Abstract: Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous implantable cardioverter defibrillator (SICD) and a leadless pacing device (LPD) are described. For example, the SICD may detect a tachyarrhythmia within a first electrical signal from a heart and determine, based on the tachyarrhythmia, to deliver anti-tachyarrhythmia shock therapy to the patient to treat the detected arrhythmia. The LPD may receive communication from the SICD requesting the LPD deliver anti-tachycardia pacing to the heart and determine, based on a second electrical signal from the heart sensed by the LPD, whether to deliver anti-tachycardia pacing (ATP) to the heart. In this manner, the SICD and LPD may communicate to coordinate ATP and/or cardioversion/defibrillation therapy. In another example, the LPD may be configured to deliver post-shock pacing after detecting delivery of anti-tachyarrhythmia shock therapy.

Abstract: A medical device comprises a sensing circuit configured to sense at least one cardiac electrical signal, sense first ventricular event signals from the at least one cardiac electrical signal according to a sensitivity setting set to a first amplitude; and a control circuit in communication with the sensing circuit, the control circuit configured to determine that the at least one cardiac electrical signal meets suspected undersensing criteria, in response to determining that the suspected undersensing criteria are met, perform a morphology analysis of a first cardiac signal segment acquired from a first cardiac electrical signal of the at least one cardiac electrical signal sensed by the sensing circuit over a first predetermined time interval, determine that the first cardiac signal segment is a first tachyarrhythmia segment based on the morphology analysis, and adjust the sensitivity setting from the first amplitude to a second amplitude less than the first amplitude in response to determining that the firs

Abstract: A method and device apparatus to deliver a pacing therapy capable of remodeling a patient's heart over a period of time that includes monitoring one or more parameters in response to a delivered cardiac remodeling pacing, determining whether the cardiac remodeling pacing has an effect on cardiac normalization in response to the monitoring, and adjusting the cardiac remodeling pacing in response to the determined effect on cardiac normalization. The method and device may also perform short-term monitoring of one or more parameters in response to the delivered cardiac remodeling pacing, monitor one or more long-term parameter indicative of a long-term effect of the delivered cardiac remodeling pacing, determine the long-term effect of the delivered cardiac remodeling pacing on cardiac normalization in response to the monitoring, and adjust the cardiac remodeling pacing in response to one or both of the short-term monitoring and the determined long-term effect on cardiac normalization.

Abstract: A method for heart failure management includes monitoring one or more sensor-based parameters for a patient to determine a pacing therapy. If the one or more parameters indicate atrial tachycardia or atrial fibrillation, a first pacing therapy is delivered. If the one or more parameters do not indicate atrial tachycardia or atrial fibrillation, it is determined whether the patient is asleep. If the patient is asleep, a second pacing therapy is delivered. If the one or more parameters do not indicate atrial tachycardia, atrial fibrillation, or that the patient is asleep, the patient's P-wave duration is evaluated with respect to a P-wave duration threshold value. When the patient's P-wave duration is determined to exceed the P-wave duration threshold value, a third pacing therapy is delivered, and when the patient's P-wave duration is determined to not exceed the P-wave duration threshold value, a fourth pacing therapy is delivered.

Abstract: Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous implantable cardioverter defibrillator (SICD) and a leadless pacing device (LPD) are described. For example, the SICD may detect a tachyarrhythmia within a first electrical signal from a heart and determine, based on the tachyarrhythmia, to deliver anti-tachyarrhythmia shock therapy to the patient to treat the detected arrhythmia. The LPD may receive communication from the SICD requesting the LPD deliver anti-tachycardia pacing to the heart and determine, based on a second electrical signal from the heart sensed by the LPD, whether to deliver anti-tachycardia pacing (ATP) to the heart. In this manner, the SICD and LPD may communicate to coordinate ATP and/or cardioversion/defibrillation therapy. In another example, the LPD may be configured to deliver post-shock pacing after detecting delivery of anti-tachyarrhythmia shock therapy.

