Abstract: A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

Abstract: A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

Abstract: A method of tracking a position of a catheter within a patient includes securing a navigational reference at a reference location within the patient, defining the reference location as the origin of a coordinate system, determining a location of an electrode moving within the patient relative to that coordinate system, monitoring for a dislodgement of the navigational reference from the initial reference location, for example by measuring the navigational reference relative to a far field reference outside the patient's body, and generating a signal indicating that the navigational reference has dislodged from the reference location. Upon dislodgement, a user may be provided with guidance to help reposition and secure the navigational reference to the initial reference location, or the navigational reference may be automatically repositioned and secured to the initial reference location. Alternatively, a reference adjustment may be calculated to compensate for the changed reference point/origin.

Abstract: A system and method for assessing contact between a medical device and tissue may comprise an electronic control unit (ECU) configured to be coupled to a medical device, the medical device comprising a first electrode and a second electrode. The ECU may be further configured to select the first electrode as an electrical source and the second electrode as an electrical sink, to cause an electrical signal to be driven between the source and sink, to detect respective electric potentials on the first electrode and the second electrode while the electrical signal is driven, and to determine an impedance respective of one of the first electrode and the second electrode according to both of the respective electric potentials.

Abstract: A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

Abstract: A system and method for assessing contact between a medical device and tissue may comprise an electronic control unit (ECU) configured to be coupled to a medical device, the medical device comprising a first electrode and a second electrode. The ECU may be further configured to select the first electrode as an electrical source and the second electrode as an electrical sink, to cause an electrical signal to be driven between the source and sink, to detect respective electric potentials on the first electrode and the second electrode while the electrical signal is driven, and to determine an impedance respective of one of the first electrode and the second electrode according to both of the respective electric potentials.

Abstract: A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

Abstract: A platen for a metallographic grinder has an outer peripheral rim with an upper surface having a lower height. Also, fingers engaging a specimen are allowed to move laterally (i.e., wobble) to minimize the tipping forces on the specimen during the grinding process. Either one or both of these structures can be employed and results in a much flatter specimen surface for use in subsequent analysis.

Abstract: Electrode assemblies include segmented electrodes disposed on a catheter. The segmented electrodes can be constructed at the tip of the catheter. Tip electrodes can be constructed from an electrically insulative substrate comprising an inner lumen, an external tip surface, and a plurality of channels extending from the inner lumen to the external tip surface, a plurality of segmented electrodes, and a plurality of spot electrodes. Each of the plurality of segmented electrodes and each of the plurality of spot electrodes can be laterally separated from each other by an electrically non-conductive substrate portion and each of the spot electrodes and each of the segmented electrodes can be electrically coupled to at least one wire or conductor trace.

Abstract: Electrode assemblies include segmented electrodes disposed on a catheter. The segmented electrodes can be constructed at the tip of the catheter. Tip electrodes can be constructed from an electrically insulative substrate comprising an inner lumen, an external tip surface, and a plurality of channels extending from the inner lumen to the external tip surface, a plurality of segmented electrodes, and a plurality of spot electrodes. Each of the plurality of segmented electrodes and each of the plurality of spot electrodes can be laterally separated from each other by an electrically non-conductive substrate portion and each of the spot electrodes and each of the segmented electrodes can be electrically coupled to at least one wire or conductor trace.

Abstract: A method of monitoring contact between a probe and a tissue surface includes placing the probe in proximity to the surface, robotically moving the probe, measuring a tissue parameter at the distal end of the probe, calculating an amount of change in the measured tissue parameter between measurements thereof, and indicating a change in proximity or degree of contact between the probe and the surface based upon the amount of change. The indication of change may be based directly upon the calculated amount of change in the measured parameter or upon a calculated rate of change in the parameter. The rate of change may be relative to the time between measurements or the distance traveled by the probe between measurements, and may be calculated as a first, second, or other derivative of the tissue parameter.

Abstract: A method of tracking a position of a catheter within a patient includes securing a navigational reference at a reference location within the patient, defining the reference location as the origin of a coordinate system, determining a location of an electrode moving within the patient relative to that coordinate system, monitoring for a dislodgement of the navigational reference from the initial reference location, for example by measuring the navigational reference relative to a far field reference outside the patient's body, and generating a signal indicating that the navigational reference has dislodged from the reference location. Upon dislodgement, a user may be provided with guidance to help reposition and secure the navigational reference to the initial reference location, or the navigational reference may be automatically repositioned and secured to the initial reference location. Alternatively, a reference adjustment may be calculated to compensate for the changed reference point/origin.

