Abstract: A system for heart performance characterization and abnormality detection includes an interface for receiving sampled data representing an electrical signal indicating electrical activity of a patient heart over multiple heart beat cycles. A signal processor automatically, decomposes the received sampled data to multiple different subcomponent signals in the time domain. The signal processor associates individual decomposed subcomponents with corresponding different cardiac rotors and determined characteristics of the subcomponents indicating relative significance of the rotors in a cardiac atrial condition. A reproduction device provides data indicating the subcomponent characteristics indicating relative significance of the rotors in a cardiac atrial condition.

Abstract: A method of predicting ventricular arrhythmias includes receiving an electrical signal from a subject's heart for a plurality of heart beats, identifying characteristic intervals and heart beat durations of the electrical signal corresponding to each of the plurality of heart beats to provide a plurality of characteristic intervals with corresponding heart beat durations, representing dynamics of the plurality of characteristic intervals as a function of a plurality of preceding characteristic intervals and durations of corresponding heart beats over a chosen period time, assessing a stability of the function over the chosen period of time, and predicting ventricular arrhythmias based on detected instabilities in the dynamics of the characteristic intervals.

Abstract: Easy to use, cost-effective methods and devices for evaluating and treating stress and thereby disorders caused or exacerbated by stress are provided. More particularly methods and devices for identifying RSA waves during respiration which provide a subject with real-time RSA wave information are provided. These methods and devices also can be used to identify drop points in RSA waves. Such methods and devices provide subjects with the ability to maintain parasympathetic outflow and thereby prevent and/or reduce levels of stress.

Abstract: A method of evaluating an electrophysiological signal is disclosed. A mathematical reconstruction over at least one cycle of the electrophysiological signal is used to identify an abnormal substrate. A non-transitory computer readable medium is also disclosed. The nontransitory computer readable medium has stored thereon instructions for identifying a pathological substrate from a mathematical reconstruction of an electrophysiological signal, which, when executed by a processor, causes the processor to perform steps comprising using a mathematical reconstruction over many cycles of the electrophysiological signal to identify a pathological state. A system for evaluating an electrophysiological signal includes a processor configured to identify a pathological condition from a mathematical reconstruction of the electrophysiological signal. The system also includes a data input coupled to the processor and configured to provide the processor with the electrophysiological signal.

Abstract: Disclosed is an apparatus and method for ambulatory, real-time detection of Atrial Fibrillation (AF) providing an overall accuracy that refers to detection of AF, irrespective of the duration of AF and beat-to-beat classification.

Abstract: A method and a device for classifying cardiac arrhythmia, using an electrocardiogram (ECG) signal, are provided. The method includes receiving the ECG signal representing an electrical activity of a heart of an individual over a period of time, the ECG signal including ECG beats. The method further includes converting each of the ECG beats into symbols. The method further includes identifying an arrhythmia class indicating a type of cardiac arrhythmia associated with the individual from arrhythmia classes indicating respective types of cardiac arrhythmia based on the symbols representing each of the ECG beats.

Abstract: Assessing health condition of an animal under study includes receiving heart rate information of the animal under study and performing heart rate variability (HRV) analysis on the received heart rate information for determining autonomic dynamics of the animal under study with respect to a species of which the animal under study is a member, wherein the HRV analysis relates to time domain HRV data and frequency domain HRV data of the received heart rate information that are evaluated with respect to physiological states and corresponding health condition for the time domain HRV data and frequency domain HRV data for the species of the animal under study.

Abstract: Estimating a frequency of a sampled cardiac rhythm signal and classifying the rhythm. The received signal is sampled and transformed into a curvature series. A lobe in the curvature series corresponds to a characteristic point in the sampled series. Characteristic points are selected based on a time of a lobe in the curvature series and, in one embodiment, an amplitude of the signal at the time of the lobe. A frequency of the sampled series is estimated by autocorrelating a function of the series of the characteristic points. In one embodiment, the function is a time difference function. The rhythm is classified by plotting the timewise proximity of characteristic points derived from an atrial signal with characteristic points derived from a ventricular signal. Regions of the plot are associated with a particular rhythm and the grouping of the data corresponds to the classification.

Abstract: A system and method provide for detecting atrial arrhythmias within an implantable medical device capable of sensing and pacing at least an atrium of a heart. Arrhythmia of the atrium is detected. In response to detecting atrial arrhythmia, delivery of pacing signals to the atrium is inhibited under certain conditions. While delivery of the pacing signals to the atrium is inhibited, the detected arrhythmia of the atrium is confirmed during a period of further evaluation. Delivery of pacing signals to the atrium is enabled upon ceasing of the atrial arrhythmia. Inhibiting delivery of the pacing signals during atrial arrhythmia evaluation advantageously provides for an increase in the rate at which the detected arrhythmia is confirmed.

