Patent ID: 7774061

Claim:
A cardiac device, comprising: one or more sensing channels for sensing cardiac activity; one or more physiological sensors for sensing one or more variables related to cardiac ischemia; a therapy channel for delivering therapy to the heart; a controller for controlling the delivery of therapy in response to the sensed cardiac activity; and, wherein the controller is programmed to: collect a plurality of parameters associated with cardiac ischemia from the sensing channels and/or physiological sensors, where the plurality of parameters are designated X 1 through X n ; compute a vector-valued composite ischemia function that maps the plurality of parameters X 1 through X n to a vector with a plurality of components designated Y 1 through Y m that characterize the ischemia by: performing a regression analysis of historical values of the parameters and episodes of known ischemia, determining weighting coefficients from said analysis for each component of the vector-valued composite ischemia function, and computing each component of the vector-valued composite ischemia function as a weighted sum of one or more of the plurality of parameters using said weighting coefficients; and, adjust the manner in which the therapy is delivered by mapping the vector-valued composite ischemia function to a plurality of device behavior modifications designated Z 1 through Z k .