Abstract: A system for determining the dimensions of a native valve annulus may include a sensing catheter, a transmitter, and a computing device. The sensing catheter may include a shaft extending in a longitudinal direction; a plurality of splines attached to the shaft, the splines having an expanded condition spaced radially outward from the shaft; and at least one sensing coil located on each of the splines. The transmitter may generate a magnetic field to induce a potential in each of the sensing coils, and the computing device may identify the positions of the sensing coils based on the induced potentials.

Abstract: A method of tracking a position of a catheter within a patient includes securing a navigational reference at a reference location within the patient, defining the reference location as the origin of a coordinate system, determining a location of an electrode moving within the patient relative to that coordinate system, monitoring for a dislodgement of the navigational reference from the initial reference location, for example by measuring the navigational reference relative to a far field reference outside the patient's body, and generating a signal indicating that the navigational reference has dislodged from the reference location. Upon dislodgement, a user may be provided with guidance to help reposition and secure the navigational reference to the initial reference location, or the navigational reference may be automatically repositioned and secured to the initial reference location. Alternatively, a reference adjustment may be calculated to compensate for the changed reference point/origin.

Abstract: A system for determining a location of an electrode of a medical device (e.g., a catheter) in a body of a patient includes a localization block for producing an uncompensated electrode location, a motion compensation block for producing a compensation signal (i.e., for respiration, cardiac, etc.), and a mechanism for subtracting the compensation signal from the uncompensated electrode location. The result is a corrected electrode location substantially free of respiration and cardiac artifacts. The motion compensation block includes a dynamic adaptation feature which accounts for changes in a patient's respiration patterns as well as intentional movements of the medical device to different locations within the patient's body. The system further includes an automatic compensation gain control which suppresses compensation when certain conditions, such as noise or sudden patch impedance changes, are detected.

Abstract: A system for detecting the dimensions and geometry of a native valve annulus for trans-catheter valve implantation includes a compliant balloon and a shaft within the balloon. One or more drive electrodes may be affixed to a surface of the balloon, and one or more sense electrodes may be affixed to the shaft. After insertion of the balloon into the native valve annulus, the drive electrodes may be energized with a predetermined voltage. Using a trained statistical model and the voltages measured at the sense electrodes, initial estimates of the cross-section of the valve annulus may be obtained. The initial estimates may then be provided to an optimization model of the valve annulus to obtain a highly accurate prediction of the cross-section of the valve annulus.

Abstract: A transmitting element for generating a magnetic field for tracking of an object includes a first spiral trace that extends from a first outer origin inward to a central origin in a first direction. A second spiral trace can extend from the central origin outward to a second outer origin in the first direction. The second spiral trace can extend from the central origin to the second outer origin in the first direction. The first spiral trace and the second spiral trace can be physically connected at the central origin to form the fluorolucent magnetic transmitting element and at least a portion of the first spiral trace overlaps at least a portion of the second spiral trace.

Abstract: A system for determining a location of an electrode of a medical device (e.g., a catheter) in a body of a patient includes a localization block for producing an uncompensated electrode location, a motion compensation block for producing a compensation signal (i.e., for respiration, cardiac, etc.), and a mechanism for subtracting the compensation signal from the uncompensated electrode location. The result is a corrected electrode location substantially free of respiration and cardiac artifacts. The motion compensation block includes a dynamic adaptation feature which accounts for changes in a patient's respiration patterns as well as intentional movements of the medical device to different locations within the patient's body. The system further includes an automatic compensation gain control which suppresses compensation when certain conditions, such as noise or sudden patch impedance changes, are detected.

Abstract: A system and method for assessing contact between a medical device and tissue may comprise an electronic control unit (ECU) configured to be coupled to a medical device, the medical device comprising a first electrode and a second electrode. The ECU may be further configured to select the first electrode as an electrical source and the second electrode as an electrical sink, to cause an electrical signal to be driven between the source and sink, to detect respective electric potentials on the first electrode and the second electrode while the electrical signal is driven, and to determine an impedance respective of one of the first electrode and the second electrode according to both of the respective electric potentials.

Abstract: A system for ablating tissue includes an ablation catheter for insertion into the body of a patient and a robotic controller for moving the catheter within the body. The robotic controller advances the catheter until the catheter contacts the tissue surface, maintains contact between the catheter and the tissue surface, and moves the catheter along a predetermined path to create a substantially continuous lesion of ablated tissue. A display device may be used to present a graphical representation of an area of tissue to be ablated. A user interface permits selection of a plurality of treatment points on the graphical representation. The interface is preferably coupled to the controller and catheter such that the controller may cause the catheter to automatically ablate tissue at and between the plurality of treatment points in response to the received user input.