Abstract: A diagnostic method includes receiving data comprising a series of heartbeat intervals acquired from a patient (22). A first type of computation, selected from a group of computation types consisting of time-domain analysis (82), frequency-domain analysis (84), and nonlinear fractal analysis (86), is applied to the data in order to compute a first measure of heart rate variability (HRV) of the patient. A second type of computation, selected from the group and different from the first type, is applied to the data in order to compute a second measure of the HRV of the patient. At least the first and second measures are combined so as to derive a parameter indicative of a condition of cardiac health of the patient.

Abstract: Disclosed is an arrhythmia-diagnosing method and device for diagnosing arrhythmias, such as fibrillation or tachycardia. The arrhythmia-diagnosing method includes the following steps: measuring (a) the heart characteristic length, and the (b) frequency and (c) conduction velocity of the cardiac electrical wave; and (d) determining the occurrence or absence of an arrhythmia by using the three parameters measured in steps (a) to (c). With this invention, it is possible to predict and diagnose an electrical wave tornado, one of the causes of arrhythmia, by using a non-dimensional parameter, to identify patients at risk of death or brain death due to an arrhythmia and to reduce the mortality of patients suffering from arrhythmias significantly.

Abstract: An acute ischemia monitor is disclosed. The monitor, which includes an analog to digital convertor and a processor that performs beat detection, monitors the time course of a heart signal parameter, namely ST segment deviation, computed from an electrocardiogram. The device stores ST deviation statistics for multiple leads. For each lead, upper and lower ST deviation boundaries are computed. For each lead, current ST deviation values are compared with the statistical values to determine a metric indicative of the degree of abnormality of a current ST deviation value. The metric is equal to the difference between the current ST deviation value and the upper or lower boundary, normalized according to the dispersion of the ST deviation. Metrics from different leads are summed and compared to a threshold to determine whether the combined metric is indicative of a cardiac event.

Abstract: A monitoring system for a person includes one or more wireless nodes; and a wearable patch or bandage appliance secured to the person' skin and in communication with the one or more wireless nodes, wherein the patch or bandage appliance monitors and transmits patient vital signs to the wireless nodes.

Abstract: A method and system for determining the mechanism of cardiac arrhythmia in a patient is disclosed. The method basically entails measuring the impedance of cardiac tissue in a portion of the patient's heart using a catheter during an episode of supraventricular tachycardia to produce an iso-impedance map of that cardiac tissue on a video display and analyzing the pattern of the iso-impedance map to differentiate focal arrhythmia caused by a circumscribed region of focal firing and reentrant arrhythmia caused by a macroreentrant circuit. The method can also be used to identify regions of coherent rapidly conducting tissue e.g., Bachman's bundle or the inferoposterior pathway insertion points, to identify focal “mother rotors” throughout the left atrium that may participate in the generation and maintenance of atrial fibrillation and to identify areas of CAFE (complex atrial/fractionated electrograms) that truly reflect these mother rotors.

Abstract: A medical device and associated method for discriminating cardiac events includes determining whether a cardiac evidence counter is greater than a predetermined detection threshold, determining whether to advance from a current state to a next state in response to the evidence counter being greater than the predetermined detection threshold, determining whether advancing from a previous state to the current state occurred while in one of a low variability mode and a high variability mode during the previous state, and determining whether to advance from the current state to a previous state in response to determining whether advancing from a previous state to the current state occurred while operating in one of a low variability mode and a high variability mode during the previous state.

Abstract: Systems and method for assessing a patient's myocardial electrical stability by pacing a patient's heart using a pacing sequence that includes at least two different types of pacing pulses. The pacing rate used is preferably only slightly above the patient's intrinsic heart rate. A degree of alternans, in a signal (e.g., IEGM or ECG) that is indicative of cardiac activity in response to the pacing sequence, is determined. The degree of alternans can be determined by comparing portions of the signal that are indicative of cardiac activity in response to the first type of pacing pulses to portions of the signal that are indicative of cardiac activity in response to the second type of pacing pulses. The patient's myocardial electrical stability is assessed based on the determined degree of alternans.

Abstract: 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.

