Abstract: In an implantable medical device having an electrical lead coupled to tissue of a user and a circuit for measuring the impedance of the lead, a method and apparatus for responding to impedance variations in the lead which includes measuring the impedance of the lead while monitoring physiologic parameters of the user, detecting the presence or absence of electromagnetic interference, and if the impedance of the lead is out-of-range, determining whether the electromagnetic interference exceeds a predetermined value, and if the electromagnetic interference exceeds a predetermined value, administering a therapy to the tissue of the user.

Abstract: A sympatholytic cardiovascular agent delivered by a drug delivery pump to a central nervous system site to alleviate symptoms and otherwise treat heart failure (HF) and pathologies associated with HF. The drug delivery pump can be external or implantable infusion pump (IIP) coupled with a drug infusion catheter extending to the site. A patient activator can command delivery of a dosage and/or an implantable heart monitor (IHM) coupled with a sensor can detect physiologic parameters associated with HF (or pathologies associated with HF) and trigger dosage delivery. The IIP and IHM can be combined into a single implantable medical device (IMD) or can constitute separate IMDs that communicate by any of known communication mechanisms. The sympatholytic cardiovascular agent is one of the group consisting of an alpha-adrenergic agonist and an alpha2-adrenergic agonist, e.g.

Abstract: An extra-systolic stimulation (ESS) therapy addresses cardiac dysfunction including heart failure. ESS therapy employs atrial and/or ventricular extra-systoles via pacing-level stimulation to a heart. These extra-systoles must be timed correctly to achieve beneficial effects on myocardial mechanics (efficacy) while maintaining an extremely low level of risk of arrhythmia induction and excellent ICD-like arrhythmia sensing and detection (security). The present invention relates to therapy delivery guidance and options for improved ESS therapy delivery. These methods may be employed individually or in combinations in an external or implantable ESS therapy delivery device.

Abstract: A lead is connected to an integrated circuit in an implantable medical device in a lead bonding region that includes a lead-receiving recessed region. At least a portion of a lead conductor is bonded in the lead-receiving recessed region, making an electrical and mechanical connection to the integrated circuit that is strong and potentially biostable. In some embodiments, a filler material is provided around the recessed portion of the integrated circuit that receives the lead conductor, and a metal coating is provided around an outer surface of the filler material for additional mechanical stability.

Abstract: The present invention provides improved cathodes and methods for producing such cathodes for ultimate use in conjunction with valve metal capacitors. A family of titanium carbide cathodes according to the present invention can be produced so that they inhabit a pre-existing metallic surface such as an inner surface of a titanium casing adjacent but insulated from direct electrical communication from an anode. Foil-type valve metal anodes as well as porous valve metal anodes formed from metallic powders may be used in conjunction with the titanium cathodes of the present invention.

Abstract: A method and apparatus for delivering corrective therapy through hormone regulation is provided. Inhibition of sympathetic fibers by spinal cord stimulation is used to regulate the levels of hormones such as catecholamines, renin, and calcitonin gene-related peptide. The invention utilizes a closed or open loop feedback system in which physiological parameters such as the concentrations of hormones and sympathetic indicators such as heart rate and urine production are monitored and used to determine the appropriate level of neurostimulation.

Abstract: An improved multi-polar feedthrough assembly employs a particular metallic ferrule material for improved dimensional stability during initial fabrication and sustained hermetic operation. In one aspect, the disclosure relates to implantable medical devices (IMDs) including an IMD enclosure fabricated with grade 2 titanium and having a ferrule material fabricated with grade 4 titanium or grade 5 titanium. In one form, the multi-polar feedthrough assembly includes a filtered feedthrough array (e.g., employing capacitive filters coupled to the electrically conductive pins or serpentine conductors of the array). According to another aspect, the improved multi-polar feedthrough assembly incorporates additional pins, thus increasing the footprint of the assembly, and the additional pins provide analog electrical communication between operative circuitry inside an IMD and analog components external to the IMD.

