Method for stimulating myocardial activity during the refractory period

摘要

Systems and methods for improving cardiac contraction during a patient's cardiac function cycle (beat) require detecting a local electrical event (depolarization) during that cycle. This local electrical event is then used to trigger the stimulation interval Δt at time t0. Importantly, the stimulation interval Δt is set to end at time t1 during the absolute refractory period of the cardiac function cycle. At time t1, the stimulator is triggered to stimulate local sympathetic nerves on the epicardial surface of the heart. This stimulation causes the sympathetic nerve to secrete norepinephrine and improve subsequent heart contraction.