Abstract: A method includes placing a set of electrodes on a body surface of a patient's body. The method also includes digitizing locations for the electrodes across the body surface based on one or more image frames using range imaging and/or monoscopic imaging. The method also includes estimating locations for hidden ones of the electrodes on the body surface not visible during the range imaging and/or monoscopic imaging. The method also includes registering the location for the electrodes on the body surface with predetermined geometry information that includes the body surface and an anatomical envelope within the patient's body. The method also includes storing geometry data in non-transitory memory based on the registration to define spatial relationships between the electrodes and the anatomical envelope.

Abstract: In an example, an n-dimensional method of fundamental solution (MFS) is used to compute reconstructed electrical activity on a cardiac envelope based on geometry data and electrical data, where n is a positive integer greater than three. The electrical data represents electrical activity measured non-invasively from a plurality of locations distributed on a body surface of a patient, and the geometry data represents three-dimensional body surface geometry for the locations distributed on the body surface where the electrical activity is measured and three-dimensional heart geometry for the cardiac envelope.

Abstract: This disclosure relates to localization and tracking of an object. As one example, measurement data can be stored in memory to represent measured electrical signals at each of a plurality of known measurement locations in a given coordinate system in response to an applied signal at an unknown location in the given coordinate system. A dipole model cost function has parameters representing a dipole location and moment corresponding to the applied signal. A boundary condition can be imposed on the dipole model cost function. The unknown location in the given coordinate system, corresponding to the dipole location, can then be determined based on the stored measurement data and the dipole model cost function with the boundary condition imposed thereon.

Abstract: This disclosure provides one or more computer-readable media having computer-executable instructions for performing a method. The method includes storing geometry data representing a primary geometry of a cardiac envelope that includes nodes distributed across the cardiac envelope and geometry of a body surface that includes locations where electrical signals are measured. The body surface is spaced apart from the cardiac envelope. The method also includes perturbing the primary geometry of the cardiac envelope a given distance and direction to define the perturbed geometry of the cardiac envelope including nodes spaced from the nodes of the primary geometry. The method also includes computing reconstructed bipolar electrical signals on the nodes of the primary cardiac envelope based on the electrical signals measured from the body surface and the geometry data, including the primary and perturbed geometries of the cardiac envelope.

Abstract: This disclosure provides one or more computer-readable media having computer-executable instructions for performing a method. The method includes storing geometry data representing a primary geometry of a cardiac envelope that includes nodes distributed across the cardiac envelope and geometry of a body surface that includes locations where electrical signals are measured. The body surface is spaced apart from the cardiac envelope. The method also includes perturbing the primary geometry of the cardiac envelope a given distance and direction to define the perturbed geometry of the cardiac envelope including nodes spaced from the nodes of the primary geometry. The method also includes computing reconstructed bipolar electrical signals on the nodes of the primary cardiac envelope based on the electrical signals measured from the body surface and the geometry data, including the primary and perturbed geometries of the cardiac envelope.

Abstract: This disclosure relates to integrated channel integrity detection and to reconstruction of electrophysiological signals. An example system includes a input channels configured to receive respective electrical signals from respective electrodes. An amplifier stage includes a plurality of differential amplifiers, each of the differential amplifiers being configured to provide an amplifier output signal based on a difference between a respective pair of the electrical signals. Channel detection logic is configured to provide channel data indicating an acceptability of each of the input channels based on an analysis of a common mode rejection of the amplifier output signals.

Abstract: This disclosure relates to integrated channel integrity detection and to reconstruction of electrophysiological signals. An example system includes a plurality of input channels configured to receive respective electrical signals from a set of electrodes. An amplifier stage includes a plurality of differential amplifiers, each of the differential amplifiers being configured to provide an amplifier output signal based on a difference between a respective pair of the electrical signals. Channel detection logic is configured to provide channel data indicating an acceptability of each of the plurality of input channels based on an analysis of a common mode rejection of the amplifier output signals.

Abstract: Systems and methods for tomographic reconstruction of an image include systems and methods for producing images from k-space data. A k-space data set of an imaged object is acquired using know k-space data acquisition systems and methods. A portion of the k-space data set is sampled so as to collect some portion of the k-space data. An image is then reconstructed from the collected portion of the k-space data set according to a convex optimization model.

Abstract: One or more non-transitory computer-readable media have instructions executable by a processor and programmed to perform a method. The method includes analyzing the electrical data to locate one or more wave front lines over a given time interval. The electrical data represents electrophysiological signals distributed across a cardiac envelope for one or more time intervals. A respective trajectory is determined for each wave end of each wave front line that is located across the cardiac envelope over the given time interval. A set of connected trajectories are identified based on a duration that the trajectories are connected to each other by a respective wave front line during the given time interval. A connectivity association is characterized for the trajectories in the set of connected trajectories.

