Abstract: The invention provides a sleep analysis system and a method for analysis thereof. The sleep analysis system includes an analysis device and a sleep sensing apparatus. The sleep sensing apparatus includes an ECG signal collector, a multi-axial accelerometer, a wireless transmitting unit, and a control unit. The ECG signal collector is used for collecting an ECG signal associated with a subject. The multi-axial accelerometer is used for detecting a multi-axial accelerometer signal associated with the subject. The control unit controls the wireless transmitting unit to transmit the ECG signal and the multi-axial accelerometer signal to the analysis device for analyzing sleep of the subject.

Abstract: Exemplary techniques and systems for interpolating left ventricular pressures are described. One technique interpolates pressures within the left ventricle from blood pressures gathered without directly sensing blood pressure in the left ventricle.

Abstract: Methods and apparatus for utilizing multiple sources of physiologic data to enhance measurement robustness and accuracy. In one embodiment, phonocardiography or “heart sounds” data is used in combination with one or more other techniques (for example, impedance cardiography or ICG waveforms, and/or electrocardiography or ECG waveforms) to provide more accurate and robust physiological and/or hemodynamic assessment of living subjects. In one variant, the aforementioned methods and apparatus are used to improve ICG fiducial point (e.g., B, C and X point) detection and identification accuracy. Moreover, the new ICG fiducial points that may be clinically important may be identified using the disclosed methods and apparatus. In a further aspect, the invention discloses methods and apparatus for utilization of ICG and/or ECG waveform information to improve the identification and characterization of heart sounds (such as e.g., S1, S2, S3, or S4 heart sounds), murmurs, and other such artifacts or phenomena.

Abstract: Techniques are provided for detecting heart failure or other medical conditions within a patient using an implantable medical device, such as pacemaker or implantable cardioverter/defibrillator, or external system. In one example, physiological signals, such as immittance-based signals, are sensed within the patient along a plurality of different vectors, and the amount of independent informational content among the physiological signals of the different vectors is determined. Heart failure is then detected by the implantable device based on a significant increase in the amount of independent informational content among the physiological signals. In response, therapy may be controlled, diagnostic information stored, and/or warning signals generated. In other examples, at least some of these functions are performed by an external system.

Abstract: An implantable medical device includes an integrated or connectable implantable three-dimensional acceleration sensor, and a ballistocardiogram (BCG) capturing unit that is connected or connectable to the acceleration sensor. The BCG evaluation unit processes an acceleration signal provided by the acceleration sensor and derives a BCG from the 3D accelerometer output signal. A BCG evaluation unit is connected to the BCG capturing unit, and is designed to evaluate a BCG provided by the BCG capturing unit and supply an output signal representing stroke volume.

Abstract: A maternal-fetal monitoring system for use during all stages of pregnancy, including antepartum and intrapartum stages. The maternal-fetal monitoring system of the subject invention comprises (1) a set of sensors; (2) an amplifying/filtering means; (3) a computing means; and (4) a graphical user interface. Accurate clinical data, which can be extracted and provided to the user in real-time using the system of the invention, include without limitation, maternal electrocardiogram (ECG) signals, maternal uterine activity signals (EHG), maternal heart rate, fetal ECG signals, and fetal heart rate. In a preferred embodiment, the maternal-fetal monitoring system of the invention includes an intelligence means, such as a neural network system, to analyze and interpret clinical data for use in clinical diagnosis antepartum, intrapartum and postpartum, as well as delivery strategy.

Abstract: Methods and systems are directed to selecting from a variety of capture verification modes. A plurality of capture verification modes, including a beat by beat capture detection mode and a capture threshold testing mode without intervening beat by beat capture detection is provided. An efficacy of at least one of the capture verification modes is evaluated and, based on the evaluation, a capture verification mode is selected.

Abstract: A method comprises monitoring a heart rate, a respiration rate and an activity level of a patient, comparing the monitored heart rate, respiration rate and activity level to a predetermined threshold zone which is a function of heart rate, respiration rate and activity level, determining the patient is experiencing worsening heart failure when the monitored heart rate, respiration rate and activity level are outside the predetermined threshold zone; and after determining the patient is experiencing worsening heart failure when the monitored heart rate, respiration rate and activity level are outside the predetermined threshold zone, issuing an alert to indicate that the patient is experiencing worsening heart failure.

