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 high voltage subsystem to provide a defibrillation voltage to the patient through the plurality of defibrillator electrodes, and an impedance measurement circuit to measure an impedance across a first pair of ECG electrodes, wherein the impedance measurement circuit is to apply a balancing impedance across a second pair of ECG electrodes when an impedance of the second pair of ECG electrodes is not being measured.

Abstract: Embodiments of a wearable cardioverter defibrillator (WCD) system are configured to monitor a patient's ECG for shockable arrhythmias and deliver a shock to the patient in response to such a detection. To monitor the patient's ECG with reduced signal noise to improve the system's performance, the system includes a cable assembly having: a signal line; an inner shield and an outer shield; an ECG electrode electrically connected to the signal line of the cable assembly; and an amplifier having first and second input nodes respectively connected to the signal line and the outer shield of the cable assembly. The amplifier's output node is electrically connected to the inner shield of the cable assembly to reduce the reactive load seen by the patient's heart in driving the ECG sensing circuitry, which reduces the noise on the ECG signal outputted by the amplifier.

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 high voltage subsystem to provide a defibrillation voltage to the patient through the plurality of defibrillator electrodes, and an impedance measurement circuit to measure an impedance across a first pair of ECG electrodes, wherein the impedance measurement circuit is to apply a balancing impedance across a second pair of ECG electrodes when an impedance of the second pair of ECG electrodes is not being measured.

Abstract: Embodiments of a wearable cardioverter defibrillator (WCD) system are configured to monitor a patient's ECG for shockable arrhythmias and deliver a shock to the patient in response to such a detection. To monitor the patient's ECG with reduced signal noise to improve the system's performance, the system includes a cable assembly having: a signal line; an inner shield and an outer shield; an ECG electrode electrically connected to the signal line of the cable assembly; and an amplifier having first and second input nodes respectively connected to the signal line and the outer shield of the cable assembly. The amplifier's output node is electrically connected to the inner shield of the cable assembly to reduce the reactive load seen by the patient's heart in driving the ECG sensing circuitry, which reduces the noise on the ECG signal outputted by the amplifier.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: Embodiments of a wearable cardioverter defibrillator (WCD) system are configured to monitor a patient's ECG for shockable arrhythmias and deliver a shock to the patient in response to such a detection. To monitor the patient's ECG with reduced signal noise to improve the system's performance, the system includes a cable assembly having: a signal line; an inner shield and an outer shield; an ECG electrode electrically connected to the signal line of the cable assembly; and an amplifier having first and second input nodes respectively connected to the signal line and the outer shield of the cable assembly. The amplifier's output node is electrically connected to the inner shield of the cable assembly to reduce the reactive load seen by the patient's heart in driving the ECG sensing circuitry, which reduces the noise on the ECG signal outputted by the amplifier.

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 high voltage subsystem to provide a defibrillation voltage to the patient through the plurality of defibrillator electrodes, and an impedance measurement circuit to measure an impedance across a first pair of ECG electrodes, wherein the impedance measurement circuit is to apply a balancing impedance across a second pair of ECG electrodes when an impedance of the second pair of ECG electrodes is not being measured.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: Devices, systems, and methods are disclosed that identify a type of cable coupled to a receptacle of a defibrillator and that activate one or both of an ECG monitoring module and an energy storage circuit based at least in part on the identified cable type. The cable-type identification may allow a defibrillator to, for example, operate in either or both of an ECG monitoring mode and/or a therapy mode, based on the type of cable that is coupled to the defibrillator. The disclosed devices, systems, and methods can monitor an ECG of a patient and deliver defibrillation therapy to the patient, depending on the type of cable coupled to the defibrillator and/or the type of detected ECG signal of the patient.

Abstract: Devices, systems, and methods are disclosed that identify a type of cable coupled to a receptacle of a defibrillator and that activate one or both of an ECG monitoring module and an energy storage circuit based at least in part on the identified cable type. The cable-type identification may allow a defibrillator to, for example, operate in either or both of an ECG monitoring mode and/or a therapy mode, based on the type of cable that is coupled to the defibrillator. The disclosed devices, systems, and methods can monitor an ECG of a patient and deliver defibrillation therapy to the patient, depending on the type of cable coupled to the defibrillator and/or the type of detected ECG signal of the patient.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: Embodiments of a WCD system include a measurement circuit that can render a physiological input from the patient. Such WCD systems may also receive a motion detection input that reveals whether a motion event has been detected by a motion detector. In some embodiments, a value becomes assigned to a motion level parameter in response to any motion event detected or not, and the rhythm analysis can be based on the physiological input and on the assigned value. In some embodiments, a rhythm analysis of the physiological input may be performed in different manners, depending on whether or not a motion event has been detected. In some embodiments, a different shock/no shock criterion may be applied to the rhythm analysis, depending on whether or not a motion event has been detected. The patient may receive an electrical shock according to a shock/no shock determination.

Abstract: Devices, systems, and methods are disclosed that identify a type of cable coupled to a receptacle of a defibrillator and that activate one or both of an ECG monitoring module and an energy storage circuit based at least in part on the identified cable type. The cable-type identification may allow a defibrillator to, for example, operate in either or both of an ECG monitoring mode and/or a therapy mode, based on the type of cable that is coupled to the defibrillator. The disclosed devices, systems, and methods can monitor an ECG of a patient and deliver defibrillation therapy to the patient, depending on the type of cable coupled to the defibrillator and/or the type of detected ECG signal of the patient.

Abstract: Techniques for determining whether one or more leads are not adequately connected to a patient, e.g., for ECG monitoring, are described. The techniques involve injection of an integrated signal (which includes a test signal) into one lead, and monitoring the driven lead and the response at the other leads, including the common mode and the difference between the other leads. These “lead-off” detection techniques may be provided by an external defibrillator that provides three-wire ECG monitoring. Techniques for determining a type of a cable coupled to a defibrillator are also described. The cable-type identification may allow a defibrillator to, for example, operate in either a three-wire ECG monitoring mode or a therapy mode, based on whether a three-wire ECG cable or a defibrillation cable is coupled to the defibrillator.

Abstract: Techniques for determining whether one or more leads are not adequately connected to a patient, e.g., for ECG monitoring, are described. The techniques involve injection of an integrated signal (which includes a test signal) into one lead, and monitoring the driven lead and the response at the other leads, including the common mode and the difference between the other leads. These “lead-off” detection techniques may be provided by an external defibrillator that provides three-wire ECG monitoring. Techniques for determining a type of a cable coupled to a defibrillator are also described. The cable-type identification may allow a defibrillator to, for example, operate in either a three-wire ECG monitoring mode or a therapy mode, based on whether a three-wire ECG cable or a defibrillation cable is coupled to the defibrillator.

Abstract: Techniques for determining whether one or more leads are not adequately connected to a patient, e.g., for ECG monitoring, are described. The techniques involve injection of an integrated signal (which includes a test signal) into one lead, and monitoring the driven lead and the response at the other leads, including the common mode and the difference between the other leads. These “lead-off” detection techniques may be provided by an external defibrillator that provides three-wire ECG monitoring. Techniques for determining a type of a cable coupled to a defibrillator are also described. The cable-type identification may allow a defibrillator to, for example, operate in either a three-wire ECG monitoring mode or a therapy mode, based on whether a three-wire ECG cable or a defibrillation cable is coupled to the defibrillator.