1. A medical system comprising: a first electrode coupled to a main trunk of a vagus nerve of a patient; a second electrode coupled to a cardiac branch of the vagus nerve of the patient; an electrical signal generator coupled to the first electrode and the second electrode; and one or more processors configured to: receive at least one body data stream; analyze the at least one body data stream using a seizure detection algorithm to determine an epileptic seizure state; apply a first electrical signal from the electrical signal generator to the main trunk of the vagus nerve using the first electrode as a cathode, based on a first determination that the epileptic seizure state of the patient is a first state where an epileptic seizure is not detected; and apply a second electrical signal from the electrical signal generator to the cardiac branch of the vagus nerve using the second electrode as the cathode, based on a second determination that the epileptic seizure state of the patient is a second state where the epileptic seizure is detected.