Abstract: Techniques are provided for tracking patient respiration or other physiologic states based upon intracardiac electrogram (IEGM) signals. In one example, respiration patterns are detected based upon cycle-to-cycle changes in morphological features associated with individual cardiac cycles while taking into account different cardiac rhythm types within the patient, such as predominantly paced or predominantly intrinsic rhythm types. Once respiration patterns have been identified, episodes of abnormal respiration, such as apnea, hyperpnea, nocturnal asthma, or the like, may be detected and therapy automatically delivered. In addition, techniques for detecting abnormal respiration using a pattern classifier are described, wherein the pattern classifier is trained while distinguishing the different cardiac rhythm types of the patient.

Abstract: Methods and systems for preventing the underlying anatomical cause that gives rise to a predisposition to SIDS are provided. Methods and systems are provided for the diagnosis of infants predisposed to SIDS. Methods and systems are provided for the therapeutic treatment of infants predisposed to SIDS. A treatment device includes an auditory stimulation system, a monitoring system, a warming system and a response system that can respond to and alleviate crisis situations.

Abstract: A system and method for monitoring an individual's physiological condition and detecting abnormalities therein, comprising concurrently receiving an electrocardiograph signal and a ballistocardiograph signal. The electrocardiograph and ballistocardiograph signals are conditioned to minimize background extraneous noise after which, each signal is concurrently processed and analyzed to detect repeating cyclical patterns and further characterized to identify individual components of the repeating cycles. At least one individual component in one signal is selected as a reference marker or a selected component in the other signal. The two signals are then synchronized, outputs produced therefrom and stored in a database.

Abstract: The invention relates to an intracardial implantable electrode line for connection to an implantable medical device, in particular a cardiac pacemaker or cardioverter/defibrillator or the like, which has an acceleration sensor in the area of its distal end, which is implemented to record and differentiate acceleration values in at least two different directions. The invention additionally relates to a cardiac stimulation configuration which also has a cardiac stimulator in addition to such an electrode line.

Abstract: An apparatus for outputting heart sounds includes an implantable system and an external system. The implantable system includes a sensor for generating sensed signals representing detected heart sounds, an interface circuit and a control circuit for receiving the sensed signals, generating data representing the heart sounds therefrom, and transmitting the data to the external system via the interface circuit. The external system includes an interface circuit for communicating with the implantable system, and a control circuit for receiving the data representing the heart sounds and for generating control signals that cause an output device to generate outputs representing the sounds. The implantable system may also include a sensor(s) for detecting cardiac electrical signals. In this case, outputs representing the cardiac electrical signals are also output.

Abstract: A method of analyzing physiological data indicative of myocardial activity is disclosed. The method comprises: identifying in the data a set of N features, each corresponding to a ventricular depolarization, and calculating M time-intervals for each ventricular depolarization feature, thereby providing a vector of N*M time-intervals. The method further comprises fitting the vector to a power density function of time-intervals, and determining possible cardiac arrhythmia based on statistical parameters characterizing the function.

Abstract: A system and method are provided for determining an index of autonomic nervous system (ANS) or sympathetic nervous system (SNS) activity for use in patient monitoring or therapy delivery control. An ANS or SNS index is calculated as a function of multiple monitored physiological variables that strongly correlate to changes in autonomic or sympathetic tone. These ANS-influenced variables are derived from selected hemodynamic and/or electrical signals and may include variables relating to any of: the maximum rate of pressure rise (dP/dtmax), the maximum rate of pressure decline (dP/dtmin), pulse pressure (PP), pre-ejection time interval (PEI) and/or systolic time interval (STI), heart rate (HR), heart rate variability (HRV), and baro-reflex gain. Changes in the ANS or SNS index may be used to automatically adjust a device delivered therapy.

Abstract: Techniques are provided for detecting stroke within a patient using an implantable medical device in conjunction with an external confirmation system. In one example, a preliminary detection of stroke is performed by a subcutaneous monitor based on an analysis of features of an electrocardiogram (ECG) sensed within the patient. Exemplary ECG features indicative of possible stroke include the onset of prominent U-waves, the onset of notched T-waves, and changes in ST segment duration or QT duration or dynamic trends in these parameters. The monitor transmits a signal indicative of possible stroke to a bedside monitor or other external system, which generates a stroke questionnaire for use in confirming the stroke. Family members or other caregivers input answers to the questionnaire into the external system, which confirms or disconfirms the stroke. Emergency personnel can be automatically notified.

