An apparatus comprises an implantable cardiac signal sensing circuit configured to provide a sensed depolarization signal from a ventricle and a processor. The processor includes a signal analyzer module and a tachyarrhythmia discrimination module. The signal analyzer module is configured to determine a measure of stability of ventricular (V-V) depolarization intervals using the depolarization signal, and determine a rate of change of the measure of stability. The tachyarrhythmia discrimination module is configured to detect an episode of tachyarrhythmia using the depolarization signal, determine whether the detected tachyarrhythmia is indicative of atrial tachyarrhythmia using the determined rate of change, and provide the determination to a user or process.

A system for treating cardiac arrhythmias comprising a generator including: a sensing circuitry configured to evaluate one or more identified signals representative of electrical activity of the heart and detect an arrhythmia, a control circuitry that is configured to control delivery of a therapy in response to the detected arrhythmia, the therapy including a first stage of electrical pulses delivered via at least a first electrode, wherein the first set of electrical pulses is configured to destabilize and/or terminate a reentry associated with the arrhythmia, and a first lead coupled to the generator, wherein the first lead includes the first electrode.

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.

Methods and apparatus for a three-stage atrial cardioversion therapy that treats atrial arrhythmias within pain tolerance thresholds of a patient. An implantable therapy generator adapted to generate and selectively deliver a three-stage atrial cardioversion therapy and at least two leads, each having at least one electrode adapted to be positioned proximate the atrium of the patient. The device is programmed for delivering a three-stage atrial cardioversion therapy via both a far-field configuration and a near-field configuration of the electrodes upon detection of an atrial arrhythmia. The three-stage atrial cardioversion therapy includes a first stage for unpinning of one or more singularities associated with an atrial arrhythmia, a second stage for anti-repinning of the one or more singularities, both of which are delivered via the far-field configuration of the electrodes, and a third stage for extinguishing of the one or more singularities delivered via the near-field configuration of the electrodes.

Systems and methods for treating atrial tachyarrhythmias such as atrial fibrillation (AF) are disclosed. By monitoring a patient's hemodynamic sensor response to a candidate AF therapy, the present systems and methods can be used to determine an individualized AF therapy leading to a desirable hemodynamic outcome. A medical system can include one or more programmable therapy circuits and a hemodynamic sensor circuit. The system includes a therapy selection circuit that automatically programs and sequentially delivers at least a first candidate therapy and a different second candidate therapy. By comparing the values of a hemodynamic parameter in response to or during the first candidate therapy to that in response to or during the second candidate therapy, a desired AF therapy can be determined as the candidate therapy that leads to faster or more significant hemodynamic recovery.

Embodiments of the invention provide methods for the detection and treatment of atrial fibrillation (AF) and related conditions. One embodiment provides a method comprising measuring electrical activity of the heart using electrodes arranged on the heart surface to define an area for detecting aberrant electrical activity (AEA) and then using the measured electrical activity (MEA) to detect foci of AEA causing AF. A pacing signal may then be sent to the foci to prevent AF onset. Atrial wall motion characteristics (WMC) may be sensed using an accelerometer placed on the heart and used with MEA to detect AF. The WMC may be used to monitor effectiveness of the pacing signal in preventing AF and/or returning the heart to normal sinus rhythm (NSR). Also, upon AF detection, a cardioversion signal may be sent to the atria using the electrodes to depolorize an atrial area causing AF and return the heart to NSR.

A wireless electrostimulation system can comprise a wireless energy transmission source, and an implantable cardiovascular wireless electrostimulation node. A receiver circuit comprising an inductive antenna can be configured to capture magnetic energy to generate a tissue electrostimulation. A tissue electrostimulation circuit, coupled to the receiver circuit, can be configured to deliver energy captured by the receiver circuit as a tissue electrostimulation waveform. Delivery of tissue electrostimulation can be initiated by a therapy control unit.

An implantable medical device is configured to determine a first atrial arrhythmia score from ventricular events sensed by a sensing circuit of an implantable medical device and determine a second atrial arrhythmia score from an intraventricular signal comprising atrial mechanical event signals attendant to atrial systole and produced by a sensor of the implantable medical device. An atrial arrhythmia is detected based on the first atrial arrhythmia score and the second atrial arrhythmia score.

A medical device processor is configured to receive a first cardiac electrical signal sensed from a first sensing electrode vector, receive a second cardiac electrical signal sensed from a second sensing electrode vector different than the first sensing electrode vector, and construct a third cardiac electrical signal from the first cardiac electrical signal and the second cardiac electrical signal. In some examples, the system determines sensed cardiac events according to at least one setting of a cardiac event sensing threshold control parameter from at least the third cardiac electrical signal and may determine at least one acceptable setting of a sensing control parameter based on the determined sensed cardiac events. The processor may generate an output representative of the determined sensed cardiac events.

Systems and methods for pacing cardiac conductive tissue are described. An exemplary system includes an electrostimulation circuit that may generate HBP pulses to stimulate patient physiologic conduction pathway, such as a His bundle or a bundle branch. The system includes an arrhythmia detector to detect an atrial tachyarrhythmia (AT) with intermittent ventricular conduction. A control circuit may sense ventricular activation and, in response to the detected AT indication, determine or update a His-bundle pacing (HBP) configuration. The HBP may be recursively updated on a beat-by-beat basis using the sensed ventricular activation. The electrostimulation circuit may deliver HBP according to the determined or adjusted HBP configuration to regularize ventricular rate during AT.