1. A method for operating an implanted neural stimulation device having an electrode, comprising: implementing a neural stimulation therapy stored in the implanted neural stimulation device, wherein the neural stimulation therapy includes a programmed duty cycle, and the programmed duty cycle includes a stimulation ON portion followed by a stimulation OFF portion; remotely detecting cardiac activity using the electrode to detect heart rate information during at least one of the stimulation ON portion or during the stimulation OFF portion; and controlling the neural stimulation therapy using the detected heart rate information.