The subject matter of the present disclosure generally relates to techniques for neuromodulation of lymphatic tissue that include applying one or more energy pulses to a neuron of a subject, e.g., via an electrode positioned to deliver sufficient energy to the neuron, to modulate immune function. For example, an adaptive immune reflex of a subject may be modulated via neuromodulation.

An implantable pulse generator (IPG) is disclosed having a plurality of electrode nodes, each electrode node configured to be coupled to an electrode to provide stimulation pulses to a patient's tissue. The IPG includes a digital-to-analog converter configured to amplify a reference current to a first current specified by first control signals; a first resistance configured to receive the first current, wherein a voltage across the first resistance is held to a reference voltage at a first node; a plurality of branches each comprising a second resistance and configured to produce a branch current, wherein a voltage across each second resistance is held to the reference voltage at second nodes; and a switch matrix configurable to selectively couple any branch current to any of the electrode nodes via the second nodes.

Neuromodulation is used to enhance left ventricular relaxation. An exemplary neuromodulation system includes a therapy element positionable in proximity to at least one nerve fiber, and a stimulator configured to energize the therapy element to delivery therapy to the at least one nerve fiber such that left ventricular relaxation and left ventricular contractility are contemporaneously enhanced.

Passive tissue biasing circuitry in an Implantable Pulse Generator (IPG) is disclosed to facilitate the sensing of neural responses by holding the voltage of the tissue to a common mode voltage (Vcm). The IPG's conductive case electrode, or any other electrode, is passively biased to Vcm using a capacitor, as opposed to actively driving the (case) electrode to a prescribed voltage using a voltage source. Once Vcm is established, voltages accompanying the production of stimulation pulses will be referenced to Vcm, which eases neural response sensing. An amplifier can be used to set a virtual reference voltage and to limit the amount of current that flows to the case during the production of Vcm. In other examples, circuitry can be used to monitor the virtual reference voltage as useful to enabling the sensing the neural responses, and as useful to setting a compliance voltage for the current generation circuitry.

Resistively loaded dielectric biconical antenna apparatuses, including systems and devices, that may be used to transmit very short electrical pulses (e.g., nanosecond, sub-nanosecond, picosecond, etc.) into tissue non-invasively at energy levels sufficient to invoke biological changes in the tissue. These resistively loaded dielectric biconical antenna apparatuses may include a resistor ring reducing internal reflection and reducing energy loss, as well as delivering longer pulses (e.g. microsecond to millisecond) to tissue.

Digital-to-Analog Converter (DAC) circuitry useable in a stimulator device is disclosed. The DAC circuitry produces an output current whose magnitude varies as a function of an amplitude value provided by a digital amplitude bus. The relationship of the output current to the amplitude (Iout(A)) may be linear or non-linear depending on the current-voltage characteristics of a circuit in the DAC that is selected for use. For example, if a resistor is selected, the output current will vary linearly with amplitude; if a p-n diode is selected, the output current will vary exponentially with amplitude. The shape of Iout(A) affects the resolution of the output current, and depending on the circuit selected, can cause the resolution to be constant, or at least more constant, over the dynamic range of the DAC circuitry. The DAC circuitry is further beneficial in its ability to be programmed with a minimum and maximum output current.

A system and method for measuring, monitoring and mitigating EMI interference in an implanted stimulation lead system associated with an IPG. A Kelvin connection scheme operative with a diagnostic circuit is provided for sensing an interference voltage induced at a Kelvin connect electrode of the lead system, wherein the diagnostic circuit is configured to generate one or more control signals for adjusting in substantially real time a common-mode voltage reference provided to supply a biasing voltage to the IPG circuitry.

Systems, devices, and techniques for adjusting electrical stimulation based on a posture state of a patient are described. For example, processing circuitry is configured to control delivery of a first informed stimulation pulse defined by at least a first value of an informed stimulation parameter, control delivery of a control stimulation pulse to a patient, the control stimulation pulse defined by at least a first value of a control stimulation parameter, determine a characteristic value of the ECAP signal elicited from the control stimulation pulse, receive, from a sensor, a posture state signal representing a posture state of the patient, and adjust, based on the characteristic value of the ECAP signal and the posture state signal, the first value of the informed stimulation parameter to a second value of the informed stimulation parameter.

Systems, devices, and techniques for adjusting electrical stimulation based on a posture state of a patient are described. For example, a system may include sensing circuitry configured to sense an ECAP signal and processing circuitry configured to control delivery of the electrical stimulation to a patient according to a first value of a stimulation parameter and determine a characteristic value of the ECAP signal. The processing circuitry may also be configured to receive, from a sensor, a posture state signal representing a posture state of the patient, determine, based on the posture state signal, a gain value for the stimulation parameter, adjust, based on the characteristic value of the ECAP signal and the gain value, the first value of the stimulation parameter to a second value of the stimulation parameter, and control delivery of the electrical stimulation according to the second value of the stimulation parameter.

A method of treating cardiovascular disease in a patient includes generating, by an implantable stimulator configured to be implanted beneath a skin surface of the patient, stimulation sessions at a duty cycle that is less than 0.05 and applying, by the implantable stimulator in accordance with the duty cycle, the stimulation sessions to a tissue location associated with the cardiovascular disease. The duty cycle is a ratio of T3 to T4. Each stimulation session included in the stimulation sessions has a duration of T3 minutes and occurs at a rate of once every T4 minutes. The implantable stimulator is powered by a primary battery located within the implantable stimulator and having an internal impedance greater than 5 ohms.