Tissue contact sensing using a medical device

A system for sensing tissue contact, comprising:

• a catheter shaft including a distal end portion, wherein the distal end portion includes a sensing assembly having a plurality of electrodes;
• wherein the plurality of electrodes includes a current-carrying electrode, a first sensing electrode and a second sensing electrode;
• wherein the first sensing electrode is positioned a first distance from the current-carrying electrode;
• wherein the second sensing electrode is positioned a second distance from the current-carrying electrode;
• wherein the first distance is different from the second distance;
• a processor, wherein the processor is designed to:
• simultaneously detect:
• (a) a first parameter based at least in part on the first and second distances, and
• (b) an impedance increase across at least one of the plurality of electrodes.

An electrophysiology medical device, comprising:

• a catheter shaft including a distal end portion;
• a sensing assembly having a plurality of electrodes, wherein the plurality of electrodes includes four or more terminals;
• wherein the four or more terminals includes one or more current-carrying electrodes and one or more sensing electrodes;
• wherein the one or more current-carrying electrodes, the one or more sensing electrodes, or both includes a mapping electrode;
• wherein the four or more terminals are designed to measure an electrical characteristic;
• and
• a processor coupled to the sensing assembly.