Abstract: Systems and methods are described for classifying a cardiac rhythm. A cardiac rhythm is classified using a classification process that includes a plurality of cardiac rhythm discriminators. Each rhythm discriminator provides an independent classification of the cardiac rhythm. The classification process is modified if the modification is likely to produce enhanced classification results. The rhythm is reclassified using the modified classification process.

Abstract: An apparatus and method for adjusting the performance of an implanted device based on data including contextual information. Contextual information, including operational and performance data concerning the implanted device as well as the patient with the implanted device, is stored by a portable electronic device. In one embodiment, the portable electronic device is adapted for battery operation and includes a personal digital assistant (PDA). The portable electronic device is adapted for use as an interface to conduct wireless communications with the implanted device. In one embodiment, the portable electronic device interfaces with a clinical programmer for use by a physician.

Abstract: Described herein are methods and systems for delivering pacing therapy to HF patients who do not exhibit a reduced EF. Such patients do not have systolic dysfunction and generally do not benefit from established HF therapies that either augment contractile function or counteract conduction abnormalities. In one embodiment, a HF patient with a normal EF is tested for the adequacy of heart rate response during exercise. If the patient is found to be chronotropically incompetent, a rate-adaptive pacing mode is employed in order to improve functional capacity.

Abstract: Systems and methods are described for classifying a cardiac rhythm. A cardiac rhythm is classified using a classification process that includes a plurality of cardiac rhythm discriminators. Each rhythm discriminator provides an independent classification of the cardiac rhythm. The classification process is modified if the modification is likely to produce enhanced classification results. The rhythm is reclassified using the modified classification process.

Abstract: A cardiac pacing system preventing short-long-short pacing sequences. The system providing pacing pulses where necessary. The system having dynamic event window generation to adapt to changes in heart rate. The event window adaptable to process a number of intervals. The system including provisions for other inputs, such as sensor and morphology detection. The system adaptable for single mode and dual mode applications. The system also applicable to long pause prevention in atrial pacing and ventricular pacing.

Abstract: An apparatus and method for adjusting the performance of an implanted device based on data including contextual information. Contextual information, including operational and performance data concerning the implanted device as well as the patient with the implanted device, is stored by a portable electronic device. In one embodiment, the portable electronic device is adapted for battery operation and includes a personal digital assistant (PDA). The portable electronic device is adapted for use as an interface to conduct wireless communications with the implanted device. In one embodiment, the portable electronic device interfaces with a clinical programmer for use by a physician.

Abstract: A cardiac pacing system preventing short-long-short pacing sequences. The system providing pacing pulses where necessary. The system having dynamic event window generation to adapt to changes in heart rate. The event window adaptable to process a number of intervals. The system including provisions for other inputs, such as sensor and morphology detection. The system adaptable for single mode and dual mode applications. The system also applicable to long pause prevention in atrial pacing and ventricular pacing.

Abstract: Different types of cardiac arrhythmia are classified based on the morphology of the arrhythmic beats. Cardiac beats associated with an arrhythmic episode are compared to a plurality of representative beat morphologies, each representative beat morphology characterizing a type of arrhythmia of the heart. An arrhythmic episode may be classified as a particular type of arrhythmia if the morphology of the arrhythmic cardiac beats matches a representative beat morphology characterizing the particular type of arrhythmia. An appropriate therapy for the particular type of arrhythmia may be selected based on the arrhythmia classification. A particular type of arrhythmia may be associated with one or more therapies used to treat the arrhythmia. The therapy used to treat the arrhythmia may comprise a therapy identified as a previously successful therapy.

Abstract: Systems and methods provide for sensing of cardiac activity from a subcutaneous, non-intrathoracic location, and detecting a cardiac condition necessitating treatment in response to the sensed cardiac activity. One of a number of cardiac therapies may be selectively delivered to treat the detected cardiac condition, such cardiac therapies including at least a tachycardia therapy, a bradycardia therapy, and an asystole prevention therapy.

Abstract: Disclosed herein, among other things, is system for thermal neuroinhibition. According to an embodiment, the system includes at least one implantable fluid-filled conduit adapted to be placed adjacent to a neural target. The system also includes an implantable housing including a power source, a heat pump deriving power from the source and connected to the conduit, and a controller within the housing. The controller is connected to the heat pump, and is adapted to control the heat pump to effect fluid flow in the conduit to cool the neural target using electromechanical refrigeration to reversibly inhibit neural activity as part of a medical treatment.

Abstract: A cardiac rhythm management device is configured to discriminate between ventricular and supraventricular tachycardias (referred to as SVT/VT discrimination) by utilizing a morphology criterion in which the morphology of electrogram waveforms during ventricular beats are analyzed to determine if the beats are normally conducted. After the delivery of a cardioversion/defibrillation shock, however, the intraventricular conduction system is left in a modified state which alters the subsequently generated electrogram signal. Use of the morphology criterion for SVT/VT discrimination is discontinued after delivery of such a shock and resumed after a predetermined minimum number of normally conducted ventricular beats has been detected.