Abstract: Implantable medical devices in embodiments of the invention may include one or more of the following features: (a) a hermetic enclosure, (b) a low-power control circuit located in the enclosure, (c) a high-power output circuit located in the enclosure for delivering an electrical pulse therapy, (d) a power source and circuitry located in the enclosure for powering the low-power control circuit and the high-power output circuit, the power source and circuitry, (e) a first high-rate cell, (f) a second high-rate cell electrically connected in parallel to the low-power control circuit and the high-power output circuit, (g) and at least one resistive load electrically connected between the first high-rate cell and the second high-rate cell, the at least one resistive load having a resistive value to limit, in the event of an internal short in one of the high-rate cells, the rate by which the shorted high-rate cell drains the other high-rate cell.

Abstract: A system and automated method for assessing ventricular synchrony in ambulatory patients is provided including at least one mechanical sensor (e.g., accelerometer, tensiometric sensor, force transducer, and the like) operatively coupled to a first myocardial location in order to measure a wall motion signal of a first chamber, and a second mechanical sensor operatively coupled to a second myocardial location in order to measure a wall motion signal of a second chamber. The wall motion signals are processed in order to identify the time at which a fiducial (e.g., an inflection point, a threshold crossing, a maximum amplitude, etc.) occurs for each respective signal. The temporal separation between the fiducial points on each respective signal is measured as a metric of ventricular synchrony and can be optionally utilized to adjust pacing therapy timing to improve synchrony.

Abstract: The present invention relates to fabrication methods and apparatus for irrigating medical catheters. Such catheters include at least one section of standard thermoplastic catheter tubing coupled to a section of porous tubing (e.g., ePTFE and the like). A source of fluid couples to the porous portion of tubing to dispense diverse fluids. The manufacturing technique overcomes the inability of such porous material to liquefy and/or bond to most available adhesives by creating a mechanical-based coupling. One aspect of the present invention involves pre-treatment of a portion of a porous material such as ePTFE; that is, a “pre-imbibing” process is employed wherein the ePTFE is saturated with a solution of solvent and dissolved thermoplastic resin. After the solution evaporates a resin-based interstitial residue provides suitable structure that fuses to adjacent thermoplastic material during application of heat, such as during thermal bonding.

Abstract: A manufacturing carrier has an insert that can be configured and reconfigured for a wide variety components. The carrier has a frame configured to be transported by a conveyor, an insert and at least one positioner. The insert has pin holes arranged in a matrix. The positioner is carried in a pin hole and configured for locating a component at an x axis position, a y axis position, and a z axis position in relation to the insert. The positioner is moveable from the pin hole configured for a component to another pin hole to reconfigure the insert for another component.

Abstract: During fabrication of an electrical medical lead, a cut end of a stranded wire conductor is subjected to electrical current sufficient to heat and weld the strands together upon discharge of a high voltage between the cut end and a ground metal plate formed of a material of the stranded wire conductor. The discharge of weld energy between the stranded wire cut end and the ground plate induces heat in the wire strands at the stranded wire cut end and the ground plate sufficient to transfer conductive material from the ground plate to fuse the wire strands together. The fusing inhibits unraveling of the wire strands at the fused cut end, whereby the insertion of the stranded wire cable through a lead body lumen and the connection of the fused stranded wire cut end to a further lead component, e.g., a proximal lead connector element or distal electrode, is facilitated.

Abstract: A pacemaker provides multi-chamber pacing with a pacing interval that can be programmed and adapted in response to cardiac output measurements for a given patient. In a typical embodiment, the pacemaker may provide pacing stimuli to both ventricles of a heart. In addition, the invention may include a measurement device that incorporates first and second blood oxygen saturation sensors for deployment in the left and right ventricle. The oxygen saturation sensors provide a differential measurement that can be used to calculate cardiac output in accordance with the Fick method. The oxygen saturation sensors may be carried by a common trans-septal lead that positions one of the sensors proximate the right ventricle and the other sensor proximate the left ventricle. Alternatively, the oxygen saturation sensors may be deployed via separate leads. Whether single or dual leads are used to carry the oxygen saturation sensors, a respective lead may optionally carry electrodes for sensing, pacing, or both.

