Patent ID: 8103338

Claim:
A method comprising: inserting a catheter into a heart, the catheter comprising three or more 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 of the electrodes; for each of a plurality of catheter locations, determining a local surface of at least a portion of the heart based on the measured electrical signals and determining valid and invalid areas of the local surface, the valid areas corresponding to an endocardial boundary; determining a representation of a chamber anatomy of at least a portion of the heart based on multiple ones of the valid areas of the local surfaces, the determined representation of a chamber anatomy of at least a portion of the heart representing an area larger than any one of the local surfaces; and displaying at least a portion of the determined representation of the chamber anatomy of the at least a portion of the heart with a first visual indicia indicative of the determined valid area corresponding to the endocardial boundary.