Abstract: Systems and methods for detecting atrial tachyarrhythmias (AT) such as atrial fibrillation (AF) are disclosed. A medical system can include a cardiac signal sensor circuit to sense a cardiac electrical signal and a heart sound (HS) sensor to sense heart a HS signal A cardiac electrical signal metric, including a cycle length variability or a detection of atrial electrical activity, can be generated from the cardiac electrical signal A HS metric can be generated from the HS signal, including a status of detection of S4 heart sound or a S4 heart sound intensity indicator. The system can include an AT detector circuit that can detect an AT event, such as an AF event, using the cardiac electrical signal metric and the HS metric. The system can additionally classify the detected AT event as an AF or an atrial flutter event.

Abstract: This document discusses, among other things, systems and methods to determine amplitude and morphology variations of a first heart sound over a first number of cardiac cycles, and to calculate an atrial fibrillation metric indicative of an atrial fibrillation episode of the heart using the determined amplitude and morphology variations. The systems and methods can determine a variability score using the determined amplitude and morphology variations, and can calculate the atrial fibrillation metric using the variability score.

Abstract: An interrogation system for a medical device includes a memory storing a diagnostic algorithm, a processor configured to run the diagnostic algorithm, and a communication module configured to facilitate data transfer between the interrogation system and the medical device. The diagnostic algorithm is configured to reach a diagnostic conclusion based on data from the medical device. The diagnostic algorithm is configured to iteratively interrogate the medical device for the data from the medical device until the diagnostic algorithm reaches the diagnostic conclusion, each iterative interrogation requesting additional data as compared to prior iterations. The communication module is configured to receive the additional data from the medical device in response to each iterative interrogation. The diagnostic algorithm is further configured to store an indication of the diagnostic conclusion within the memory.

Abstract: Cardiac activity of the heart can be sensed using, for example, one or more leadless cardiac pacemakers (LCPs) that are implanted in a close proximity to the heart. Sensing cardiac activity by the one or more leadless cardiac pacemakers (LCPs) can help the system in determining an occurrence of cardiac arrhythmia. For treatment purposes, electrical stimulation therapy, for example anti-tachyarrhythmia pacing (ATP) therapy, can be delivered by at least one of the devices of the system. Such therapy can help treat the detected cardiac arrhythmia. In some instances, one of the leadless cardiac pacemakers can instruct one or more of the other devices to assist in providing pacing therapy. In some instances, one of the leadless cardiac pacemakers can instruct one or more of the other devices to temporarily stop providing therapy or to simply shut down while another device provides therapy.

Abstract: Cardiac activity of the heart can be sensed using, for example, one or more leadless cardiac pacemakers (LCPs) that are implanted in a close proximity to the heart. Sensing cardiac activity by the one or more leadless cardiac pacemakers (LCPs) can help the system in determining an occurrence of cardiac arrhythmia. For treatment purposes, electrical stimulation therapy, for example anti-tachyarrhythmia pacing (ATP) therapy, can be delivered by at least one of the devices of the system. Such therapy can help treat the detected cardiac arrhythmia. In some instances, one of the leadless cardiac pacemakers can instruct one or more of the other devices to assist in providing pacing therapy. In some instances, one of the leadless cardiac pacemakers can instruct one or more of the other devices to temporarily stop providing therapy or to simply shut down while another device provides therapy.

Abstract: An apparatus includes a sensing circuit configured to generate a sensed physiological signal representative of cardiac activity of a subject, and an arrhythmia detection circuit. The arrhythmia detection circuit is configured to monitor information corresponding to ventricular depolarization (V-V) intervals using the sensed physiological signal; determine a V-V interval distribution; determine a heart rate density index (HRDI) as a portion of samples of the V-V interval distribution corresponding to a V-V interval occurring most often in the distribution; and generate an indication of atrial fibrillation (AF) using the HRDI.

Abstract: Systems and methods for treating cardiac arrhythmias. One example medical device system for delivering electrical stimulation therapy to a heart of a patient may comprise a leadless cardiac pacemaker (LCP) implanted within a heart of a patient and configured to determine occurrences of cardiac arrhythmias, a medical device configured to determine occurrences of cardiac arrhythmias and to deliver defibrillation shock therapy to the patient, wherein the LCP and the medical device are spaced from one another and communicatively coupled, and wherein after the LCP determines an occurrence of a cardiac arrhythmia, the LCP is configured to modify the defibrillation shock therapy of the medical device.

Abstract: Systems and methods for coordinating treatment of abnormal heart activity using multiple implanted devices within a patient. In one example, abnormal heart activity may be sensed by a medical device system. One of the devices of the system may determine to deliver anti-tachycardia pacing therapy to the heart of the patient, and may communicate an instruction to another of the devices of the medical device system to deliver anti-tachycardia pacing (ATP) therapy to the heart. The receiving medical device may then deliver ATP therapy to the heart of the patient.

Abstract: This document discusses, among other things, systems and methods to determine amplitude and morphology variations of a first heart sound over a first number of cardiac cycles, and to calculate an atrial fibrillation metric indicative of an atrial fibrillation episode of the heart using the determined amplitude and morphology variations. The systems and methods can determine a variability score using the determined amplitude and morphology variations, and can calculate the atrial fibrillation metric using the variability score.

Abstract: Systems and methods for detecting atrial tachyarrhythmias (AT) such as atrial fibrillation (AF) are disclosed. A medical system can include a cardiac signal sensor circuit to sense a cardiac electrical signal and a heart sound (HS) sensor to sense heart a HS signal A cardiac electrical signal metric, including a cycle length variability or a detection of atrial electrical activity, can be generated from the cardiac electrical signal A HS metric can be generated from the HS signal, including a status of detection of S4 heart sound or a S4 heart sound intensity indicator. The system can include an AT detector circuit that can detect an AT event, such as an AF event, using the cardiac electrical signal metric and the HS metric The system can additionally classify the detected AT event as an AF or an atrial flutter event.

