Impedance based anatomy generation

A method comprising:

• inserting a catheter into a heart, the catheter comprising multiple, spatially distributed electrodes including multiple sets of electrodes each set comprising at least two electrodes;
• for each of the multiple different sets of electrodes, causing current to flow between at least some of the electrodes and in response to current flow, measuring an electrical signal at each of one or more measuring electrodes;
• and
• determining anatomical information about the heart by detecting a boundary of the heart based at least in part on impedance information generated based on the measured signals, wherein:
• the anatomical information accounts for a change in conductivity at the cardiac chamber boundary with a first conductivity inside the cardiac chamber boundary and a second conductivity outside the cardiac chamber boundary, the first conductivity being different from the second conductivity;
• and
• the anatomical information comprises a representation of at least a portion of a boundary of the heart.

A system comprising:

• a catheter comprising multiple, spatially distributed electrodes including multiple sets of electrodes each set comprising at least two electrodes, the electrodes being configured to inject a current and to measure electrical signals in response to the injected current;
• and
• a processing unit configured to determine anatomical information about the heart by detecting a boundary of the heart based at least in part on impedance information generated based on the measured signals, wherein:
• the anatomical information accounts for a change in conductivity at the cardiac chamber boundary with a first conductivity inside the cardiac chamber boundary and a second conductivity outside the cardiac chamber boundary, the first conductivity being different from the second conductivity;
• and
• the anatomical information comprises a representation of at least a portion of a boundary of the heart.