Abstract: A computer-implemented method for analyzing a physiological signal includes selecting a first time interval containing a pattern of interest in a recording of the physiological signal. Respective values of a characteristic of the physiological signal are computed in a plurality of time segments within the first time interval. The computed values are concatenated to form a signature of the pattern of interest. A further occurrence of the pattern of interest is identified in the physiological signal during a second time interval by matching the signal in the second time interval to the signature.

Abstract: A device senses cardioelectrical signals using a right atrial (RA) lead, which might include far-field R-waves as well as near-field P-waves. The device concurrently senses events using a proximal electrode of an LV lead, which can sense both P-waves and R-waves as substantially near-field events. Suitable templates are then applied to the signals sensed via the proximal LV electrode to identify the origin of the signals (e.g. atrial vs. ventricular) so as to properly classify the corresponding events sensed in the RA as near-field or far-field events. In this manner, far-field oversensing is conveniently detected.

Abstract: A method of identifying potential driver sites for cardiac arrhythmias includes acquiring a plurality of electrograms from a plurality of locations on at least a portion of a patient's heart. Using the acquired electrograms, at least one electrical activity map is generated. Desirable electrical activity maps include complex fractionated electrogram standard deviation and mean maps, dominant frequency maps, peak-to-peak voltage maps, and activation sequence maps. Using one or more of these maps (e.g., by analyzing one or more electrogram morphological characteristics represented by these maps), at least one potential driver site can be detected.

Abstract: Techniques are provided for use by implantable medical devices for controlling ventricular pacing, particularly during atrial fibrillation. In one example, during a V sense test for use in optimizing ventricular pacing, the implantable device determines relative degrees of variation within antecedent and succedent intervals detected between ventricular events sensed on left ventricular (LV) and right ventricular (RV) sensing channels. Preferred or optimal ventricular pacing delays are then determined, in part, based on a comparison of the relative degrees of variation obtained during the V sense test. In another example, during RV and LV pace tests, the device distinguishes QRS complexes arising due to interventricular conduction from QRS complexes arising due to atrioventricular conduction from the atria, so as to permit the determination of correct paced interventricular conduction delays for the patient. The paced interventricular conduction delays are also used to optimize ventricular pacing.

Abstract: A system and method provide detecting and monitoring cardiac electrophysiological changes by determining differences between a reference signal representing a heartbeat signal and an analysis signal representing another heartbeat signal. A set of signal data consisting of a number of heartbeat signals is acquired as a function of time. Individual heartbeat signals within the set of acquired signals are identified, an individual signal comprising data values representing a plurality of sample points during a single heartbeat. One of the identified individual signals or a derived signal representing an average of a subset of the identified individual signals is selected as an analysis signal. A reference signal is identified. The sample points of the reference signal are aligned with the sample points of the analysis signal. A single value representative of mutual correspondence between the sample points of the reference signal and the corresponding sample points of the analysis signal is calculated.

Abstract: A heart monitor is disclosed. The monitor computes ST segment deviations and stores the results in heart rate based histograms. Periodically, the monitor analyzes the histogram data to determine a median value of ST deviation. Subsequently, beats are excluded from the computation of the time series if their ST deviations both varies too far from the long term median value and varies too far from the then current time series value.

Abstract: Systems and Methods for stratifying relative risks of adverse cardiac events by processing a duration of electrocardiograph recordings generally recorded by a Holter type of device. The duration of electrocardiograph recordings are processed to resolve RR interval related data, QT interval related data, and are fitted to formulas to at least partially establish fitting related measures. The fitting formulas incorporate circadian related periodic factors, and can further incorporate additional processing including utilizing Lissajous analysis techniques, among others.

Abstract: Embodiments of the invention are related to systems and methods for setting parameters of implantable medical devices, amongst other things. In an embodiment, the invention includes a method for programming an implantable medical device including sensing concentrations of a predictive marker such as ET-1 in a patient, selecting programming parameter values based on the sensed concentrations of the predictive marker, and implementing the selected programming parameter values. In an embodiment the invention includes a method for detecting arrhythmia in a patient including sensing concentrations of the predictive marker in a patient, selecting a level of stringency to be used in an arrhythmia detection module based on the sensed concentrations of the predictive marker, sensing electrical signals in the patient, and evaluating the sensed electrical signals for indicia of an arrhythmia using the arrhythmia detection module. Other embodiments are also included herein.

Abstract: High resolution full disclosure ECG data is transferred from a body sensor device to a handheld device via a wireless protocol. The handheld device transfers the full disclosure ECG data via a network to a center for analysis.

