| Patent application number | Description | Published |
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| 20080262558 | PATIENT CHARACTERISTIC BASED ADAPTIVE ANTI-TACHY PACING PROGRAMMING - A system including at least one implantable sensor circuit adapted to produce an electrical sensor signal related to one or more physiologic cardiovascular events of a subject, a therapy circuit configured to provide anti-tachycardia pacing (ATP) therapy, and a controller. The controller includes a tachyarrhythmia detection circuit and an efficacy circuit. The tachyarrhythmia detection circuit is configured to detect a tachyarrhythmia episode in the subject using the electrical sensor signal, and to determine whether the tachyarrhythmia episode is of a type that is treatable with ATP. The efficacy circuit is configured to estimate an efficacy of a currently configured ATP therapy for the subject, and the controller is configured to alter a delivery regimen of the currently configured ATP therapy when the estimated ATP therapy efficacy is deemed insufficient. Other systems and methods are described. | 10-23-2008 |
| 20080281367 | SYSTEM AND METHOD TO DETERMINE HEMODYNAMIC TOLERABILITY - An implantable medical device detects a tachyarrhythmia of a heart. During the detected tachyarrhythmia, the device determines a local myocardial impedance. Using the local myocardial impedance, the device determines whether there is sufficient perfusion to the heart. The device can then either deliver a less aggressive device therapy in response to the detected tachyarrhythmia when there is sufficient perfusion to the heart, or deliver a more aggressive device therapy in response to the detected tachyarrhythmia when there is insufficient perfusion to the heart. The perfusion information can also be used to alter tachyarrhythmia detection or classification. | 11-13-2008 |
| 20090005826 | METHOD AND APPARATUS FOR CARDIAC ARRHYTHMIA CLASSIFICATION USING TEMPLATE BAND-BASED MORPHOLOGY ANALYSIS - An implantable cardioverter/defibrillator (ICD) includes a tachyarrhythmia detection and classification system that classifies tachyarrhythmias based on a morphological analysis of arrhythmic waveforms and a template waveform. Correlation coefficients each computed between morphological features of an arrhythmic waveform and morphological features of the template waveform provide for the basis for classifying the tachyarrhythmia. In one embodiment, a correlation analysis takes into account the uncertainty associated with the production of the template waveform by using a template band that includes confidence intervals. | 01-01-2009 |
| 20090036940 | HYPERTENSION DIAGNOSIS AND THERAPY USING PRESSURE SENSOR - An example relates to a method for sensing a pulmonary artery pressure (PAP) and providing a sensed PAP signal, detecting an abnormal blood pressure (BP) condition using information from the sensed PAP signal, delivering a pacing energy to a heart, and automatically altering at least one pacing characteristic in response to the detected abnormal BP condition. The detecting an abnormal BP condition can include detecting various forms of hypertension or hypotension. The automatically altering the at least one pacing characteristic can include automatically altering at least one of a pacing rate, a pacing waveform, an atriventricular (AV) delay, an interventricular (VV) delay, a pacing mode, or a pacing site. The method can also include delivering vagal nerve stimulation and automatically altering the vagal nerve stimulation in response to the detected abnormal BP condition. The detecting the abnormal BP condition can also include using a sensed auxiliary physiological parameter. | 02-05-2009 |
| 20090043355 | SYSTEM FOR EVALUATING PERFORMANCE OF AN IMPLANTABLE MEDICAL DEVICE - A system evaluates the performance of an implantable medical device, such as by using a remote external server and a user interface and stored historical physiological data of a population of congestive heart failure (CHF) patients. A processor is coupled to a patient data storage device to apply multiple algorithm variations against the same implantable physiological data from the patient to produce corresponding resulting CHF indicators. The user interface includes a display that is configured to display to a user information allowing comparison between the resulting CHF indicators from the multiple algorithm variations. The display also includes a population data selector to permit the user to select physiological data from a population that includes a different set of one or more patients or physiological data collected over a period of time from the patient. This permits optimization of an algorithm parameter or selection of a best performing algorithm. | 02-12-2009 |