Abstract: In a method and an apparatus for creating hemodynamic sensor signal templates using an implantable medical device connectable to a patient heart activity of the patient is sensed in order to identify a paste or sensed sequence of events of a heart cycle. Hemodynamic sensor signals for consecutive heart cycles are sensed and the sensed hemodynamic sensor signals for consecutive heart cycles are stored. The sensed sensor signals are classified dependent on at least one predetermined heart event sequence condition. A template may be created using the classified sensor signals.

Abstract: Systems and methods using a heart valve and an implantable medical device, such as for event detection and optimization of cardiac output. The cardiac management system includes a heart valve, having a physiological sensor. The physiological sensor is adapted to measure at least one of an intrinsic electrical cardiac parameter, a hemodynamic parameter or the like. The system further includes an implantable electronics unit, such as a cardiac rhythm management unit, coupled to the physiological sensor of the heart valve to receive physiological information. The electronics unit is adapted to use the received physiological information to control delivery of an electrical output to the subject.

Abstract: A biosignal measurement module is provided and includes a biosignal measurement unit, a pose detection unit, and a processing unit. The biosignal measurement unit measures an electrocardiogram signal and a pulse signal of a subject. The pose detection unit detects a position of the biosignal measurement module and outputs position signals. The processing unit receives the electrocardiogram signal, the pulse signal, and the position signals. The processing unit generates a height variation parameter, which indicates the height difference between the position of the biosignal measurement module and a reference position, according to the position signals. The processing unit calculates a current pulse transit time according to the electrocardiogram signal and the pulse signal and compensates for the current pulse transit time according to the height variation parameter to obtain a compensated pulse transit time. The processing unit obtains a blood pressure signal according to the compensated pulse transit time.

Abstract: The invention provides a system for continuously monitoring a patient during hemodialysis. The system includes a hemodialysis machine for performing the hemodialysis process that features a controller, a pump, a dialyzer filter, a lumen, and an interface to a body-worn monitor. A patient attaches to the dialysis machine through the lumen, and wears a body-worn monitor for continuously measuring blood pressure. The monitor includes an optical system for measuring an optical waveform, an electrical system for measuring an electrical waveform, and a processing component for determining a transit time between the optical and electrical waveforms and then calculating a blood pressure value from the transit time. The body-worn monitor features an interface (e.g. a wired serial interface, or a wireless interface) to transmit the blood pressure value to the controller within the hemodialysis machine.

Abstract: A ventricular rate based on first candidate waveforms and second candidate waveforms within sensed ventricular waveforms is compared to an atrial rate. If the ventricular rate exceeds the atrial rate, the first candidate waveforms and second candidate waveforms are compared to a ventricular polarization complex template to obtain a first morphology indicator and a second morphology indicator. If a morphology match inconsistency is present, the amount by which the ventricular rate exceeds the atrial rate is compared to a threshold. If the threshold is exceeded, high-ventricular-rate therapy to the heart is inhibited. The ventricular polarization complex template may be a QRS-complex template, in which case a match inconsistency is present if each of the first candidate waveforms and the second candidate waveforms do not match the QRS-complex template.

Abstract: A system and method for evaluating a patient status from sampled physiometry for use in respiratory insufficiency management and heart failure assessment is presented. Physiological measures are stored and include direct measures regularly recorded on a substantially continuous basis by a medical device for a patient or measures derived from the direct measures. The physiological measures are sampled, which each relate to a same type of physiometry, and those of the physiological measures, which each relate to a different type of physiometry. A status is determined through analysis of those sampled physiological measures assembled from a plurality of recordation points. The sampled physiological measures are evaluated. Any trends are identified and include one of a status quo and a change, which might affect cardiac performance or respiratory performance.

Abstract: An automated patient care system and method for diagnosing and monitoring respiratory insufficiency is presented. A plurality of monitoring sets are stored into a database. Each monitoring set includes recorded measures, which each relate to patient information and contain medical device measures recorded on a substantially continuous basis or derived measures calculable therefrom. The monitoring sets are retrieved from the database. A set of indicator thresholds are defined. Each indicator threshold corresponds to a quantifiable physiological measure of a pathophysiology indicative of respiratory insufficiency. A respiratory insufficiency finding is diagnosed. A change in patient status is determined by comparing at least one recorded measure to at least one other recorded measure with both recorded measures relating to the same type of patient information. Each patient status change is compared to the indicator threshold corresponding to the same type of patient information as the recorded measures.

