Abstract: Systems and methods can be used for ultrasound-based geometry determination for cardiac mapping. A patient can be scanned with an ultrasound while wearing body surface electrodes. While the scanning takes place, the location of the ultrasound transducer can be tracked in three-dimensional space. The electrodes can be tracked and located in the same coordinate system as the image volume. Therefore, each electrode's location can be determined relative to the acquired image volume such that corresponding geometry data is generated for the heart and the electrodes.

Abstract: Systems and methods can be used to provide an indication of heart function, such as an indication of mechanical function or hemodynamics of the heart, based on electrical data. For example, a method for assessing a function of the heart can include determining a time-based electrical characteristic for a plurality of points distributed across a spatial region of the heart. The plurality of points can be grouped into at least two subsets of points based on at least one of a spatial location for the plurality of points or the time-based electrical characteristics for the plurality of points. An indication of synchrony for the heart can be quantified based on relative analysis of the determined time-based electrical characteristic for each of the at least two subsets of points.

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 system (10) can localize an object in a patient's body. The system (10) can include a pulse generator (18 or 30) configured to provide a localization signal to at least one electrode that is fixed to the object in the patient's body. A sensor array (22) can be configured to detect an electrical field produced in response to the localization signal and provide respective sensor signals. A map generator (42) can be configured to reconstruct electrical signals based on the respective sensor signals and geometry data representing a geometric relationship between patient anatomy and the sensor array. A location calculator (50) can determine a location where the localization signal was applied based on the reconstructed electrical 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 receiving monitoring data representing one or more substantially real time electrical signals based on measurements from one or more respective electrodes. The method also includes selecting at least one signal of interest (SOI) from the monitoring data, each selected SOI being associated with a respective anatomical location and storing SOI data in memory corresponding to each selected SOI. The method also includes quantifying changes between signal characteristics of real time signals acquired for one or more respective anatomical locations and the at least one SOI that is associated with each of the respective anatomical locations. An output can be generated based on the quantifying to characterize spatially local signal changes with respect to each of the respective anatomical locations.

Abstract: An example method includes performing amplitude-based detection to determine location of R-peaks for a plurality of electrograms. The method also includes performing wavelet-based detection to determine location of R-peaks for the plurality of electrograms. The method also includes adjusting the location of the R-peaks determined by the wavelet-based detection of R-peaks based on the location of R-peaks determined by the amplitude-based detection of R-peaks. The method also includes storing, in memory, R-peak location data to specify R-peak locations for the plurality of electrograms based on the adjusting.

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: A non-transitory computer-readable medium can have instructions executable by a processor. The instructions can include an electrogram reconstruction method to generate reconstructed electrogram signals for each of a multitude of points residing on or near a predetermined cardiac envelope based on geometry data and non-invasively measured body surface electrical signals. The instructions can include a phase calculator to compute phase signals for the multitude of points based on the reconstructed electrogram signals and a visualization engine to generate an output based on the computed phase signals.

Abstract: Systems and methods are provided to detect and analyze arrhythmia drivers. In one example, a system can include a wave front analyzer programmed to compute wave front lines extending over a surface for each of the plurality of time samples based on phase information computed from electrical data at nodes distributed across the surface. A trajectory detector can be programmed to compute wave break points for each of the wave front lines and to determine a trajectory of at least one rotor core across the surface. A stability detector can be programmed to identify at least one stable rotor portion corresponding to subtrajectories of the determined trajectory.

Abstract: This disclosure provides isolation for a medical amplifier by providing a low impedance path for noise across an isolation barrier. The low impedance path can include a capacitive coupling between a patient ground, which is isolated from control circuitry, and a functional ground of an isolation system that is isolated from earth ground. The low impedance path can draw noise current from an input of an amplifier of patient circuitry.

Abstract: A method can include analyzing non-invasive electrical data for a region of interest (ROI) of a patient's anatomical structure to identify one or more zones within the ROI that contain at least one mechanism of distinct arrhythmogenic electrical activity. The method also includes analyzing invasive electrical data for a plurality of signals of interest at different spatial sites within each of the identified zones to determine intracardiac signal characteristics for the plurality of sites within each respective zone. The method also includes generating an output that integrates the at least one mechanism of distinct arrhythmogenic electrical activity for the one or more zones with intracardiac signal characteristics for the plurality of sites within each respective zone.

Abstract: A method to calculate and visualize dynamic wave front propagation of electrical signals on a geometric surface is described. Wave front locations are identified on the geometric surface between each identified pair of adjacent nodes on the geometric surface. A graphical map can be generated to represent the identified wave front locations on at least a portion of the geometric surface.

Abstract: A method includes storing baseline data representing at least one local or global electrical characteristics for at least a portion of a region of interest (ROI) of a patient's anatomical structure. The baseline data is determined based on electrical measurement data obtained during at least one first measurement interval. The method also includes storing in memory other data representing the at least one local or global electrical characteristics for the at least a portion of the ROI based on electrical measurement data obtained during at least one subsequent measurement interval. The method also includes evaluating the baseline data relative to the other data to determine a change in the at least one local or global electrical characteristics. The method also includes generating an output based on the evaluating to provide an indication of progress or success associated with the applying the treatment.

Abstract: A system includes an input to receive at least one electrophysiological signal representing cardiac electrical activity measured from a body surface of a patient. The system also includes a signal processor to analyze the at least one electrophysiological signal and compute a score having a value to indicate a likelihood of arrhythmogenic activity, the score being computed as a function of at least two of cycle length, amplitude and polarity of the at least one signal.

Abstract: A computer-implemented method can include determining an amplitude for each of a plurality of input channels, corresponding to respective nodes. A measure of similarity can be computed between the input channel of each node and the input channel of its neighboring nodes. The method can also include comparing an amplitude for each node relative to other nodes to determine temporary bad channels. For each of the temporary bad channels, a measure of similarity can be computed between the input channel of each node and the input channel of its neighboring nodes. Channel integrity can then be identified based on the computed measures of similarity.

Abstract: A method can include storing input electrical signal data representing at least a given electrophysiological signal acquired from a patient. A non-local mean filter can be applied to the given electrophysiological signal, the non-local mean filter including a spatial filter component and an intensity filter component. The method can also include controlling parameters to establish weighting of each of the spatial filter component and the intensity filter component in response to a control input. Filtered signal data can be stored based on the applying and the controlling.

Abstract: A method can determine one or more origins of focal activation. The method can include computing phase for the electrical signals at a plurality of nodes distributed across a geometric surface based on the electrical data across time. The method can determine whether or not a given candidate node of the plurality of nodes is a focal point based on the analyzing the computed phase and magnitude of the given candidate node. A graphical map can be generated to visualize focal points detected on the geometric surface.

Abstract: This disclosure provides isolation for a medical amplifier by providing a low impedance path for noise across an isolation barrier. The low impedance path can include a capacitive coupling between a patient ground, which is isolated from control circuitry, and a functional ground of an isolation system that is isolated from earth ground. The low impedance path can draw noise current from an input of an amplifier of patient circuitry.