| 20090099616 | METHOD AND APPARATUS FOR CONCURRENT ATRIO-VENTRICULAR ANTI-TACHYCARDIA PACING - An implantable medical device delivers anti-tachyarrhythmia therapies including anti-tachycardia pacing (ATP). If a detected tachyarrhythmia is classified as a type suitable for treatment using ATP, the implantable medical device selects one of an atrial ATP (A-ATP) mode, a ventricular ATP (V-ATP) mode, and a concurrent atrio-ventricular ATP (concurrent AV-ATP) mode according to the characteristics of the detected tachyarrhythmia. The concurrent ATP mode is an ATP mode during which the atrial pacing pulses and the ventricular pacing pulses are delivered concurrently. In one embodiment, the concurrent AV-ATP mode includes a synchronized atrio-ventricular ATP (synchronized AV-ATP) mode during which atrial and ventricular pacing pulses are delivered synchronously and an independent atrio-ventricular ATP (independent AV-ATP) mode during which atrial and ventricular pacing pulses are delivered concurrently but timed independently. | 04-16-2009 |
| 20090118630 | METHOD AND APPARATUS FOR CARDIAC ARRHYTHMIA CLASSIFICATION USING SAMPLE ENTROPY - An implantable medical device includes an arrhythmia detection and classification system that classifies an arrhythmia episode based on an irregularity parameter and/or a complexity parameter. The arrhythmia episode is detected from a cardiac signal. The irregularity parameter is indicative of the degree of cycle length irregularity of the cardiac signal and the complexity parameter is indicative of the degree of morphological complexity of the cardiac signal. One example of the irregularity parameter is an irregularity sample entropy, or a parameter related to the irregularity sample entropy, computed to indicate the cycle length irregularity. One example of the complexity parameter is a complexity sample entropy, or a parameter related to the complexity sample entropy, computed to indicate the morphological complexity. In one embodiment, the detected arrhythmia episode is classified using both the irregularity parameter and the complexity parameter. | 05-07-2009 |
| 20090131996 | Tachycardia hemodynamics detection based on cardiac mechanical sensor signal regularity - Systems and methods provide for sensing, within a patient and during an event of tachycardia, a signal indicative of a mechanical response of the patient's heart to the tachycardia. Regularity of the signal relative to a threshold established for the patient is determined. A state of patient hemodynamics during the tachycardia event is determined based at least in part on the regularity of the signal. One or more anti-tachycardia therapies to treat the tachycardia may be selected based at least in part on the determined state of patient hemodynamics. The selected one or more anti-tachycardia therapies may be delivered to treat the tachycardia. | 05-21-2009 |
| 20090131999 | Hemodynamic status assessment during tachycardia - Systems and methods provide for sensing, during an event of tachycardia, hemodynamic signals concurrently from at least two spatially separated locations within a patient, and quantifying a spatial relationship between the hemodynamic signals. Hemodynamic stability or state of the patient during the tachycardia event is determine based at least in part on the quantified spatial relationship. One or more anti-tachycardia therapies to treat the tachycardia may be selected based at least in part on the determined stability or state of patient hemodynamics, and the selected one or more anti-tachycardia therapies may be delivered to treat the tachycardia. The hemodynamic signals may comprise at least two, or a mixed combination, of cardiac impedance signals, cardiac chamber pressure signals, arterial pressure signals, heart sounds; and acceleration signals. | 05-21-2009 |
| 20090204163 | METHODS OF MONITORING HEMODYNAMIC STATUS FOR RHYTHM DISCRIMINATION WITHIN THE HEART - Systems and methods of performing rhythm discrimination within a patient's body using sensed hemodynamic signals are disclosed. The method can include the steps of receiving an electrical activity signal from an electrode located within or near the heart, detecting an event of the heart based on the received electrical activity signal, sensing one or more mechanical measurements using a sensor located within the body, analyzing a mechanical activity signal received from the sensor, and confirming the type of event based on the mechanical and electrical activity signals. The sensor can comprise a single pressure sensor configured to sense both atrial and ventricular activity within the heart. | 08-13-2009 |