Abstract: An active implantable medical device for cardiac resynchronization with automatic optimization of atrioventricular and interventricular delays is disclosed. The device collects an endocardial acceleration signal EA and calculates the atrioventricular delay AVD and the interventricular delay VVD. The device isolate in the EA signal a component EA4 corresponding to the fourth EA peak and measure a temporal parameter related to a time interval between the detection of an atrial event (P/A) and the occurrence of the EA4 component. The device isolates an EA1 component corresponding to the first EA peak and measures a non-temporal parameter (APEA1) related to the peak amplitude or a signal energy of the EA1 component. The optimal AVD (AVDO) is determined by the temporal parameter related to the EA4 component, and is calculated for a plurality of different values of VVD to obtain a plurality of pairs of optimal values {AVDO, VVD}.

Abstract: A first lead provides therapeutic stimulation to the heart and includes a first mechanical sensor that measures physical contraction and relaxation of the heart. A controller induces delivery of therapeutic stimulation via the first lead. The controller receives signals from the first mechanical sensor indicative of the contraction and relaxation; develops a template signal that corresponds to the contraction and relaxation; and uses the template signal to modify the delivery of therapeutic stimulations. In another arrangement, a second lead, with a second mechanical sensor also provides signals to the controller indicative of contraction and relaxation. The first mechanical sensor is adapted to be positioned at the interventricular septal region of the heart, and the second mechanical sensor is adapted to be positioned in the lateral region of the left ventricle. The controller processes the signals from the first mechanical sensor and the second mechanical sensor to develop a dysynchrony index.

Abstract: A cardiac rhythm management system provides for the trending of a third heart sound (S3) index. The S3 index is a ratio, or an estimate of the ratio, of the number of S3 beats to the number of all heart beats, where the S3 beats are each a heart beat during which an occurrence of S3 is detected. An implantable sensor such as an accelerometer or a microphone senses an acoustic signal indicative heart sounds including S3. An S3 detector detects occurrences of S3 from the acoustic signal. A heart sound processing system trends the S3 index on a periodic basis to allow continuous monitoring of the S3 activity level, which is indicative of conditions related to heart failure.

Abstract: Method and apparatus for computer enabled analysis of ECG (electro cardiographic) data by exploiting computerized three-dimensional spatial presentation of the measured data using vectors. A three-dimensional presentation of the human heart may be correlated with waveforms specific for standard ECG or derived ECG signals based on the dipole approximation of the heart electrical activity. Additional tools for analyzing ECG data are also provided which may be used to determine the time of cardiac electrical events, to select specific beats for automated cardiac interval determination, and to flag ECGs that have been evaluated by automated means but may benefit by human reading.

Abstract: A method for providing a representation of the distribution, fluctuation and/or movement of electrical activity through heart tissue, said method comprising: obtaining an ECG of the heart comprising said tissue; obtaining a model of the heart geometry; obtaining a model of the torso geometry; relating the measurements per electrode of the ECG to the heart and torso geometry and estimating the distribution, fluctuation and/or movement of electrical activity through heart tissue based upon a fastest route algorithm, shortest path algorithm and/or fast marching algorithm.

Abstract: Methods for evaluating tissue motion of a tissue location, e.g., a cardiac location, via external continuous field tomography are provided. Aspects of the methods include generating at least one substantially linear continuous field gradient across the tissue location of interest, and using a resultant signal from a sensing element stably associated with the tissue location to evaluate motion of the tissue location. Also provided are systems, devices and related compositions for practicing the subject methods. The subject methods and devices find use in a variety of different applications, including cardiac resynchronization therapy.

Abstract: Various techniques are provided for calibrating and estimating left atrial pressure (LAP) using an implantable medical device, based on impedance, admittance or conductance parameters measured within a patient. In one example, default conversion factors are exploited for converting the measured parameters to estimates of LAP. The default conversion factors are derived from populations of patients. In another example, a correlation between individual conversion factors is exploited to allow for more efficient calibration. In yet another example, differences in thoracic fluid states are exploited during calibration. In still yet another example, a multiple stage calibration procedure is described, wherein both invasive and noninvasive calibration techniques are exploited. In a still further example, a therapy control procedure is provided, which exploits day time and night time impedance/admittance measurements.

