A spinal cord stimulation (SCS) system includes multiple electrodes, multiple, independently programmable, stimulation channels within an implantable pulse generator (IPG) which channels can provide concurrent, but unique stimulation fields, permitting virtual electrodes to be realized. The SCS system includes a replenishable power source (e.g., rechargeable battery), that may be recharged using transcutaneous power transmissions between antenna coil pairs. An external charger unit, having its own rechargeable battery can be used to charge the IPG replenishable power source. A real-time clock can provide an auto-run schedule for daily stimulation. An included bi-directional telemetry link in the system informs the patient or clinician the status of the system, including the state of charge of the IPG battery. Other processing circuitry in the IPG allows electrode impedance measurements to be made. Further circuitry in the external battery charger can provide alignment detection for the coil pairs.

Rechargeable spinal cord stimulator system

A system for monitoring and/or affecting parameters of a patient's body and more particularly to such a system comprised of a system control unit (SCU) and one or more other devices, preferably battery-powered, implanted in the patient's body, i.e., within the envelope defined by the patient's skin. Each such implanted device is configured to be monitored and/or controlled by the SCU via a wireless communication channel. In accordance with the invention, the SCU comprises a programmable unit capable of (1) transmitting commands to at least some of a plurality of implanted devices and (2) receiving data signal from at least some of those implanted devices. In accordance with a preferred embodiment, the system operates in closed loop fashion whereby the commands transmitted by the SCU are dependent, in part, on the content of the data signals received by the SCU. In accordance with the invention, a preferred SCU is similarly implemented as a device capable of being implanted beneath a patient's skin, preferably having an axial dimension of less than 60 mm and a lateral dimension of less than 6 mm. Wireless communication between the SCU and the implanted devices is preferably implemented via a modulated sound signal, AC magnetic field, RF signal, or electric conduction.

System of implantable devices for monitoring and/or affecting body parameters

This invention is a circumferential ablation device assembly which is adapted to forming a circumferential conduction block in a pulmonary vein. The assembly includes a circumferential ablation element which is adapted to ablate a circumferential region of tissue along a pulmonary vein wall which circumscribes the pulmonary vein lumen, thereby transecting the electrical conductivity of the pulmonary vein against conduction along its longitudinal axis and into the left atrium. The circumferential ablation element includes an expandable member with a working length that is adjustable from a radially collapsed position to a radially expanded position. An equatorial band circumscribes the outer surface of the working length and is adapted to ablate tissue adjacent thereto when actuated by an ablation actuator. The equatorial band has a length relative to the longitudinal axis of the expandable member that is narrow relative to the working length, and is also substantially shorter than its circumference when the working length is in the radially expanded position. A pattern of insulators may be included over an ablation element which otherwise spans the working length in order to form the equatorial band described. The expandable member is also adapted to conform to the pulmonary vein in the region of its ostium, such as by providing a great deal of radial compliance or by providing a taper along the working length which has a distally reducing outer diameter. A linear ablation element is provided adjacent to the circumferential ablation element in a combination assembly which is adapted for use in a less-invasive “maze”-type procedure in the region of the pulmonary vein ostia in the left ventricle.

Circumferential ablation device assembly

A heart monitoring system for a person includes one or more wireless nodes; and a wearable appliance in communication with the one or more wireless nodes, the appliance monitoring vital signs.

Health monitoring appliance

A health care monitoring system for a person includes one or more wireless nodes forming a wireless mesh network; a wearable appliance having a sound transducer coupled to the wireless transceiver; and a heart attack or stroke attack sensor coupled to the wireless mesh network to communicate patient data over the wireless mesh network to detect a heart attack or a stroke attack.

Mesh network stroke monitoring appliance

A capacitor-discharge implantable cardioverter defibrillator (ICD) has a relatively longer device life of greater that 5 years. The longer life of the ICD is achieved by selecting and arranging the internal components of the ICD to deliver a maximum defibrillation countershock optimized in terms of a minimum physiologically effective current (I pe ), rather than a minimum defibrillation threshold energy (DFT). As a result of the optimization in terms of a minimum effective current I pe , there is a significant decrease in the maximum electrical charge energy (E c ) that must be stored by the capacitor of the ICD to less than about 30 Joules, even though a higher safety margin is provided for by the device. Due to this decrease in the maximum E c , as well as corollary decreases in the effective capacitance value required for the capacitor and the net energy storage required of the battery, the overall displacement volume of the ICD is reduced to the point where subcutaneous implantation of the device in the pectoral region of human patients is practical. The size of the capacitor is reduced because the effective capacitance required can be less than about 125 μF. By optimizing both the charging time and the countershock duration for the smaller maximum E c , the size of the battery is reduced because the total energy storage capacity can be less than about 1.0 Amp-hours. In the preferred embodiment, the charging time for each defibrillation countershock is reduced to less than about 10 seconds and the pulse duration of the countershock is reduced to less than about 6 milliseconds.