| 20090254135 | HIGH-ENERGY ANTI-TACHYCARDIA THERAPY - Embodiments of the invention are related to medical devices and methods for delivery high-energy anti-tachycardia therapy to a subject, amongst other things. In an embodiment, the invention includes a medical device including a controller module configured to administer a plurality of electrical pulses to a patient in response to a detected tachycardia, the electrical pulses comprising an amplitude of greater than 3 Volts and less than 40 Volts, the controller configured to modulate the amplitude of the electrical pulses. In an embodiment, the invention includes a method of treating a tachyarrhythmia including administering a first series of electrical pulses to a patient with an implantable medical device, the electrical pulses including an amplitude of greater than 8 Volts and less than 40 Volts, the first series of electrical pulses having an interval of less than about 600 ms in between individual pulses. Other embodiments are also included herein. | 10-08-2009 |
| 20090254137 | Temperature Based Systems and Methods for Tachycardia Discrimination and Therapy - Embodiments of the invention are related to an implantable medical system, amongst other things. In an embodiment, the invention includes a processor, an electrical sensor, and a temperature sensor. The processor is configured to monitor myocardial electrical activity with input from the electrical sensor; identify myocardial electrical activity indicative of an arrhythmia, measure temperature of blood in the coronary venous system with input from the temperature sensor; determine if the arrhythmia is hemodynamically stable or hemodynamically unstable based on the temperature of blood in the coronary venous system, and initiate high-voltage shock therapy if the arrhythmia is hemodynamically unstable. Other embodiments are also included herein. | 10-08-2009 |
| 20090264716 | HEMODYNAMIC MORPHOLOGICAL ANALYSIS FOR RHYTHM IDENTIFICATION - This document discusses, among other things, an apparatus comprising an implantable hemodynamic sensor circuit that provides a hemodynamic signal representative of mechanical function of a cardiovascular system of a subject and a controller circuit communicatively coupled to the hemodynamic sensor circuit. The controller circuit includes a detection module configured to detect an onset of tachyarrhythmia, a signal analyzer module configured to determine a measure of morphological variability of the hemodynamic signal during the episode of tachyarrhythmia, and a rhythm discrimination module configured to deem whether the tachyarrhythmia episode is indicative of ventricular tachycardia (VT) according to the measure of morphological variability. | 10-22-2009 |
| 20090287068 | CARDIAC SIGNAL DISPLAY AND EVENT DETECTION USING MULTIRESOLUTION Z-SCORE TRANSFORM - A system comprising a medical device including a processor and a Z-score transformation (ZST) module. The system also includes a display in communication with the processor. The processor is adapted to receive sensor data obtained from at least first and second sensors adapted to produce a time-varying physiologic electrical sensor signal. At least one of the first and second sensors is implantable. The ZST module calculates a ZST for the sensor data received from the first sensor and a ZST for the sensor data received from the second sensor. The display is adapted to display the ZSTs in visual correspondence with each other over time. | 11-19-2009 |
| 20090292332 | METHOD AND APPARATUS FOR MORPHOLOGY-BASED ARRHYTHMIA CLASSIFICATION USING CARDIAC AND OTHER PHYSIOLOGICAL SIGNALS - A tachyarrhythmia detection and classification system classifies tachyarrhythmias based on an analysis of morphological features of a cardiac signal enhanced by using one or more physiological parameters indicative of hemodynamic stability and/or activity level. The tachyarrhythmia detection and classification system computes a measure of similarity between an arrhythmic waveform of the cardiac signal a template waveform for that cardiac signal, such as a correlation coefficient representative of the correlation between morphological features of the arrhythmic waveform and morphological features of the template waveform. A detected tachyarrhythmia episode is classified by comparing the measure of similarity to a threshold that is dynamically adjusted using the one or more physiological parameters. | 11-26-2009 |
| 20090306486 | SENSING VECTOR CONFIGURATION IN ICD TO ASSIST ARRHYTHMIA DETECTION AND ANNOTATION - An apparatus comprises an implantable cardiac signal sensing circuit, configured to provide a sensed near-field depolarization signal from a ventricle and to provide a sensed a far-field intrinsic atrial signal using a far-field atrial sensing channel, and a controller circuit communicatively coupled to the cardiac signal sensing circuit. The controller circuit includes a P-wave detection module configured to detect an atrial depolarization in the sensed far-field intrinsic atrial signal and a tachyarrhythmia detection module configured to detect an episode of tachyarrhythmia using the sensed near-field depolarization signal and to determine whether the tachyarrhythmia episode is indicative of supraventricular tachycardia (SVT) using the detected atrial depolarization and the sensed near-field depolarization signal. | 12-10-2009 |
