Patent ID: 7657312

Claim:
An implantable device for delivering cardiac function therapy to a patient, comprising: a plurality of pacing channels for delivering pacing pulses to multiple ventricular sites; a parasympathetic stimulation channel for stimulating parasympathetic nerves innervating the heart; a sensor for measuring cardiac output; an exertion level sensor for measuring the patient's exertion level; a controller for controlling the delivery of pacing pulses to the multiple ventricular sites in accordance with a programmed pacing mode; wherein the controller is programmed to deliver multi-site ventricular pacing therapy in conjunction with parasympathetic stimulation and wherein the controller is further programmed to deliver the multi-site ventricular pacing therapy with a pacing pulse output sequence that pre-excites at least one myocardial region relative to other regions for reducing ventricular wall stress; wherein the controller is further programmed to deliver the multi-site ventricular pacing in accordance with a demand pacing mode that counteracts slowing of the heart rate by the parasympathetic stimulation so that no slowing of the heart rate occurs; and, wherein the controller is programmed to compute a function that maps exertion levels to minimum cardiac output values considered to be adequate for a particular exertion level and is further programmed to cease the delivery of parasympathetic stimulation if a presently measured cardiac output is below the minimum cardiac output indicated as adequate by the computed function.