In some embodiments, a method of applying stimulation pulse therapy to
excitable tissue may include one or more of the following steps: (a)
delivering a PESP stimulation therapy to the excitable tissue for a
cardiac cycle, (b) delivering a NES stimulation therapy to the excitable
tissue during certain cardiac cycles, (c) determining physiologic demand
of the patient based on at least one physiologic measurement, (d)
determining physiologic demand being placed on a heart based on at least
one physiologic measurement, and ceasing the delivery of the NES and PESP
stimulation therapy when physiologic demand returns to a base level, and
(e) determining physiologic demand being placed on a heart based on at
least one physiologic measurement, and modulating the ratio of the number
of cardiac cycles in which the NES stimulation therapy is delivered to
the number of cardiac cycles in which the PESP stimulation therapy is
delivered based on physiologic demand.