Patent ID: 6928323

Claim:
A cardiac rhythm management device, comprising: first and second sensing channels for sensing electrical activity in a first heart chamber and a second heart chamber, respectively; circuitry for detecting a first chamber sense when the sensed electrical activity in the first sensing channel exceeds a first channel sensing threshold which has a minimum level equal to a specified first channel steady-state value; circuitry for detecting a second chamber sense when the sensed electrical activity in the second sensing channel exceeds a second channel sensing threshold which has a minimum level equal to a specified second channel steady-state value; circuitry for measuring a peak amplitude of a post-sense far-field signal generated in the first sensing channel after a second chamber sense is detected; and, circuitry for rendering the first sensing channel refractory for a post-sense cross-chamber refractory period after detection of a second chamber sense by raising the first channel sensing threshold above the first channel steady-state value, wherein the first channel sensing threshold is raised during the post-sense cross-chamber refractory period to a post-sense cross-chamber maximum refractory value derived from the measured peak amplitude of the post-sense far-field signal.