarm signal when noise is present on the ECG signal and the shock criterion is not met.

Abstract: A medical device such as an external defibrillator delivers electrical therapy using a special pulse sequence. The special pulse sequence includes a defibrillation shock that is automatically followed by a quick succession of automatic post-shock anti-tachycardia (APSAT) pacing pulses. Because of the pacing pulses, the defibrillation shock can be of lesser energy than an equivalent defibrillation shock of a larger energy. Accordingly, the external defibrillator can be made physically smaller and weigh less, without sacrificing the therapeutic effect of a larger external defibrillator that would deliver a defibrillation shock of higher energy. As such, the defibrillator is easier to configure for transporting, handling, and even wearing.

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.

Abstract: A wearable cardioverter defibrillator (WCD) having a processor configured to receive a signal indicating a position and/or movement of the ambulatory patient while the ambulatory patient is wearing the support structure receive the ECG signal, determine from an ECG signal whether a shock criterion is met, determine a confirmation time period and/or a response time period based on the position and/or movement of the ambulatory patient, determine from the ECG signal whether the shock criterion is met after the confirmation time period has elapsed, cause the user interface to generate the shock alert signal based on the shock criterion determined after the confirmation time period has elapsed, and control the discharge circuit to discharge the stored electrical charge when a predetermined time period has elapsed after the shock alert signal.

Abstract: In embodiments, a Wearable Cardioverter Defibrillator (WCD) system includes a support structure for the patient to wear, and components that the support structure maintains on the patient's body. The components include a defibrillator, associated electrodes, and so on. The defibrillator can operate in a WCD mode while the patient wears the support structure. The defibrillator can further operate in a different, AED mode, during which time the patient need not wear a portion of the support structure, or even the entire support structure. Sometimes the AED mode is a type of a fully automatic AED mode. Other times the AED mode is a type of a semi-automated AED mode, where an attendant is present to administer the shock; at such times, the patient may not even need to have electrodes attached. This way the patient is more comfortable for a longer time.

Abstract: A wearable cardioverter defibrillator (WCD) comprises a plurality of electrocardiography (ECG) electrodes, a right-leg drive (RLD) electrode, and a plurality of defibrillator electrodes to contact the patient's skin when the WCD is delivering therapy to the patient, a preamplifier coupled to the ECG electrodes and the RLD electrode to obtain ECG data from the patient as one or more ECG vectors, a processor to receive ECG data from the preamplifier and an abort signal from a user interface, an isolation barrier to isolate the preamplifier from the processor, and a high voltage subsystem to provide a defibrillation voltage to the patient through the defibrillator electrodes in response to a shock signal received from the processor. A shock is provided when an abort signal is not received within a predetermined time period of a shock criterion being met. Less than one false alarm occurs every ten patient-days.

Abstract: A wearable cardioverter defibrillator (WCD) including 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, a user interface configured to output an alarm in response to a noise alarm signal, and a processor. The processor is configured to receive the ECG signal, determine whether noise is present on the ECG signal, determine from the ECG signal whether a shock criterion is met, and cause the user interface to generate the noise alarm signal when the noise is present on the ECG signal and the shock criterion is met and not generate the noise alarm signal when noise is present on the ECG signal and the shock criterion is not met.

Abstract: A portable medical device having improved ECG trace display and reporting. Embodiments implement features to ameliorate artifacts created by virtue of attempting to eliminate compression artifacts due to mechanical compression devices. Other embodiments additionally implement features to seek to detect the occurrence of ROSC while chest compressions are ongoing.

Abstract: A wearable cardioverter defibrillator (WCD) having a processor configured to receive a signal indicating a position and/or movement of the ambulatory patient while the ambulatory patient is wearing the support structure receive the ECG signal, determine from an ECG signal whether a shock criterion is met, determine a confirmation time period and/or a response time period based on the position and/or movement of the ambulatory patient, determine from the ECG signal whether the shock criterion is met after the confirmation time period has elapsed, cause the user interface to generate the shock alert signal based on the shock criterion determined after the confirmation time period has elapsed, and control the discharge circuit to discharge the stored electrical charge when a predetermined time period has elapsed after the shock alert signal.

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.

Abstract: An external defibrillator system such as a WCD is also capable of providing transthoracic pacing and drug delivery (e.g., pain-reducing drugs and/or a sedatives) to a patient. The drug(s) may be included in the therapy electrode electrolyte and dispensed for defibrillation, cardioversion and/or pacing therapy. Alternatively, the drug(s) may be stored in a separate reservoir and dispensed during pacing therapy. The drug(s) may be dispensed to a patient after a successful defibrillation therapy. The pacing therapy may be delivered a set time-period after the drug(s) were dispensed. A relatively small electric current may be delivered to the area of the patient on which the drug(s) were dispensed to facilitate drug absorption.

Abstract: In embodiments, a Wearable Cardioverter Defibrillator (WCD) system includes a support structure for the patient to wear, and components that the support structure maintains on the patient's body. The components include a defibrillator, associated electrodes, and so on. The defibrillator can operate in a WCD mode while the patient wears the support structure. The defibrillator can further operate in a different, AED mode, during which time the patient need not wear a portion of the support structure, or even the entire support structure. Sometimes the AED mode is a type of a fully automatic AED mode. Other times the AED mode is a type of a semi-automated AED mode, where an attendant is present to administer the shock; at such times, the patient may not even need to have electrodes attached. This way the patient is more comfortable for a longer time.

Abstract: A wearable cardioverter defibrillator system includes a support structure that a patient can wear. The system also includes electrodes that contact the patient, and define two or more channels from which ECG signals are sensed. A processor may evaluate the channels by analyzing their respective ECG signals, to determine which contains less noise than the other(s). The analysis can be by extracting statistics from the ECG signals, optionally after first processing them, and then by comparing these statistics. These statistics may include tall peak counts, amplitudes of peaks compared to historical peak amplitudes, signal baseline shift, dwell time near a baseline, narrow peak counts, zero crossings counts, determined heart rates, and so on. Once the less noisy signal is identified, its channel can be followed preferentially or to the exclusion of other channels, for continuing monitoring and/or determining whether to shock the patient.