| 20090318985 | METHOD AND APPARATUS FOR CONTROLLING ANTI-TACHYARRHYTHMIA THERAPY USING HEMODYNAMIC TOLERABILITY - A cardiac rhythm management system identifies a relationship between one or more hemodynamic parameters sensed from a patient and levels of hemodynamic tolerability of the patient. The identified relationship allows an implantable medical device to control delivery of anti-tachyarrhythmia therapy using the patient's hemodynamic tolerability during a detected tachyarrhythmia episode, in addition to classifying the detected tachyarrhythmia episode by its type and origin. | 12-24-2009 |
| 20100023082 | INDIVIDUALIZED MORPHOLOGY FEATURE EVALUATION AND SELECTION FOR DISCRIMINATION IN IMPLANTABLE MEDICAL DEVICES - An apparatus comprises an implantable sensor, which provides a plurality of physiologic sensor signals of a subject, and a processor. The processor includes a feature module and a detection module. The feature module is configured to identify a feature in the sensor signals and to determine a measure of quality of the feature in the sensor signals. The detection module is configured to perform a morphology analysis of a subsequent portion of at least one of the sensor signals using the feature when the measure of quality of the feature satisfies a quality measure threshold. | 01-28-2010 |
| 20100036447 | NEURAL STIMULATION FOR ARRHYTHMIA RECOGNITION AND THERAPY - A system and method can sense a tachyarrhythmia, compare the sensed tachyarrhythmia with a ventricular tachyarrhythmia criterion, provide a ventricular tachyarrhythmia therapy when the sensed tachyarrhythmia satisfies the ventricular tachyarrhythmia criterion, provide a neural stimulation when the sensed tachyarrhythmia does not satisfy the ventricular tachyarrhythmia criterion, determine whether the tachyarrhythmia continues during or after the neural stimulation when the tachyarrhythmia is sustained, compare the tachyarrhythmia sensed during or after the neural stimulation with a supraventricular tachyarrhythmia (SVT) criterion, and provide a ventricular tachyarrhythmia therapy when the sensed tachyarrhythmia does not satisfy the SVT criterion. | 02-11-2010 |
| 20100057152 | SUSTAINING VENTRICULAR TACHYCARDIA DETECTION - An apparatus comprises an implantable ventricular depolarization sensing circuit configured to provide a sensed ventricular depolarization signal, a timer circuit configured to provide a ventricular time interval between ventricular depolarizations, and a controller circuit communicatively coupled to the ventricular depolarization sensing circuit and the timer circuit. The controller circuit includes a ventricular tachycardia (VT) detection circuit configured to declare an episode of VT when a number of accelerated beats are detected, calculate a hysteresis VT detection threshold interval, and deem whether the episode of VT persists using the hysteresis VT detection threshold interval. | 03-04-2010 |
| 20100204745 | CROSS-CHANNEL NOISE DETECTOR IN IMPLANTABLE MEDICAL DEVICES - An apparatus comprises a primary cardiac signal sensing circuit to sense a first cardiac signal, a secondary cardiac signal sensing to sense a second cardiac signal, and an arrhythmia detection circuit. The primary sensing circuit includes at least first and second implantable electrodes, and the secondary sensing circuit includes a third implantable electrode to deliver high-energy shock therapy. The arrhythmia detection circuit detects tachyarrhythmia using the primary sensing circuit, determines correspondence between events sensed with the primary sensing circuit and events sensed with the secondary sensing circuit, and deems whether a detected rhythm is indicative of noise or is indicative of an arrhythmia according to the determined correspondence. | 08-12-2010 |
| 20100210923 | DEPLOYABLE SENSOR PLATFORM ON THE LEAD SYSTEM OF AN IMPLANTABLE DEVICE - Systems and methods for deploying a sensor assembly onto a cardiac lead are disclosed. The sensor assembly can include a resilient cuff having one or more sensor modules for sensing physiological parameters within the body. The resilient cuff may have a substantially cylindrical shape having an inner diameter that is smaller than an outer diameter of the lead body onto which the cuff is deployed such that the cuff is retained on the lead body by frictional forces. The sensor assembly may be deployed in conjunction with a new lead to be implanted within a chamber of the patient's heart or a body vessel, or may be deployed onto an existing, implanted lead implanted within the patient's body. | 08-19-2010 |
