US Patent 10182742 Tissue contact sensing with a multi electrode ablation catheter

A method and system for assessing electrode-tissue contact before the delivery of ablation energy. The system may include a control unit programmed to determine a difference between a maximum impedance magnitude at a low frequency for a given electrode and an absolute minimum impedance magnitude at the low frequency across all electrodes, determine a difference between a maximum impedance magnitude at a high frequency for a given electrode and an absolute minimum impedance magnitude at the high frequency across all electrodes, and determine a difference between a maximum impedance phase at the high frequency for a given electrode and an absolute minimum impedance phase at the high frequency across all electrodes. Differences may be correlated to one another using a linear model, the results determining electrode-tissue contact status. The results may be displayed in a graphical format for easy communication to the user.