Abstract: A method of measuring pressure through a septum in a patient's heart is provided. A lead inserted into the right side of a heart is routed through the septum to gain access to the left side of the heart. The lead includes a mounting mechanism that secures the lead to one or both sides of the septal walls. The lead also includes one or more sensors for measuring cardiac pressure on the left side of the heart and, as necessary, the right side of the heart.

Abstract: An implantable medical lead for transmitting electrical signals between an implantable medical device and selected body tissue comprises a lead body having a distal end portion, a proximal end and an electrically insulating, elongated housing connecting the distal end portion and the proximal end. The proximal end of the lead body carries an electrical connector assembly adapted to be electrically connected to the implantable medical device and the distal end portion of the lead body carries at least one electrode electrically coupled to a terminal contact on the connector assembly. The lead comprises at least one surface susceptible during use of the lead to the accumulation of electrostatic charges, the at least one surface having a coating comprising carbon nanotubes.

Abstract: An implantable cardiac stimulation device provides selective atrial pacing upon detection of a premature ventricular complex (PVC). The device comprises a premature ventricular complex detector that detects premature complexes of the heart, and a sensing circuit that senses atrial events. The device further comprises a P wave discriminator that identifies an atrial event sensed by the sensing circuit following detection of a premature ventricular complex as one of a retrograde P wave and a normal sinus P wave, and an atrial pulse generator that delivers an atrial pacing pulse responsive to the discriminator identifying an atrial event sensed by the sensing circuit following detection of a premature ventricular complex as a retrograde P wave.

Abstract: An exemplary method includes use of a multielectrode device that can help position a cardiac stimulation lead to an optimal site in the heart based at least in part on cardiac motion information acquired via the multielectrode device and one or more pairs of current delivery electrodes that establish potential fields (e.g., for use as a coordinate system). An exemplary multielectrode device may be a multielectrode catheter or a multifilar, electrode-bearing guidewire. Various other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: An exemplary method includes selecting a cross-correlation frequency having an associated cross-correlation period, detecting and binning a heart rate in a heart rate bin, detecting and binning an activity state in an activity state bin, repeating the detecting and binning a heart rate and the detecting and binning an activity state during a cross-correlation period, and summing the products a bin count of the heart rate bins and a bin count of the activity state bins to provide a cross-correlation index for the cross-correlation period. Other exemplary algorithms, methods, devices, systems, etc., are also disclosed.

Abstract: An implantable cardiac stimulation device selects an arrhythmia therapy based upon the time of day. The device comprises an arrhythmia detector that detects an accelerated arrhythmia of a heart, and a data circuit that maintains a time record of cardiac cycle lengths developed during detected accelerated arrhythmias. A therapy circuit provides a selected therapy to the heart based upon the maintained time record of cardiac cycle lengths and the time of day.

Abstract: A surface electrocardiogram (EKG) is emulated using signals detected by the internal leads of an implanted device. In one example, the emulation is performed using a technique that concatenates portions of signals sensed using different electrodes, such as by combining far-field ventricular signals sensed in the atria with far-field atrial signals sensed in the ventricles or by combining near-field signals sensed in the atria with near-field signals sensed in the ventricles. In another example, the emulation is performed using a technique that selectively amplifies or attenuates portions of a single signal sensed using a single pair of electrodes, such as by attenuating near-field portions of an atrial unipolar signal relative to far-field portions of the same signal or by attenuating atrial portions of a cross-chamber signal relative to ventricular portions to the same signal.

Abstract: A subcutaneous cardiac stimulation system verifies accelerated arrhythmia detection before delivering accelerated arrhythmia therapy to the heart. The stimulation system includes a verification circuit that verifies detection of the accelerated arrhythmia with each of first and second sense channels utilizing first and second electrode configurations. The therapy circuit delivers the stimulation therapy to the heart if the accelerated arrhythmia detection is verified with each of the first and second electrode configurations. The system also compensates for transient rate changes during the detection of the accelerated arrhythmia.

Abstract: An exemplary method includes delivering biventricular pacing therapy using one or more timing parameters, detecting loss of capture, deciding if fusion exists without adjusting the one or more timing parameters and, based on the deciding, calling for fusion avoidance or calling for a capture threshold search. Various other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: A method of providing cardiac stimulation therapy and a device for providing the therapy. A patient's cardiac activity as well as cyclical respiration is monitored. Cardiac stimulation is provided as indicated as therapeutic intervention for a variety of cardiac arrhythmias according to variable timing parameters. One or more of the timing parameters under which cardiac pacing stimulations are provided is varied or modulated with the cyclical variations in respiration. The one or more timing parameters are generally shortened or elongated in concert with the alternating inspiration/exhalation phases of respiration. In certain implementations, the patient's respiration is inferred from cardiac based physiologic signals. The methods and devices for providing cardiac stimulation therapy more accurately emulate natural healthy physiologic activity.

Abstract: A shielded electrode assembly for nerve sensing is disclosed. The electrode assembly is a flexible and generally tubular structure that can be wrapped around and secured to the outer surface of a nerve so as to establish and maintain electrical contact therewith. The assembly includes an electrically conductive shield with conductive reference electrodes positioned at opposite ends thereof to define an isopotential reference. A sense electrode is placed within the isopotential reference and senses signals either with respect to the isopotential reference or to a sense reference electrode also positioned within the isopotential reference to a sensing device. The isopotential reference provides a region along which nerve activity propagating along the nerve can be sensed with a large attenuation of any external noise which may be present adjacent the sensing region of the nerve. The shielded electrode assembly facilitates direct, long-term nerve sensing with reduced need for filtering or signal processing.