Abstract: A system and method for discriminating cardiac rhythms in sensed cardiac complexes associated with at least two cardiac signals, which includes at least two electrodes disposed at different locations in a heart for sensing at least two cardiac signals. A controller through a sensing circuit receives the sensed at least two cardiac signals from the electrodes and processes the sensed at least two cardiac signals to compute interelectrode time differences between the cardiac complexes associated with one of the at least two sensed cardiac signals, and corresponding cardiac complexes associated with the other of the at least two sensed cardiac signals. The controller further computes a detection time difference variability from the computed interelectrode detection time difference variabilities.

Abstract: A cardiac rhythm management device is configured to discriminate between ventricular and supraventricular tachycardias (referred to as SVT/VT discrimination) by utilizing a morphology criterion in which the morphology of electrogram waveforms during ventricular beats are analyzed to determine if the beats are normally conducted. After the delivery of a cardioversion/defibrillation shock, however, the intraventricular conduction system is left in a modified state which alters the subsequently generated electrogram signal. Use of the morphology criterion for SVT/VT discrimination is discontinued after delivery of such a shock and resumed after a predetermined minimum number of normally conducted ventricular beats has been detected.

Abstract: A delivery system and method for delivering a right ventricular lead into a right ventricle includes a delivery device having an inflatable balloon at a distal end. The device is inserted into the venous system, the balloon is inflated and the device is floated along a blood flow path within the venous system through the heart and into the pulmonary artery. The lead is delivered into the right ventricle using the device. In one embodiment, the device is a catheter that facilitates placement of a guide wire into the right ventricle for delivery of the lead. The catheter is then removed and the lead is inserted into the right ventricle over the guide wire.

Abstract: A method and apparatus for implementing a signal morphology preservation smoothing scheme. The smoothing scheme includes generating an output signal representative of a filtered version of the input signal, wherein the output signal is generated by adaptively removing low amplitude, high frequency noise components while simultaneously preserving signal morphology of the input signal. The smoothing scheme includes comparison of a distance metric against a distance threshold to determine whether an initial smoothed version of the input signal would be oversmoothed or undersmoothed. Then the smoothing scheme appropriately increments, decrements, or maintains the initial level of smoothing to generate an optimal smoothed signal representative of the output signal.

Abstract: A method for curvature based complex identification and classification comprises sensing a cardiac signal and computing curvatures at sample points on the sensed cardiac signal. Then to extract features from the computed curvatures, and compare the extracted features with a set of predetermined templates, and then to classify the sensed cardiac signal based on the outcome of the comparison.

Abstract: A rate smoothing function used in implantable pulse generators uses detected triggering events, which cause the rate smoothing function to be activated or deactivated, and detected parameter adjusting events, which cause parameter(s) of the rate smoothing function to be changed. In one example, the activation/deactivation and/or change to the parameters of the rate smoothing function are temporary, and the pre-event state of the rate smoothing function is set to a post-adjusting state, such as after a first time interval. Rate smoothing may be selected, activated or deactivated, or adjusted based on a cardiac signal state, or based on an activity or other physiological sensor signal. The adjusted rate smoothing parameters may include an up-smoothing percentage to limit a speed of pacing rate increase and a down-smoothing percentage to limit a speed of pacing rate drop.

Abstract: An implantable cardioverter/defibrillator includes a tachycardia detection system that detects one-to-one (1:1) tachycardia, which is a tachycardia with a one-to-one relationship between atrial and ventricular contractions. When the 1:1 tachycardia is detected, the system discriminates ventricular tachycardia (VT) from supraventricular tachycardia (SVT) based on analysis of a cardiac time interval. Examples of the cardiac time interval include an atrioventricular interval (AVI) and a ventriculoatrial interval (VAI). A template time interval is created during a known normal sinus rhythm. The system measures a tachycardia time interval after detecting the 1:1 tachycardia, and indicates a VT detection if the tachycardia time interval differs from the template time interval by at least a predetermined percentage of the template time interval.

Abstract: A cardiac rhythm management system including a highly sensitive technique for discriminating AF from AFL. An electrode disposed in or about a heart senses a cardiac signal. A controller through a sensing circuit receives the sensed cardiac signal from the electrode and processes the sensed cardiac signal to compute an average cycle length-to-cycle length variation based on serial interval relationships from the sensed cardiac signal, and then comparing the computed average cycle length-to-cycle length variation to one or more pre-determined threshold values to discriminate AF from AFL. As a result of substantial difference in cycle length-to-cycle length variation between AF and AFL (despite similar average cycle lengths), the sequence-based measure of cycle length-to-cycle length variability proves to be a highly specific and reliable discriminator of AF from AFL.

Abstract: An algorithm for detection of tachycardias and for discriminating between supraventricular tachycardia (SVT) and ventricular tachycardia (VT) when a 1:1 tachycardia condition is present that can be implemented in an implantable cardiac rhythm management device. Variability measures of AV and VA intervals during the tachycardia are computed and used to distinguish between SVT and VT.