Patent ID: 11452484

Abstract:
A medical apparatus includes a shaft for insertion into an organ of a patient, an expandable frame, a plurality of diagnostic electrodes, a respective plurality of reference electrodes, and a processor. The expandable frame is coupled to a distal end of the shaft, extending along a longitudinal axis and including a plurality of expandable spines disposed about the longitudinal axis. The plurality of diagnostic electrodes, disposed on external surfaces of the expandable spines, are configured to sense diagnostic signals when in contact with tissue. The respective plurality of reference electrodes, disposed on internal surfaces of the expandable spines directly opposite the diagnostic electrodes, is electrically insulated from the tissue and is configured to sense interfering signals. The processor is configured to receive the diagnostic signals sensed by the diagnostic electrodes, receive the interfering signals sensed by the respective reference electrodes, and calculate corrected diagnostic signals by subtracting the interfering signals from the diagnostic signals.