Abstract: A computer-assisted method for quantitative characterization and treatment of ventricular fibrillation includes acquiring a time series of a ventricular fibrillation (VF) signal using a probe from a patient experiencing VF, subtracting the mean from the time series of the VF signal, calculating a cumulative VF signal after the mean is subtracted from the time series of the VF signal, segmenting the cumulative VF signal by a plurality of sampling boxes, calculating the root-mean-square of the cumulative VF signal as a function of the sampling box size , extracting an exponent of the root-mean-square of the cumulative VF signal as a function of the sampling box size, applying electrical defibrillation to the patient if the exponent is below a predetermined value, and applying cardiopulmonary resuscitation (CPR) to the patient if the exponent is above a predetermined value.

Abstract: Techniques are provided for detecting and distinguishing stroke and cardiac ischemia based on electrocardiac signals. In one example, the device senses atrial and ventricular signals within the patient along a set of unipolar sensing vectors and identifies certain morphological features within the signals such as PR intervals, ST intervals, QT intervals, T-waves, etc. The device detects changes, if any, within the morphological features such as significant shifts in ST interval elevation or an inversion in T-wave shape, which are indicative of stroke or cardiac ischemia. By selectively comparing changes detected along different unipolar sensing vectors, the device distinguishes or discriminates stroke from cardiac ischemia within the patient. The discrimination may be corroborated using various physiological and hemodynamic parameters. In some examples, the device further identifies the location of the ischemia within the heart.

Abstract: An implantable medical device and associated method classify therapy outcomes and heart rhythms in association with therapy outcome. A therapy success time interval is started in response to delivering an arrhythmia therapy. If normal sinus rhythm is detected after the therapy success time interval expires, the delivered therapy is classified as unsuccessful and the detected arrhythmia is classified as a self-terminating rhythm.

Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to perform arrhythmia discrimination based on activation times. A plurality of different sensing vectors are used to obtain a plurality of IEGMs that collectively enable electrical activations to be detected in the left atrial (LA) chamber, the right atrial (RA) chamber, and at least one ventricular chamber of a patient's heart. For each of a plurality of cardiac cycles, there is a determination, based on the plurality of obtained IEGMs, of an LA activation time, an RA activation time, and a ventricular activation time. Arrhythmia discrimination is then performed based on the determined activation times.

Abstract: A system include circuitry to receive information from a mobile device including ECG data representative of a beating heart, circuitry to analyze the ECG data using at least one pattern to detect a notable finding in the ECG data and circuitry to determine at least one pattern to send to the mobile device, based on the analysis of the ECG data. The system sends the at least one determined pattern to the mobile device.

Abstract: Methods and apparatus for determining a patient specific QT-RR curve. One embodiment of a method in accordance with the technology comprises providing electrophysiological data for a specific patient. The method can further include: (a) determining QT durations and RR values for a plurality of heart beats of the specific patient from the electrophysiological data; (b) ascertaining effective RR intervals for the plurality of heart beats by weight-averaging the RR values according to the equation Effective RRi=C×Effective RRi?1+(1?C)×[RRweighted], where C is a number between 0 and 1, and where RRweighted is based on an observed RRi value and a trend predicted RR value; and (d) finding a value Cf defined by a value of C where a curve fitted to the QT durations and the ascertained effective RR intervals is within a desired standard deviation.

Abstract: Detected changes in atrial activation can be used to discriminate between hemodynamically stable and hemodynamically unstable tachyarrhythmias.

Abstract: Techniques are provided for use by implantable medical devices for controlling ventricular pacing, particularly during atrial fibrillation. In one example, during a V sense test for use in optimizing ventricular pacing, the implantable device determines relative degrees of variation within antecedent and succedent intervals detected between ventricular events sensed on left ventricular (LV) and right ventricular (RV) sensing channels. Preferred or optimal ventricular pacing delays are then determined, in part, based on a comparison of the relative degrees of variation obtained during the V sense test. In another example, during RV and LV pace tests, the device distinguishes QRS complexes arising due to interventricular conduction from QRS complexes arising due to atrioventricular conduction from the atria, so as to permit the determination of correct paced interventricular conduction delays for the patient. The paced interventricular conduction delays are also used to optimize ventricular pacing.

Abstract: A self-improving identification method classifies specimens based on class identifiers. The system stores specimen profiles in a database that is updated with additional specimen profiles and with follow-up data that corrects classification of specimens that were initially incorrectly classified. Algorithms use the updated database to discover new class identifiers, modify thresholds of known class identifiers, and drop unnecessary class identifiers to improve classification of specimens.

