A particular implantable device includes one or more electrode connectors and multiple circuit elements within a housing. The implantable medical device may also include one or more switches, where each switch of the one or more switches is coupled between one or more of the multiple circuit elements and at least one electrode connector of the one or more electrode connectors.

A novel therapeutic biphasic or multiphasic pulse waveform and method are provided. The novel therapeutic biphasic or multiphasic pulse waveform may be used in a defibrillator, or in another medical device that delivers therapeutic electrical stimulation pulses to a patient.

A therapeutic signal delivery system and method that delivers a dynamically adjustable biphasic or multiphasic pulse are provided. The dynamically adjustable biphasic or multiphasic therapeutic pulse may be used for a variety of therapeutic treatments.

A pulse generation system is disclosed. The pulse generation system includes a controller, an output terminal, and a plurality of pulse generator circuits. The controller is configured to cause a driving signal pulse to be transmitted to any selected one or more of the pulse generator circuits, and to cause the driving signal pulse to not be transmitted to any selected one or more other pulse generator circuits. Each of the pulse generator circuits is configured to generate an output voltage pulse at the output terminal in response to the driving signal pulse being transmitted thereto.

An external defibrillator for use in generating a defibrillation waveform is described. The external defibrillator includes a low voltage energy storage module having one or more low voltage ultra-capacitors that store low voltage energy. A pulse transformer converts the low voltage energy to high voltage defibrillation energy and provides the defibrillation energy to a pair of electrodes configured to be applied to a patient. A modulator receives the low voltage energy from the low voltage energy storage module and transfers the low voltage energy to the pulse transformer. The external defibrillator also includes a battery.

High frequency cardiac arrhythmias and fibrillations are terminated by electric field pacing pulses having an order of magnitude less energy than a conventional cardioversion or defibrillation energy. The frequency and number of the pulses are selected based on a frequency analysis of a present high frequency cardiac arrhythmia or fibrillation. The energy of the pulses is selected from 1/400 to of the conventional defibrillation energy, and the amplitude of the electric field pacing pulses are selected such as to activate a multitude of effective pacing sites in the heart tissue per each pacing electrode. The number and locations of the effective pacing sites in the heart tissue are regulated by the amplitude of the electric field pacing pulses, and by an orientation of the electric field of the pulses.

A dynamically adjustable multiphasic pulse system and method are provided. The dynamically adjustable multiphasic pulse system may be used as pulse system for a defibrillator or cardioverter. The dynamically adjustable multiphasic pulse system may include a subsystem that generates a first phase of a pulse, a separate subsystem that generates a second phase of the pulse and a switch element that switches between the subsystem and the separate subsystem to generate a therapeutic pulse having at least one positive phase and at least one negative phase.

A system and method to deliver a therapeutic quantity of energy to a patient. The system includes a capacitor having a rated energy storage capacity substantially equal to the therapeutic quantity of energy, a boost converter coupled with the capacitor and constructed to release energy from the capacitor at a substantially constant current for a time interval, and an H-bridge circuit coupled with the boost converter and constructed to apply the substantially constant current in a biphasic voltage waveform to the patient. The method includes storing a quantity of energy substantially equal to the therapeutic quantity of energy in a capacitor, releasing the quantity of energy at a relatively constant current during a time interval using a boost converter coupled with the capacitor, and delivering a portion of the quantity energy in a direction to the patient using an H-bridge circuit coupled with the boost converter.

A dynamically adjustable biphasic or multiphasic pulse generation system and method are provided. The dynamically adjustable biphasic or multiphasic pulse generator system may be used as a pulse generation system for a defibrillator or other type of electrical stimulation medical device.

This document describes an automated external defibrillator comprising a control configured to switch between a pediatric operating mode and an adult operating mode, wherein each operating mode comprises a mode-specific energy configuration and a mode-specific user configuration; an indicator configured to provide an indication of the operating mode in use during a resuscitation process; one or more processors configured to switch to the mode-specific energy configuration and the mode-specific user configuration upon a change of operating mode between the pediatric operating mode and the adult operating mode such that the automated external defibrillator delivers a defibrillating shock to a patient based on the mode-specific energy configuration; and an interface of the automated external defibrillator provides resuscitation instructions to a user based on the mode-specific user configuration.