Abstract: This document discusses, among other things, systems and methods to determine amplitude and morphology variations of a first heart sound over a first number of cardiac cycles, and to calculate an atrial fibrillation metric indicative of an atrial fibrillation episode of the heart using the determined amplitude and morphology variations. The systems and methods can determine a variability score using the determined amplitude and morphology variations, and can calculate the atrial fibrillation metric using the variability score.

Abstract: Systems and methods for detecting atrial tachyarrhythmias (AT) such as atrial fibrillation (AF) are disclosed. A medical system can include a cardiac signal sensor circuit to sense a cardiac electrical signal and a heart sound (HS) sensor to sense heart a HS signal. A cardiac electrical signal metric, including a cycle length variability or a detection of atrial electrical activity, can be generated from the cardiac electrical signal. A HS metric can be generated from the HS signal, including a status of detection of S4 heart sound or a S4 heart sound intensity indicator. The system can include an AT detector circuit that can detect an AT event, such as an AF event, using the cardiac electrical signal metric and the HS metric. The system can additionally classify the detected AT event as an AF or an atrial flutter event.

Abstract: An apparatus includes a sensing circuit configured to generate a sensed physiological signal representative of cardiac activity of a subject, and an arrhythmia detection circuit. The arrhythmia detection circuit is configured to monitor information corresponding to ventricular depolarization (V-V) intervals using the sensed physiological signal; determine a V-V interval distribution; determine a heart rate density index (HRDI) as a portion of samples of the V-V interval distribution corresponding to a V-V interval occurring most often in the distribution; and generate an indication of atrial fibrillation (AF) using the HRDI.

Abstract: An apparatus includes a sensing circuit configured to generate a sensed physiological signal representative of cardiac activity of a subject, and an arrhythmia detection circuit. The arrhythmia detection circuit is configured to monitor information corresponding to ventricular depolarization (V-V) intervals using the sensed physiological signal; determine a V-V interval distribution; determine a heart rate density index (HRDI) as a portion of samples of the V-V interval distribution corresponding to a V-V interval occurring most often in the distribution; and generate an indication of atrial fibrillation (AF) using the HRDI.

Abstract: Systems and related methods for analyzing data sensed from a device implanted in a patient, such as a cardiac pacing system. The system detects and evaluates electric signals within the patient that share a common event marker. By using algorithms and graphical presentation of the collected signals having common event markers, deviations in signals over time can be identified and evaluated in consideration of taking further action related to the patient and the implanted device. The system can also be used in conjunction with an advanced patient management system that includes a programmer or repeater capable of gathering information from the implanted device and transmitting the data to a host via a communications network for evaluation at a remote location.

Abstract: This document discusses, among other things, systems and methods to determine amplitude and morphology variations of a first heart sound over a first number of cardiac cycles, and to calculate an atrial fibrillation metric indicative of an atrial fibrillation episode of the heart using the determined amplitude and morphology variations. The systems and methods can determine a variability score using the determined amplitude and morphology variations, and can calculate the atrial fibrillation metric using the variability score.

Abstract: An interrogation system for a medical device includes a memory storing a diagnostic algorithm, a processor configured to run the diagnostic algorithm, and a communication module configured to facilitate data transfer between the interrogation system and the medical device. The diagnostic algorithm is configured to reach a diagnostic conclusion based on data from the medical device. The diagnostic algorithm is configured to iteratively interrogate the medical device for the data from the medical device until the diagnostic algorithm reaches the diagnostic conclusion, each iterative interrogation requesting additional data as compared to prior iterations. The communication module is configured to receive the additional data from the medical device in response to each iterative interrogation. The diagnostic algorithm is further configured to store an indication of the diagnostic conclusion within the memory.

Abstract: Devices or methods such as for stimulating excitable tissue or sensing physiologic response or other signals that can use separate fixation mechanism is described. An implantable apparatus can include a modular electrostimulation electrode assembly that can include a first module and a second module that can be end user-attachable to each other and end user-detached from each other. The first module can include an electrostimulation electrode fixation support member that can be laid flat against or otherwise conform to a surface of a heart, and can define a centrally located open portal such as for permitting electrode access to the surface of the heart. The second module can include an electrostimulation electrode that can be inserted through the portal of the fixation support member such as to contact the surface of the heart such as to deliver chronic electrostimulation to the heart.

Abstract: Systems and methods for detecting atrial tachyarrhythmias (AT) such as atrial fibrillation (AF) are disclosed. A medical system can include a cardiac signal sensor circuit to sense a cardiac electrical signal and a heart sound (HS) sensor to sense heart a HS signal. A cardiac electrical signal metric, including a cycle length variability or a detection of atrial electrical activity, can be generated from the cardiac electrical signal. A HS metric can be generated from the HS signal, including a status of detection of S4 heart sound or a S4 heart sound intensity indicator. The system can include an AT detector circuit that can detect an AT event, such as an AF event, using the cardiac electrical signal metric and the HS metric. The system can additionally classify the detected AT event as an AF or an atrial flutter event.

Abstract: Systems and methods for coordinating detection and/or treatment of abnormal heart activity using multiple implanted devices within a patient. In one example, cardiac activity may be sensed by two or more medical device, including a leadless cardiac pacemaker. Cardiac activity sensed by one of the implanted devices may be communicated to another one of the implanted devices. Abnormal heart activity may then be determined based on the cardiac activity of both of the medical device.