Abstract: A method, a system and an arrangement to predict at least one system event and a corresponding computer program and a corresponding machine-readable storage medium are configured so that the event is predictable because of trends in observables over a certain period before the occurrence of the events. The method, system and arrangement can be used in particular for patient-specific monitoring of patho-physiological changes but also in geophysical or abstract units such as population or economic systems in which the deviation from a defined normal condition is predicted.

Abstract: Methods and apparatus are provided for discriminating high rate polymorphic QRS complexes from high rate monomorphic QRS complexes to increase the specificity of detection of polymorphic VT and VF employing wavelet transform signal processing of the QRS complexes are disclosed. Wavelet transforms are applied to the sampled amplitude values of a sequence of QRS complexes to develop wavelet transform coefficient (WTC) data sets. At least selected ones of the WTC data sets are processed and comparisons are made to determine a wavelet match score. A determination is made as a function of the wavelet match scores of the series of successive QRS complexes that characterizes the most recent QRS complex as more or less likely to signify polymorphic VT or VF.

Abstract: A method and a system for detection of an arrhythmia and discrimination between different types of arrhythmia to determine whether to administer an electric shock to the heart, the method comprising monitoring the electrical activity of a beating heart, selecting a number of heart beat intervals that will comprise an analysis segment; determining an instantaneous heart rate for each of the heart beat intervals with the segment; calculating the mean instantaneous heart rate for the segment; determining the variability of the instantaneous heart rates compared to a mean; using a linear combination of the mean and the non-linear value for comparison with a predetermined threshold to discriminate the type of arrhythmia to automatically decide if intervention is indicated.

Abstract: A system determines fractal values, a nonlinear fractal ratio and fractal data patterns in a heart and maps determined fractal values to medical conditions. A system for heart performance characterization and abnormality detection includes an interface for receiving sampled data representing an electrical signal indicating electrical activity of a patient heart over at least one heart beat cycle. A signal processor calculates, a first signal characteristic value comprising a first fractal dimension value derived from the sampled data over at least a portion of a heart beat cycle, a second signal characteristic value representing a computed derivative of the first fractal dimension value and a ratio of the first and second signal characteristic values. A comparator compares the calculated ratio with a threshold value to provide a comparison indicator.

Abstract: The invention relates to a method for determining a pathology in a subject, said method comprising: a) correlating N-N intervals with rate dependent fluctuations of electrocardiographic parameters derived from an electrocardiogram (ECG) of said subject or other recordings reflecting cardiac activity of said subject to derive electrocardiographic parameters correlation values, wherein said pathology is determined based on said correlation values.

Abstract: A system and method for classifying cardiac complexes sensed during a tachycardia episode. A first cardiac signal and a second cardiac signal are sensed, where the first cardiac signal has a voltage. A first cardiac complex and a second cardiac complex of a cardiac cycle are detected in the first and second cardiac signal, respectively. A predetermined alignment feature is identified in the second cardiac complex. A datum is defined, or positioned, at a specified interval from the predetermined alignment feature of the second cardiac complex. Voltage values are then measured from the first cardiac complex at each of two or more measurement intervals from the datum. The voltage values are then compared voltage values measured from NSR cardiac complexes to classify the first cardiac complex is either a ventricular tachycardia complex or a supraventricular tachycardiac complex.

Abstract: The invention disclosed includes a method and apparatus for calculation of T-wave alternas in electrocardiographic (ECG) signals; said method comprises the following method steps: (a) collecting and storing an ECG signal; (b) detecting each heartbeat T-wave in the ECG signal using an automatic detection and segmentation algorithm; (c) classifying said heartbeat T-wave as an even or odd heartbeat T-wave; (d) initializing said method by taking the first even and the first odd heartbeat T-wave as their respective initial average; (e) processing all the heartbeat T-waves in the ECG signal to generate an even heartbeat T-wave weighted average and odd heartbeat T-wave weighted average; and (f) calculating TWA using a distance metric between the even heartbeat weighted average and the odd heartbeat weighted average, said distance metric including curve matching Continuous Dynamic Time Warping (CDTW).