| 20100268290 | METHOD AND APPARATUS FOR SELECTING AND TIMING ANTI-TACHYARRHYTHMIA PACING USING CARDIAC CYCLE LENGTH STABILITY - An implantable medical device delivers anti-tachyarrhythmia therapies including anti-tachyarrhythmia pacing (ATP). When a tachyarrhythmia episode is detected, the implantable medical device analyzes cardiac cycle length stability to determine whether and/or when to deliver an ATP. In one embodiment, the cardiac cycle length stability is measured by existence of stable ventricular tachyarrhythmia clusters (SVTCs) during the tachyarrhythmia episode. Each SVTC includes at least a specified minimum number of heart beats over which the cardiac cycle lengths meet a stability criterion. | 10-21-2010 |
| 20100274146 | DYNAMIC SELECTION OF ALGORITHMS FOR ARRHYTHMIA DETECTION - An apparatus comprises a first implantable sensor produces a first electrical sensor signal representative of cardiac depolarization events of a heart of a subject, a second implantable sensor that produces a second electrical sensor signal representative of hemodynamic function of the heart, a signal analyzer circuit, and an arrhythmia discrimination circuit. The signal analyzer circuit detects an arrhythmic event from the first sensor signal and calculates hemodynamic stability in response to the arrhythmic event detection using the second sensor signal. The arrhythmia discrimination circuit selects, according to a calculated hemodynamic stability produced by the signal analyzer circuit, an arrhythmia discrimination algorithm from among a plurality of candidate arrhythmia discrimination algorithms that are implementable by the arrhythmia discrimination circuit, classifies the detected arrhythmia using the selected arrhythmia discrimination algorithm, and provides the arrhythmia classification to a user or process. | 10-28-2010 |
| 20100274149 | METHODS FOR DETECTING ATRIAL TACHYARRHYTHMIA IN IMPLANTABLE DEVICES WITHOUT DEDICATED ATRIAL SENSING - An apparatus comprises an implantable cardiac signal sensing circuit configured to provide a sensed depolarization signal from a ventricle and a processor. The processor includes a signal analyzer module and a tachyarrhythmia discrimination module. The signal analyzer module is configured to determine a measure of stability of ventricular (V-V) depolarization intervals using the depolarization signal, and determine a rate of change of the measure of stability. The tachyarrhythmia discrimination module is configured to detect an episode of tachyarrhythmia using the depolarization signal, determine whether the detected tachyarrhythmia is indicative of atrial tachyarrhythmia using the determined rate of change, and provide the determination to a user or process. | 10-28-2010 |
| 20100280401 | ATRIAL ARRHYTHMIA DETECTION AND DISCRIMINATION BASED ON INTRACARDIAC IMPEDANCE - An apparatus comprises an implantable impedance sensing circuit configured to sense an atrial impedance signal when coupled to a plurality of implantable electrodes, and an impedance signal analyzer circuit configured to detect a sudden change in a characteristic of the sensed atrial impedance signal that indicates atrial tachyarrhythmia. The impedance signal analyzer circuit classifies the atrial tachyarrhythmia indication as ST when the detected sudden change satisfies an ST threshold value of the characteristic, classifies the atrial tachyarrhythmia indication as AT when the detected sudden change satisfies an AT threshold value of the characteristic that is different from the ST threshold value, classifies the atrial tachyarrhythmia indication as AF when the detected sudden change satisfies an AF threshold value of the characteristic that is different from the ST and AT amplitude threshold values, and provides a classification of the tachyarrhythmia to a user or process. | 11-04-2010 |
| 20100280841 | Adjudication of Arrhythmia Episode Data Systems and Methods - A system and method for automatically adjudicating arrhythmia episode information is described, and includes an episode database having episode data regarding a plurality of different arrhythmia episodes and an adjudication processor configured to output characterization data characterizing the input episode data. The characterization data includes an arrhythmia classification. The system further includes an episode processor configured to process the characterization data and episode data, provide at least one report on the characterization data related to a plurality of the different arrhythmia episodes, and provide at least one programming recommendation or at least one alert. | 11-04-2010 |