Abstract: In some embodiments, a wearable physiologic monitor comprises a mixed analog and digital application-specific integrated circuit (ASIC) including signal conditioning circuitry, an A/D converter, a real-time clock, and digital control logic. The signal conditioning circuitry includes analog amplification circuitry, analog (continuous-time or switched capacitor) filtering circuitry before the A/D converter, and in some embodiments digital (DSP) filtering circuitry after the A/D converter. The monitor includes sensors such as electrocardiogram (ECG) electrodes, accelerometers, and a temperature sensor, some of which may be integrated on the ASIC. The digital control logic receives digital physiologic data sampled at different rates, assembles the data into physiologic data packets, time-stamps at least some of the packets, and periodically stores the packets in a digital memory. The monitor may include a disposable patch including the ASIC, and a reusable, removable digital memory such as flash memory card.

Abstract: The invention provides a system and method for measuring vital signs (e.g. SYS, DIA, SpO2, heart rate, and respiratory rate) and motion (e.g. activity level, posture, degree of motion, and arm height) from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed.

Abstract: The present disclosure relates to a sensor assembly, comprising a frame comprising structural supports, and housings configured to house an optical component; and a strut disposed between one of the structural supports and housings; wherein the struts are adapted to house conductors connecting the optical component to a circuit.

Abstract: An exemplary method includes providing at least two-dimensional position information, for at least two points in time, for an electrode located in a cardiac space; determining a local estimator based on the position information; and, based at least in part on the determined local estimator, selecting a configuration for delivering a cardiac pacing therapy or diagnosing a cardiac condition. Exemplary methods for regional estimators and exemplary methods for global estimators are also disclosed along with devices and systems configured to perform various methods.

Abstract: A method for adjusting a blood pressure measurement to compensate for a pressure offset due to obtaining the blood pressure measurement at an elevation other than heart level is illustrated. The method includes measuring a blood pressure at a location above or below a heart level and adjusting the measured blood pressure in accordance with a pressure difference between the location at which the blood pressure is obtained and the heart level.

Abstract: The present invention relates to advanced signal processing methods including digital wavelet transformation to analyze heart-related electronic signals and extract features that can accurately identify various states of the cardiovascular system. The invention may be utilized to estimate the extent of blood volume loss, distinguish blood volume loss from physiological activities associated with exercise, and predict the presence and extent of cardiovascular disease in general.

Abstract: The invention as disclosed is a non-contact method and apparatus for continuously monitoring a physiological event in a human or animal, such as blood pressure, which involves utilizing a laser-based interferometer system in combination with a laser tracking system and a signal processor to produce a waveform that is representative of a continuous physiological event such as blood pressure or respiration in a subject.

Abstract: The invention provides a body-worn monitor that measures a patient's vital signs (e.g. blood pressure, SpO2, heart rate, respiratory rate, and temperature) while simultaneously characterizing their activity state (e.g. resting, walking, convulsing, falling). The body-worn monitor processes this information to minimize corruption of the vital signs by motion-related artifacts. A software framework generates alarms/alerts based on threshold values that are either preset or determined in real time. The framework additionally includes a series of ‘heuristic’ rules that take the patient's activity state and motion into account, and process the vital signs accordingly. These rules, for example, indicate that a walking patient is likely breathing and has a regular heart rate, even if their motion-corrupted vital signs suggest otherwise.

Abstract: An exemplary method includes providing a mechanical activation time (MA time) for a myocardial location, the location defined at least in part by an electrode and the mechanical activation time determined at least in part by movement of the electrode; providing an electrical activation time (EA time) for the myocardial location; and determining an electromechanical delay (EMD) for the myocardial location based on the difference between the mechanical activation time (MA time) and the electrical activation time (EA time).

Abstract: Continuous remote monitoring of patients based on data obtained from an implantable hemodynamic monitor provides an interactive patient management system. Using network systems, patients are remotely monitored to continuously diagnose and treat heart-failure conditions. A screen displayable summary provides continuous feedback and information to physicians, patients and authorized third parties. The quick look summary includes various sites and presentation tailored to match the patients' and physicians' needs. The quick look summary further includes intelligent features that understand and retain the user's interests, preferences and use patterns. Patients, physicians and other caregivers are seamlessly connected to monitor and serve the chronic needs of heart-failure patients in a reliable and economic manner.