Abstract: For example, one or more non-transitory computer-readable media includes executable instructions to perform a method. The method includes defining a plurality of spatial regions distributed across a geometric surface. At least one wave front that propagates across the geometric surface is detected based on electrical data representing electrophysiological signals for each of a plurality of nodes distributed on the geometric surface over at least one time interval. An indication of conduction velocity of the wave front is determined for at least one spatial region of the plurality of spatial regions during the time interval based on a duration that the wave front resides within the at least one spatial region. Slow conduction activity is identified for the at least one spatial region based on comparing the indication of conduction velocity relative to a threshold. Conduction data is stored in memory to represent each slow conduction event.

Abstract: An example method includes analyzing morphology and/or amplitude of each of a plurality of electrophysiological signals across a surface of a patient's body to identify candidate segments of each signal satisfying predetermined conduction pattern criteria. The method also includes determining a conduction timing parameter for each candidate segment in each of the electrophysiological signals.

Abstract: Systems and methods for graph total variation (GTV) based reconstruction of electrical potentials on a cardiac surface are disclosed. GTV-based systems and methods incorporate information about the graph structure of the heart surface as well as imposing sparsity constraints on neighboring nodes. To this end, the present disclosure uses a novel way of calculating derivatives on irregular meshes, and provides a fast solver to compute an inverse solution more efficiently than in previous systems and methods. Moreover, fast-changing signals can be recovered with less smoothing and thus greater fidelity to the original signals.

Abstract: A map generator can be programmed to generate a multi-parameter graphical map by encoding at least two different physiological parameters for a geometric surface, corresponding to tissue of a patient, using different color components of a multi-dimensional color model such that each of the different physiological parameters is encoded by at least one of the different color components.

Abstract: An example method includes analyzing morphology and/or amplitude of each of a plurality of electrophysiological signals across a surface of a patient's body to identify candidate segments of each signal satisfying predetermined conduction pattern criteria. The method also includes determining a conduction timing parameter for each candidate segment in each of the electrophysiological signals.

Abstract: An example method includes applying a localization signal to a source electrode positioned within a conductive volume and a ground electrode at a known location. Electrical activity is sensed at a plurality of sensor electrodes distributed across an outer surface of the conductive volume. The locations of each of the sensor electrodes and the location of the ground electrode being stored in memory as part of geometry data. The electrical activity sensed at each of the sensor electrodes is stored in the memory as electrical measurement data. The method also includes computing a location of the source electrode by minimizing a difference between respective pairs of source voltages determined for the plurality of sensor electrodes. The source voltage for each of the sensor electrodes is determined based on the electrical measurement data and the geometry data.

Abstract: A map generator can be programmed to generate a multi-parameter graphical map by encoding at least two different physiological parameters for a geometric surface, corresponding to tissue of a patient, using different color components of a multi-dimensional color model such that each of the different physiological parameters is encoded by at least one of the different color components.

Abstract: For example, one or more non-transitory computer-readable media includes executable instructions to perform a method. The method includes defining a plurality of spatial regions distributed across a geometric surface. At least one wave front that propagates across the geometric surface is detected based on electrical data representing electrophysiological signals for each of a plurality of nodes distributed on the geometric surface over at least one time interval. An indication of conduction velocity of the wave front is determined for at least one spatial region of the plurality of spatial regions during the time interval based on a duration that the wave front resides within the at least one spatial region. Slow conduction activity is identified for the at least one spatial region based on comparing the indication of conduction velocity relative to a threshold. Conduction data is stored in memory to represent each slow conduction event.

Abstract: In an example, an n-dimensional method of fundamental solution (MFS) is used to compute reconstructed electrical activity on a cardiac envelope based on geometry data and electrical data, where n is a positive integer greater than three. The electrical data represents electrical activity measured non-invasively from a plurality of locations distributed on a body surface of a patient, and the geometry data represents three-dimensional body surface geometry for the locations distributed on the body surface where the electrical activity is measured and three-dimensional heart geometry for the cardiac envelope.

Abstract: This disclosure provides one or more computer-readable media having computer-executable instructions for performing a method. The method includes storing geometry data representing a primary geometry of a cardiac envelope that includes nodes distributed across the cardiac envelope and geometry of a body surface that includes locations where electrical signals are measured. The body surface is spaced apart from the cardiac envelope. The method also includes perturbing the primary geometry of the cardiac envelope a given distance and direction to define the perturbed geometry of the cardiac envelope including nodes spaced from the nodes of the primary geometry. The method also includes computing reconstructed bipolar electrical signals on the nodes of the primary cardiac envelope based on the electrical signals measured from the body surface and the geometry data, including the primary and perturbed geometries of the cardiac envelope.

Abstract: Systems and methods for cardiac fast firing (e.g., atrial fast firing) detection perform frequency analysis on channels of collected cardiac waveform data and test the data for outlier frequency complex content that is of higher frequency than baseline frequency complex content associated with cardiac fibrillation (e.g., atrial fibrillation) or other arrhythmogenic activity. Anatomical regions from whence the cardiac fast firing originates can be displayed in real time on an epicardial surface map via a graphical display, aiding administration of therapy. Prior to such detection, QRST complex removal can be performed to ensure that ventricular activity does not infect the atrial fast firing analysis. A frequency-based method for QRST complex removal is also disclosed.