| 20100292761 | AUTOMATED DEVICE PROGRAMMING AT CHANGEOUT - This document discusses, among other things, methods and systems for facilitating automated device programming at changeout. A method comprises receiving, from a first device, physiological data at a temporary storage device; and processing the received physiological data, wherein the processing includes determining if a first signal processing function was used by the first device and substantially offsetting the first signal processing function if the first signal processing function was used by the first device; and processing the resultant physiological data to be compatible with a second device. The method further comprising providing the processed resultant physiological data to the second device. | 11-18-2010 |
| 20100305635 | SYSTEM AND METHOD FOR RHYTHM IDENTIFICATION AND THERAPY DISCRIMINATION USING HEMODYNAMIC STATUS INFORMATION - A system and method for controlling cardiac ventricular tachyarrhythmias by acquiring a pressure signal representative of coronary venous pressure (CVP) from a pressure sensor implanted within a coronary vein of the patient. A CVP index is derived based on the pressure signal. The onset of a ventricular tachyarrhythmia episode is detected based on a cardiac rates signal. The CVP index and the rate signal are monitored and, responsive to the rate signal indicating a sustained tachycardia episode during the episode monitoring period, anti-tachycardia therapy selectively withheld and the episode monitoring period is extended based on the CVP index. | 12-02-2010 |
| 20100305642 | ADAPTIVE EVENT STORAGE IN IMPLANTABLE DEVICE - Monitoring physiological parameter using an implantable physiological monitor in order to detect a condition predictive of a possible future pathological episode and collecting additional physiological data associated with the condition predictive of a possible future pathological episode. Monitoring another physiological parameter in order to detect a condition indicative of the beginning of a present pathological episode and collecting additional pathological data in response to the condition. Determining that the condition predictive of a future episode and the condition indicative of a present episode are associated and, in response thereto, storing all the collected physiological data. | 12-02-2010 |
| 20100331905 | METHOD AND APPARATUS FOR CLOSED-LOOP CONTROL OF ANTI-TACHYARRHYTHMIA PACING USING HEMODYNAMIC SENSOR - A cardiac rhythm management (CRM) system includes an implantable medical device that delivers anti-tachyarrhythmia therapies including anti-tachyarrhythmia pacing (ATP) and a hemodynamic sensor that senses a hemodynamic signal. The implantable medical device includes a hemodynamic sensor-controlled closed-loop ATP system that uses the hemodynamic signal for ATP capture verification. When ATP pulses are delivered according to a selected ATP protocol to terminate a tachyarrhythmia episode, the implantable medical device performs the ATP capture verification by detecting an effective cardiac contraction from the hemodynamic signal. The ATP protocol is adjusted using an outcome of the ATP capture verification. | 12-30-2010 |
| 20110071411 | METHOD AND APPARATUS FOR SENSING MECHANICAL ENERGY OF AN IMPLANTABLE LEAD - An apparatus comprises an implantable sensor and a signal analyzer circuit communicatively coupled to the implantable sensor. The implantable sensor is configured for coupling to an implantable lead and the implantable sensor provides an electrical vibration sensor signal representative of mechanical vibration of the implantable lead. The signal analyzer circuit is configured to determine a baseline of the vibration sensor signal, detect a change in the vibration sensor signal from the baseline vibration sensor signal, and provide an indication of the change to a user or process. | 03-24-2011 |
| 20110071413 | MORPHOLOGY BASED ISCHEMIA DETECTION USING INTRACARDIAC ELECTROGRAMS - An apparatus comprises an ambulatory cardiac signal sensing circuit configured to provide an electrical cardiac signal representative of cardiac activity of a subject and processor. The processor includes a feature module, a correlation module, and an ischemia detection module. The feature module is configured to identify a fiducial feature in the cardiac signal and locate one or more cardiac features in the cardiac signal using the fiducial feature. The correlation module is configured to calculate a measure of similarity of morphology for a segment of the cardiac signal that includes the cardiac features. The ischemia detection module is configured to detect a change in the measure of similarity and determine whether the detected change in the measure of similarity is indicative of ischemia. | 03-24-2011 |