Abstract: An apparatus for outputting heart sounds includes an implantable system and an external system. The implantable system includes a sensor for generating sensed signals representing detected heart sounds, an interface circuit and a control circuit for receiving the sensed signals, generating data representing the heart sounds therefrom, and transmitting the data to the external system via the interface circuit. The external system includes an interface circuit for communicating with the implantable system, and a control circuit for receiving the data representing the heart sounds and for generating control signals that cause an output device to generate outputs representing the sounds. The implantable system may also include a sensor(s) for detecting cardiac electrical signals. In this case, outputs representing the cardiac electrical signals are also output.

Abstract: A medical device for sensing cardiac events that includes a plurality of electrodes sensing cardiac signals utilized to identify a cardiac event, a plurality of light sources capable of emitting light at a plurality of wavelengths, and a detector to detect the emitted light. A processor determines a plurality of light measurements in response to the emitted light detected by the detector, and generates a blood volume index in response to a light source of the plurality of light sources emitting light at an isobestic wavelength. The blood volume index is then utilized to verify the identifying of the cardiac event.

Abstract: Certain embodiments of the present invention are related to an implantable monitoring device to monitor a patient's arterial blood pressure, where the device is configured to be implanted subcutaneously. The device includes subcutaneous (SubQ) electrodes and a plethysmography sensor. Additionally, the device includes an arterial blood pressure monitor configured to determine at least one value indicative of the patient's arterial blood pressure based on at least one detected predetermined feature of a SubQ ECG and at least one detected predetermined feature of a plethysmography signal. Alternative embodiments of the present invention are directed to a non-implantable monitoring device to monitor a patient's arterial blood pressure based on features of a surface ECG and a plethysmography signal obtained from a non-implanted sensor.

Abstract: A living body state monitor apparatus includes: a living body information acquisition device to acquire living body information containing an electrocardiography waveform and a pulse waveform from a user; an irregular heartbeat detection section to detect an irregular heartbeat from the electrocardiography waveform; and a pulse wave feature quantity extraction section to extract a pulse wave feature quantity from a pulse wave corresponding to the irregular heartbeat. Further, a living body state determination section is included to determine a danger degree on user's living body state using both of (A) information on kind and/or continued time period of an irregular heartbeat detected by the irregular heartbeat detection section, and (B) a pulse wave feature quantity extracted by the pulse wave feature quantity extraction section, and/or a variation of the extracted pulse wave feature quantity.

Abstract: A patient management system is described that includes an implantable device for collecting one or more physiological parameter values and associated timestamps indicating the time at which the value is collected. The system is then configured to determine the periodic variation, if any, of a particular physiological parameter and use that periodicity in assessing changes in the parameter values over time.

Abstract: A patient monitor comprises: an electrocardiograph (14, 20) monitoring an electrocardiographic signal (40) of a patient (10); a secondary physiological signal monitor (16, 20) monitoring a second physiological signal (50) of the patient concurrently with the electrocardiograph monitoring the electrocardiographic signal of the patient; an alarm condition detector (42, 44) configured to detect an alarm condition based on the electrocardiographic signal of the patient; an alarm condition validator (52, 54, 56) configured to validate the alarm condition based on pulse regularity of a pulsatile component of the concurrently monitored second physiological signal of the patient; and an alarm indicator (24, 26, 58) configured to generate a human perceptible alarm conditional upon both the alarm condition detector detecting an alarm condition and the alarm condition validator validating the alarm condition.

Abstract: An image guided catheter navigation system for navigating a region of a patient includes an imaging device, a tracking device, a controller, and a display. The imaging device generates images of the region of the patient. The tracking device tracks the location of the catheter in the region of the patient. The controller superimposes an icon representing the catheter onto the images generated from the imaging device based upon the location of the catheter. The display displays the image of the region with the catheter superimposed onto the image at the current location of the catheter.

Abstract: The systolic timings of myocardia at various positions of a heart are analyzed and evaluated. An image processing apparatus 1 obtains myocardial thicknesses at various positions of a heart within a plurality of three dimensional images V1 through VK, obtained by imaging a heart at a plurality of temporal phases within a single cardiac cycle, at each of the temporal phases. The image processing apparatus 1 obtains representative values that represent the systolic phase of the myocardia at each position, based on the obtained myocardial thicknesses at each temporal phase, and outputs the obtained representative values.

Abstract: A method of estimating stroke volume of the heart is described. In this method, the volume of the heart is estimated from electrical impedance data of the chest, at two different phases of the cardiac cycle. The stroke volume is estimated from the difference between the volumes estimated at the two phases.

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.