Abstract: In general, channel occupancy techniques for multi-channel medical device communication are provided. More specifically, techniques are described for maintaining a communication session between an external device and an implantable medical device (IMD) to reduce the potential for conflict with other programmers. A device, such as an external device, includes a transmit module to transmit telemetry signals to an implantable medical device over a communication channel, and a control unit that communicates data to the IMD via the transmit module. The control unit communicates idle messages over the communication channel during gaps within the data communication to the IMD.

Abstract: The present invention outlines structures and methods for delivering a controllable amount of energy to a patient by automatically compensating for the load impedance detected by an implantable-cardioverter defibrillator (ICD). The invention employs high speed, switching power converter technology for the efficient generation of high energy, arbitrary waveforms. Unlike a linear amplifier, switching power converters deliver high-energy waveforms with an efficiency that is independent of the size and amplitude of the desired waveform. An ICD that uses a switching power converter to deliver the desired energy to the patient stores the energy to be delivered in a storage capacitor. The converter then transforms this energy into an arbitrarily shaped output voltage-controlled or current-controlled waveform by switching the storage capacitor in and out of the output circuit at a high rate of speed. Preferably, the waveform comprises a ramp-type waveform.

Abstract: Methods, devices and systems for automatically generating invoices when medical services are provided to a patient are described. Invoices are automatically generated by the system, for example, when monitoring of certain aspects of the performance of an implantable medical device(IMD) implanted within a body of a patient is initiated by the patient or remotely, or when the delivery of a therapy to the patient through the IMD is initiated locally or remotely. The IMD is capable of bi-directional communication with a communication module, a mobile telephone and/or a Personal Data Assistant (PDA) located outside the patient's body.

Abstract: A method and a system for detecting cardiac arrhythmias that includes detecting RR intervals of the patient wherein each RR interval is an interval between two heart beats, and simulating standard probability density histograms of ?RRs by means of a suitable probability distribution calculated through at least one mathematical formulae, wherein ?RR is a difference between two successive RR intervals. Test probability density histograms of ?RRs of the patient are constructed from the detected RR intervals. Finally, the standard and test histograms are compared to detect whether the patient suffers from cardiac arrhythmia. As non limiting examples, the standard probability density histograms of ?RRs are modeled by a mathematical equation selected from the group consisting of: the Lorentzian distribution, the Gaussian distribution, the Student's t-distribution, and a probability distribution including a linear combination of the Lorentzian and Gaussian distribution.

Abstract: In one embodiment, a method includes sensing depolarizations of a heart at a plurality of different locations, and determining a sequence of the sensed depolarizations. The method may further include identifying a tachycardia condition and stimulating the heart at the plurality of locations based on the determined sequence. For example, the method may be implemented by an implantable medical device in order to improve anti-tachycardia pacing (ATP).

Abstract: The present invention relates to the secure delivery of an extra-systolic stimulation (ESS) therapy to treat cardiac dysfunction that employs atrial and/or ventricular extra-systoles via pacing-like stimulation of the heart. These extra-systoles must be timed correctly to achieve beneficial effects on myocardial mechanics (benefit) while maintaining an extremely low level of risk of arrhythmia induction and excellent ICD-like arrhythmia sensing and detection (security). Further experience with ESS has led to improved implementation methods that depend on better blanking, ESS stimulation timing (of an “extra-systolic interval” or ESI), and ESS therapy delivery options and guidance. These methods may be employed individually or in combinations in an external or implantable ESS therapy delivery device.

Abstract: The present invention provides a method and apparatus for assessing ventricular function on a chronic basis using a plurality of electrodes disposed on or about a left ventricle and/or a right ventricle—and optionally, at least one mechanical or metabolic sensor—all operatively electrically coupled to an implantable medical device. The plurality of electrodes are preferably spaced-apart so that at least one electrode is disposed electrical communication with a discrete volume of ventricular tissue. In one embodiment, the discrete volume of tissue is defined by multiple longitudinal and axial planes as known and used in the medical arts.