| 20110077541 | Methods and Systems for Characterizing Cardiac Signal Morphology Using K-Fit Analysis - A system and method for automatically analyzing a cardiac signal, including the step of providing an episode database on a computer storage medium including a plurality of episode data records of one or more patients. Each episode data record includes a cardiac signal from at least one data-generating device. The method also includes the step of selecting one or more of the N beats to be one or more beat templates, for at least a first cardiac signal having N beats. Another step is determining a value K for the cardiac signal using a computer system where K beat templates can represent all the N beats in the cardiac signal. | 03-31-2011 |
| 20110087301 | IMPLANTABLE DEVICE WITH HEMODYNAMIC SUPPORT OR RESUSCITATION THERAPY - An apparatus comprises an implantable sensor, a stimulation circuit, and a controller. The implantable sensor is configured to provide a sensor signal representative of hemodynamic function of a subject. The stimulation circuit is configured to provide electrical simulation energy to an implantable electrode. The controller is communicatively coupled to the stimulation circuit and the implantable sensor and includes a hemodynamic monitor module. The hemodynamic monitor module is configured to detect an episode of reduced hemodynamic capacity in a subject using the sensor signal. In response to the detected episode, the controller is configured to initiate delivery of the electrical stimulation energy to artificially induce at least one of deep ventilation or rapid ventilation in the subject. The hemodynamic monitor module is configured to obtain a measure of hemodynamic performance after delivery of the electrical stimulation energy. | 04-14-2011 |
| 20110130666 | ENHANCED REPORTING OF PATHOLOGICAL EPISODES - An apparatus comprises a sensor circuit configured to produce a time-varying physiologic sensor signal of a subject and a pathology detection circuit communicatively coupled to the sensor. The pathology detection circuit is configured to detect a first pathological episode using the sensed physiologic sensor signal, deem that the first pathological episode has ended, detect at least one second pathological episode using the sensed physiologic sensor signal, and indicate the first and second pathological episodes as one pathological episode if the first and second episode are detected within a specified time interval. | 06-02-2011 |
| 20110130672 | SELF-ADJUSTING ECG MORPHOLOGICAL FEATURE CORRELATION THRESHOLD - An apparatus comprises first and second sensing circuits, a template generator circuit, and a correlation circuit. The correlation circuit is configured to identify a first fiducial position in a third cardiac signal sensed using the first sensing circuit during a detected rhythm with elevated ventricular rate, align the template correlation features and the correlation features of a fourth cardiac signal using the first fiducial position, calculate a correlation using the correlation features of the template and the correlation features of the fourth cardiac signal, and iteratively searching for a replacement to the first fiducial position in the third cardiac signal according to the calculated correlation. | 06-02-2011 |
| 20110160551 | METHOD AND APPARATUS FOR MORPHOLOGY-BASED ARRHYTHMIA CLASSIFICATION USING CARDIAC AND OTHER PHYSIOLOGICAL SIGNALS - A tachyarrhythmia detection and classification system classifies tachyarrhythmias based on an analysis of morphological features of a cardiac signal enhanced by using one or more physiological parameters indicative of hemodynamic stability and/or activity level. The tachyarrhythmia detection and classification system computes a measure of similarity between an arrhythmic waveform of the cardiac signal, a template waveform for that cardiac signal, such as a correlation coefficient representative of the correlation between morphological features of the arrhythmic waveform and morphological features of the template waveform. A detected tachyarrhythmia episode is classified by comparing the measure of similarity to a threshold that is dynamically adjusted using the one or more physiological parameters. | 06-30-2011 |
| 20110166613 | Automatic Multi-Level Therapy Based on Morphologic Organization of an Arrhythmia - Methods and systems for selecting tachyarrhythmia therapy based on the morphological organization level of the arrhythmia are described. Morphological organization levels of arrhythmias are associated with cardiac therapies. The morphological organization levels are related to cardiac signal morphologies of the arrhythmias. An arrhythmia episode is detected and the morphological organization level of the arrhythmia episode is determined. A cardiac therapy associated with the morphological organization level of the arrhythmia episode is delivered to treat the arrhythmia. For example, the morphological organization levels may be associated with the cardiac therapies based on one or more of retrospective database analysis, patient therapy tolerance, and physician input. The associations may be static or may be dynamically adjusted based on therapy efficacy. | 07-07-2011 |
