A method for extinguishing a cardiac arrhythmia utilizes destructive interference of the passing of the reentry wave tip of an anatomical reentry through a depolarized region created by a relatively low voltage electric field in such a way as to effectively unpin the anatomical reentry. Preferably, the relatively low voltage electric field is defined by at least one unpinning shock(s) that are lower than an expected lower limit of vulnerability as established, for example, by a defibrillation threshold test. By understanding the physics of the electric field distribution between cardiac cells, the method permits the delivery of an electric field sufficient to unpin the core of the anatomical reentry, whether the precise or estimated location of the reentry is known or unknown and without the risk of inducting ventricular fibrillation. A number of embodiments for performing the method are disclosed.

The present invention provides both methods and devices for termination of arrhythmias, such as ventricular or atrial tachyarrhythmias. The device and method involves application of alternating current (AC) for clinically significant durations at selected therapeutic frequencies through the cardiac tissue to a subject experiencing arrhythmia. Methods are also provided to minimize or eliminate pain during defibrillation.

A method, electrical tissue stimulation system, and programmer for providing therapy to a patient are provided. Electrodes are placed adjacent tissue (e.g., spinal cord tissue) of the patient, electrical stimulation energy is delivered from the electrodes to the tissue in accordance with a defined waveform, and a pulse shape of the defined waveform is modified, thereby changing the characteristics of the electrical stimulation energy delivered from the electrode(s) to the tissue. The pulse shape may be modified by selecting one of a plurality of different pulse shape types or by adjusting a time constant of the pulse shape.

Method for truncating and summating shock vector energy between at least two shock vectors in a defibrillator, including the procedures of applying at least two biphasic defibrillating shock vectors simultaneously via at least two electrode sets until a voltage inversion point, terminating at least a first one of the biphasic defibrillating shock vectors at the voltage inversion point, and directing a remaining energy of the first one of the biphasic defibrillating shock vectors to a second phase of at least a second one of the biphasic defibrillating shock vectors.

A subcutaneous device that includes an electronics-containing housing and a clip configured to anchor the device to an internal structural body component of a patient is injected and anchored to the structural body component. An instrument pre-loaded with the device is caused to be inserted through an incision in the patient and advanced to the structural body component. A pushing force is received on the instrument that causes the clip of the device to be pushed onto the structural body component so that the structural body component is located in a sandwiching region between a top portion of the clip and the housing of the device. Force is applied to the structural body component between the top portion of the clip and the housing of the device to anchor the device to the structural body component.

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.

Methods and apparatus for a three-stage ventricular cardioversion and defibrillation therapy that treats ventricular tachycardia and fibrillation at low energy levels. An implantable therapy generator adapted to generate and selectively deliver a three-stage ventricular therapy and at least two leads operably each having at least one electrode adapted to be positioned proximate the ventricle of the patient. The device is programmed to deliver a three-stage therapy via both a far-field configuration and a near-field configuration of the electrodes upon detection of a ventricular arrhythmia. The three-stage therapy includes a first stage for unpinning of one or more singularities associated with the ventricular 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 associated delivered via the near-field configuration of the electrodes.

A wearable, multiphasic cardioverter defibrillator system and method are provided.

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.

An apparatus for terminating or unpinning rotating electric activity in a cardiac tissue analyzes an electric parameter for rotating electric activity in the cardiac tissue, and generates electric pulses in response to the rotating electric activity. The electric pulses are applied as electric field pulses and include a plurality of rotating electric activity synchronization pulses arranged at first intervals and a rotating electric activity termination or unpinning pulse following to the last synchronization pulse at a second interval which is similar to one of the first intervals. A maximum electric field strength caused the synchronization pulses is not more than 82% of a maximum electric field strength caused by the termination or unpinning pulse, and an electric pulse energy delivered to the cardiac tissue by each of the synchronization pulses is not more than 67% of an electric pulse energy delivered by the termination or unpinning pulse.