Abstract: An example medical device system includes therapy delivery circuitry configured to deliver anti-tachycardia pacing (ATP) therapy to a heart of a patient via electrodes communicatively coupled to the therapy delivery circuitry. The ATP therapy includes one or more ATP trains. The medical device system also includes processing circuitry configured determine a first propagation time based on a comparison of features in a local electrogram and a far-field electrogram, such as the time from a fiducial point in the local electrogram and QRS onset in the far-field electrogram. The processing circuitry is also configured to determine, based on the first propagation time, a number of pulses to achieve a second propagation time and control the therapy delivery circuitry to deliver the ATP train of at least the number of pulses.

Abstract: A method for heart failure management includes monitoring one or more sensor-based parameters for a patient to determine a pacing therapy. If the one or more parameters indicate atrial tachycardia or atrial fibrillation, a first pacing therapy is delivered. If the one or more parameters do not indicate atrial tachycardia or atrial fibrillation, it is determined whether the patient is asleep. If the patient is asleep, a second pacing therapy is delivered. If the one or more parameters do not indicate atrial tachycardia, atrial fibrillation, or that the patient is asleep, the patient's P-wave duration is evaluated with respect to a P-wave duration threshold value. When the patient's P-wave duration is determined to exceed the P-wave duration threshold value, a third pacing therapy is delivered, and when the patient's P-wave duration is determined to not exceed the P-wave duration threshold value, a fourth pacing therapy is delivered.

Abstract: Systems, devices, and methods for performing respiratory-based cardiac remodeling pacing therapy are described in this disclosure. A patent's respiration may be monitored, and the lower pacing limit for the cardiac remodeling pacing and support pacing therapy delivered to a patient may be adjusted based on the monitored respiration to achieve or restore respiratory sinus arrhythmia.

Abstract: Techniques and systems for monitoring cardiac arrhythmias and delivering electrical stimulation therapy using a subcutaneous implantable cardioverter defibrillator (SICD) and a leadless pacing device (LPD) are described. For example, the SICD may detect a tachyarrhythmia within a first electrical signal from a heart and determine, based on the tachyarrhythmia, to deliver anti-tachyarrhythmia shock therapy to the patient to treat the detected arrhythmia. The LPD may receive communication from the SICD requesting the LPD deliver anti-tachycardia pacing to the heart and determine, based on a second electrical signal from the heart sensed by the LPD, whether to deliver anti-tachycardia pacing (ATP) to the heart. In this manner, the SICD and LPD may communicate to coordinate ATP and/or cardioversion/defibrillation therapy. In another example, the LPD may be configured to deliver post-shock pacing after detecting delivery of anti-tachyarrhythmia shock therapy.

Abstract: An extra-cardiovascular implantable cardioverter defibrillator (ICD) system receives a cardiac electrical signal by an electrical sensing circuit via an extra-cardiovascular sensing electrode vector and senses cardiac events from the cardiac electrical signal. The ICD system detects tachycardia from the cardiac electrical signal and determines a tachycardia cycle length from the cardiac electrical signal. The ICD system determines an ATP interval based on the tachycardia cycle length and sets an extended ATP interval that is longer than the ATP interval. The ICD delivers ATP pulses to a patient's heart via an extra-cardiovascular pacing electrode vector different than the sensing electrode vector. The ATP pulses include a leading ATP pulse delivered at the extended ATP interval after a cardiac event is sensed from the cardiac electrical signal and a second ATP pulse delivered at the ATP interval following the leading ATP pulse.

Abstract: A medical device is configured to determine time intervals between consecutive cardiac events sensed from a cardiac electrical signal, increase a value of a tachyarrhythmia interval count in response to each of the determine time intervals detected as a tachyarrhythmia interval. The device is further configured to detect normal sinus rhythm events and the decrease the value of the tachyarrhythmia interval count in response to a threshold number of detected normal sinus rhythm events.