Implantable cardioverter defibrillator having a smaller displacement volume

A capacitor-discharge implantable cardioverter defibrillator (ICD) has a relatively smaller mass of less than about 120 grams. The smaller mass of the ICD is achieved by selecting and arranging the internal components of the ICD to deliver a maximum defibrillation countershock optimized in terms of a minimum physiologically effective current (Ipe), rather than a minimum defibrillation threshold energy (DFT). As a result of the optimization in terms of a minimum effective current Ipe, there is a significant decrease in the maximum electrical charge energy (Ec) that must be stored by the capacitor of the ICD to less than about 30 Joules, even though a higher safety margin is provided for by the device. Due to this decrease in the maximum Ec, as well as corollary decreases in the effective capacitance value required for the capacitor and the net energy storage required of the battery, the overall displacement volume of the ICD is reduced to the point where subcutaneous implantation of the device in the pectoral region of human patients is practical. The size of the capacitor is reduced because the effective capacitance required can be less than about 125 μF. By optimizing both the charging time and the countershock duration for the smaller maximum Ec, the size of the battery is reduced because the total energy storage capacity can be less than about 1.0 Amp-hours. In the preferred embodiment, the charging time for each defibrillation countershock is reduced to less than about 10 seconds and the pulse duration of the countershock is reduced to less than about 6 milliseconds.

Implantable cardioverter defibrillator having a smaller mass

A capacitor-discharge implantable cardioverter defibrillator (ICD) has a relatively smaller energy storage capacity of less than about 10 Amp-hours The smaller energy storage capacity of the ICD is achieved by selecting and arranging the internal components of the ICD to deliver a maximum defibrillation countershock optimized in terms of a minimum physiologically effective current (I pe ) rather than a minimum defibrillation threshold energy (DFT) As a result of the optimization in terms of a minimum effective current I pe , there is a significant decrease in the maximum electrical charge energy (E c ) that must be stored by the capacitor of the ICD to less than about 30 Joules, even though a higher safety margin is provided for by the device Due to this decrease in the maximum E c , as well as corollary decreases in the effective capacitance value required for the capacitor and the net energy storage required of the battery, the overall displacement volume of the ICD is reduced to the point where subcutaneous implantation of the device in the pectoral region of human patients is practical The size of the capacitor is reduced because the effective capacitance required can be less than about 125 μF By optimizing both the charging time and the countershock duration for the smaller maximum E c , the size of the battery is reduced because the total energy storage capacity can be less than about 10 Amp-hours In the preferred embodiment, the charging time for each defibrillation countershock is reduced to less than about 10 seconds and the pulse duration of the countershock is reduced to less than about 6 milliseconds

Implantable cardioverter defibrillator having a smaller energy storage capacity

An implantable multichamber cardioversion and defibrillation system is provided with multiple independently controllable and programmable switched electrode discharge pathways. This independently controlled switching arrangement provides for control over the polarity, phase, direction and timing of all cardioversion and defibrillation countershocks, and allows for the varying of subsequent countershocks after an initial countershock. The switching arrangement is, preferably, both programmable prior to implantation of the system and re-programmable after implantation of the system.

Implantable cardioverter defibrillator system having independently controllable electrode discharge pathway

An ICD detection method for sensing the occurrence of an R-wave improves the ability to distinguish R-waves from noise through the use of variable declining sensitivity thresholds. The method includes the consideration of the amplitude of at least the previous most recent R-wave to determine a declining threshold of sensitivity used to recognize a subsequent electrical signal as an R-wave. In the method, the amplitude of the previous R-wave may be classified, based upon amplitude, and based upon the classification, a desirable time constant for the declining threshold of sensitivity is provided as an exponential or reverse exponential decay. Alternatively, a piece wise use of various decay formulas may be combined and used to avoid false recognition of noise as an R-wave.

Theodore P. Adams

Papers

Implantable cardioverter defibrillator having a smaller displacement volume

Implantable cardioverter defibrillator having a smaller mass

Implantable cardioverter defibrillator having a smaller energy storage capacity

Implantable cardioverter defibrillator system having independently controllable electrode discharge pathway

R-wave detection method for implantable cardioverter defibrillators