Abstract: A method includes storing an electrogram (EGM) template in a memory. The EGM template includes first and second alignment points at first and second peaks of the EGM template, respectively. The method further includes identifying first and second peaks of a cardiac cycle EGM acquired by a medical device and selecting one of the first and second peaks of the cardiac cycle EGM to align with one of the first and second alignment points based on an order in which the first and second peaks of the cardiac cycle EGM occur. Additionally, the method includes aligning the selected one of the first and second peaks with one of the first and second alignment points and determining an amount of similarity between the cardiac cycle EGM and the EGM template after alignment.

Abstract: A CRM system enhances intracardiac electrogram-based arrhythmia detection using a wireless electrocardiogram (ECG), which is a signal sensed with implantable electrodes and approximating a surface ECG. In one embodiment, an intracardiac electrogram allows for detection of an arrhythmia, and the wireless ECG allows for classification of the detected arrhythmia by locating its origin. In another embodiment, the wireless ECG is sensed as a substitute signal for the intracardiac electrogram when the sensing of the intracardiac electrogram becomes unreliable. In another embodiment, a cardiac signal needed for a particular purpose is selected from one or more intracardiac electrograms and one or more wireless ECGs based on a desirable signal quality. In another embodiment, intracardiac electrogram-based arrhythmia detection and wireless ECG-based arrhythmia detection confirm with each other before indicating a detection of arrhythmia of a certain type.

Abstract: A cardiac-activity based prediction of a rapid drop in a patient's blood pressure during extracorporeal blood treatment is disclosed. A proposed alarm apparatus includes a primary beat morphology analysis unit bank of secondary analysis units and an alarm generating unit. The primary beat morphology analysis unit discriminates heart beats in a received basic electrocardiogram signal, classifies each beat into one out of at least two different beat categories, and associates each segment of the signal with relevant event-type data. The event-type data and the basic electrocardiogram signal together form an enhanced electrocardiogram signal, based upon which the primary beat morphology analysis unit determines whether one or more secondary signal analyses should be performed.

Abstract: A delivery apparatus for accessing the pericardial space of a heart including an elongated body defining a lumen and a piercing member that extends from a distal portion of the elongated body for piercing tissue of the heart. A spring expands from a distal end of the piercing member in response to the distal end of the piercing member passing through the tissue and into the pericardial space. An electrode located on the spring in order to sense signals indicative of a distal end of the spring passing through the tissue and into the pericardial space.

Abstract: Implantable electromedical device or loop recorders or ILRs that solve the problem of very low arrhythmia detection specificities in, i.e., high number of false positives, based on detection and analysis of external noise, specifically muscle noise surrounding the electromedical device. Embodiments generally employ active detection of lead or device movement that induces signal artifacts indicative of external noise. One or more embodiments may detect lead or device movement through use of a piezoelectric transducer, for example located proximally to the device or in the lead of the electromedical.

Abstract: Techniques are described for detecting a condition of a patient using a probability-correlation based model that integrates a plurality of parameters associated with the condition. A medical device that operates in accordance with the techniques obtains a plurality of parameters associated with the condition of the patient. The medical device obtains probabilities that the condition of the patient exists based on each single parameter separately and correlations between each of the parameters and the other ones of the parameters. After obtaining the probabilities and correlations associated with each of the parameters, the medical device determines whether the condition of the patient exists based on the determined probabilities and correlations. Such techniques may be particularly effective for use in distinguishing whether a rhythm of a patient is treatable, e.g., VT or VF, or non-treatable, e.g., SVT.

Abstract: An implantable medical device such as an implantable pacemaker or implantable cardioverter/defibrillator includes a programmable sensing circuit providing for sensing of a signal approximating a surface electrocardiogram (ECG) through implanted electrodes. With various electrode configurations, signals approximating various standard surface ECG signals are acquired without the need for attaching electrodes with cables onto the skin. The various electrode configurations include, but are not limited to, various combinations of intracardiac pacing electrodes, portions of the implantable medical device contacting tissue, and electrodes incorporated onto the surface of the implantable medical device.

Abstract: The type of arrhythmia in a patient's heart can be determined by monitoring the atrial and ventricular rate of the heart; detecting a pathological initial ventricular and/or atrial rate during a first time period; if a pathological initial rate is detected, then administering at least one antiarrhythmic cardioactive drug over a short second time period; detecting the heart's response to the administered drug(s), as by comparing the responsive ventricular and atrial rates with the initial ventricular and atrial rates, respectively, within a third time period; and determining the type of atrial or ventricular arrhythmia from the presence or absence of differences, and the type of differences, between the responsive atrial and ventricular rates compared with the initial atrial and ventricular rates. The invention further involves a related device which includes an implantable cardiac device (10) and a drug delivery device (20).