Abstract: An implantable medical device and associated method are provided including a vibratory alert and a vibration-sensitive sensor. Further included is a circuit in communication with the vibratory alert and the vibration-sensitive sensor. Such circuit is adapted for at least reducing an affect of the vibratory alert on the vibration-sensitive sensor.

Abstract: According the present invention, anode foils are encapsulated in separator material so as to insulate them from the metal housing of an electrolytic capacitor. The present invention also provides for enclosed capacitor configurations for use in stacked capacitor configurations. Preferably, heat-sealable polymeric materials are used as separator materials to encapsulate or enclose the anode assemblies and capacitor configurations. The encapsulated anode assemblies and capacitor configurations of the present invention may be used in implantable cardioverter defibrillators.

Abstract: A method of producing a highly etched electrode for a capacitor from a foil is disclosed. The method comprises first applying a composition to the foil to form a plurality of deposits on the foil surface. The method then includes heating the deposits to form micron-sized features and etching the foil. Preferably, the micron-sized features facilitate etching of the foil surface at the location of the micron-sized features. After etching, the foil is optionally further processed in a combination of optional steps such as widening, forming and finishing steps. The controlled application and heating of deposits on the foil surface allows for positional control of tunnel initiation during etching. Thus, the present invention relates to a method of controlling the etching of a foil, such that tunnel initiation density and the location of tunnel initiation is controlled.

Abstract: In fabricating a header assembly of an implantable medical device, one end of a bore contact wire attached to a connector block is keyed with one guiding channel at an upper region of a feedthru adapter and through the adapter to its undersurface. An opposite end is bent into conformance with an orientation channel on the adaptor undersurface. A tip end of a feedthru wire connected to electronic circuitry of the medical device and projecting out of a casing mounting surface is bent for alignment with the orientation channel so end portions of the feedthru wire and bore contact wire are in end to end engagement, then welded together. A plastic header is molded to encapsulate the adapter, connector block, and bore contact wire and, when solidified, has an undersurface for engagement on the casing and an elongated receptacle aligned with a connector block bore to receive the lead.

Abstract: Morphological features within electrical cardiac signals are tracked and feature changes are monitored to detect renal failure. The morphological feature may be an interval between corresponding polarization events such as the interval between QRS-complexes and peaks of corresponding T-waves (QTmax interval); the interval between QRS-complexes and ends of corresponding T-waves (QTend interval); or the interval between P-waves and corresponding QRS-complexes (PR interval). The feature may also be the elevation of a cardiac signal segment between corresponding polarization events, such as QRS-complexes and corresponding T-waves (ST segment); a duration of a polarization event, such as a QRS-complex (QRS width); or an amplitude of a polarization event, such as a T-wave (T-wave amplitude). The change in the feature may comprise a decrease in QTmax intervals, a decrease in QTend intervals, a deviation in ST segment elevation, an increase in QRS width, an increase in PR interval or a deviation in T-wave amplitude.

Abstract: A system is provided for backing up and synchronizing data stored within a set of programmers used for programming implantable cardiac stimulation devices such as pacemakers or implantable cardioverter defibrillators (ICDs). The data from the programmers that is backed up and synchronized includes programmer software, set up and configuration data, programming parameters, patient personal data, implantable device diagnostic data, and patient diagnostic data received from implanted devices. The implanted devices are classified into one or more groups and the programmer backup system merges and synchronizes data received from all programmers within a particular group. In other words, the backup system operates to ensure that each programmer within a particular group shares the same set up and configuration data, programmer software, patient contact data, and device diagnostic information.

Abstract: Techniques are described for detecting and distinguishing among ischemia, hypoglycemia or hyperglycemia based on intracardiac electrogram (IEGM) signals. In one technique, these conditions are detected and distinguished based on an analysis of: the interval between the QRS complex and the peak of a T-wave (QTmax), the interval between the QRS complex and the end of a T-wave (QTend), alone or in combination with a change in ST segment elevation. By exploiting QTmax and QTend in combination with ST segment elevation, changes in ST segment elevation caused by hypo/hyperglycemia can be properly distinguished from changes caused by cardiac ischemia. In another technique, hyperglycemia and hypoglycemia are predicted, detected and/or distinguished from one another based on an analysis of the amplitudes of P-waves, QRS-complexes and T-waves within the IEGM. Appropriate warning signals are delivered and therapy is automatically adjusted.

Abstract: An implantable cardiac stimulation device provides pacing stimulation therapy from within the left ventricle of a heart. The device includes a pulse generator adapted to be coupled to an implantable cardiac stimulation electrode and a power supply that maintains the stimulation electrode at a negative voltage. The electrode may be implanted within the left ventricle by feeding the electrode from the right ventricle through the right ventricular septum and into the left ventricle.

Abstract: An implantable cardiac device is used to measure one or more parameters relating to cardiac activity of a patient's heart, from which diastolic heart failure (“DHF”) may be monitored and/or detected. These parameters are used to calculate ventricular isovolumetric relaxation time or a related time value. Heart conditions possibly having an influence on the ventricular isovolumetric relaxation time, other than heart conditions due to reduced compliance, may be detected and used to prevent an incorrect calculation of the ventricular isovolumetric relaxation time. The parameters may be measured and the relaxation time calculated multiple times over a period of time, which enables monitoring of the progression of change in the relaxation time. The relaxation time and the progression of change therein are indicators of DHF.