Abstract: Ventricle-from-atrium (VfA) devices, systems, and methods may be configured to monitor a single channel of cardiac electrical activity and determine atrial events and ventricular events based on the single channel of cardiac electrical activity. Various processing, windowing, and thresholding may be used to identify atrial events and ventricular events within the single channel of cardiac electrical activity.

Abstract: A lower pacing rate limit is utilized by pacing devices to initiate pacing in response to a patient's intrinsic rate being less than the lower pacing rate limit. Illustrative systems, devices, and methods may obtain rate modification information related to a patient such as physical characteristics, diagnostic parameters, pathologies, device characteristics of a pacing device implanted in the patient, and patient-reported information. The rate modification information may be used to determine lower pacing rate limit based thereon.

Abstract: A medical device is configured to determine time intervals between consecutive cardiac events sensed from a cardiac electrical signal, increase a value of a tachyarrhythmia interval count in response to each of the determine time intervals detected as a tachyarrhythmia interval. The device is further configured to detect normal sinus rhythm events and the decrease the value of the tachyarrhythmia interval count in response to a threshold number of detected normal sinus rhythm events.

Abstract: An example medical device system includes memory configured to store information relating to an occurrence of a cardiac event in a patient and processing circuitry configured to determine the occurrence of the cardiac event in the patient. The processing circuitry is configured to determine at least one of a fall of the patient, a slumping posture of the patient, or a change from an upright posture to a non-upright posture of the patient and that the cardiac event is associated therewith in time. The processing circuitry is configured to, in response to determining that the cardiac event and the at least one of the fall of the patient, the slumping posture of the patient, or the change from the upright posture to the non-upright posture of the patient are associated in time, modulate a response to the cardiac event.

Abstract: An implantable medical device system is configured to detect a tachyarrhythmia from a cardiac electrical signal and start an ATP therapy delay period. The implantable medical device determines whether the cardiac electrical signal received during the ATP therapy delay period satisfies ATP delivery criteria. A therapy delivery module is controlled to cancel the delayed ATP therapy if the ATP delivery criteria are not met and deliver the delayed ATP therapy if the ATP delivery criteria are met.

Abstract: An extra-cardiovascular implantable cardioverter defibrillator (ICD) system receives a cardiac electrical signal by an electrical sensing circuit via an extra-cardiovascular sensing electrode vector and senses cardiac events from the cardiac electrical signal. The ICD system detects tachycardia from the cardiac electrical signal and determines a tachycardia cycle length from the cardiac electrical signal. The ICD system determines an ATP interval based on the tachycardia cycle length and sets an extended ATP interval that is longer than the ATP interval. The ICD delivers ATP pulses to a patient's heart via an extra-cardiovascular pacing electrode vector different than the sensing electrode vector. The ATP pulses include a leading ATP pulse delivered at the extended ATP interval after a cardiac event is sensed from the cardiac electrical signal and a second ATP pulse delivered at the ATP interval following the leading ATP pulse.

Abstract: Patient activity or inactivity may be determined based, at least in part, on a movement signal representative, or indicative, of movement of a patient. When the patient is determined to be inactive based the movement signal monitored over a moving time window, cardiac remodeling pacing may be delivered to the patient.

Abstract: An implantable medical device includes an electrically conductive first housing, a conductive feedthrough extending through the first housing, electronic circuitry positioned within the first housing, a device electrode, and a second housing. The electronic circuitry is electrically coupled to the first housing and the feedthrough, and senses electrical signals of a patient and/or delivers electrical stimulation therapy to the patient via the first housing and the feedthrough. The device electrode is configured to electrically connect with tissue and/or a fluid at a target site in the patient. A lead connector is configured to connect to a proximal end of an implantable medical lead. The lead connector includes a first connector contact electrically coupled to the feedthrough and a second connector contact electrically coupled to the first housing.

Abstract: A medical device is configured to determine tachyarrhythmia evidence in a cardiac signal segment received from a cardiac electrical signal sensed during a pacing escape interval started to schedule a pending cardiac pacing pulse. The medical device may delay the pending cardiac pacing pulse in response to determining the tachyarrhythmia evidence during the pacing escape interval.