Contingent cardio-protection for epilepsy patients

Abstract

Disclosed are methods and systems for treating epilepsy by stimulating a main trunk of a vagus nerve, or a left vagus nerve, when the patient has had no seizure or a seizure that is not characterized by cardiac changes such as an increase in heart rate, and stimulating a cardiac branch of a vagus nerve, or a right vagus nerve, when the patient has had a seizure characterized by cardiac changes such as a heart rate increase.

What is claimed: 
     
         1 . A method of treating a medical condition in a patient using an implantable medical device, the implantable medical device including a first electrode coupled to a first cranial nerve structure and a second electrode coupled to a second cranial nerve structure, where the first cranial nerve structure is a left portion of a cranial nerve and the second cranial nerve structure is a right portion of the cranial nerve, the method comprising:
 detecting a seizure in a patient based on at least one first body signal of the patient selected from an autonomic signal, a neurologic signal, a metabolic signal, an endocrine signal, and a tissue stress marker signal;   providing a first electrical signal to the first cranial nerve structure of the patient;   providing a second electrical signal to the second cranial nerve structure;   analyzing at least one second body signal of the patient selected from an autonomic signal, a neurologic signal, a metabolic signal, an endocrine signal, and a tissue stress marker signal;   determining, based on the analyzing of the at least one second body signal, at least a first classification index comprising at least one of an epileptic seizure index and a non-epileptic seizure index; and   classifying the seizure as one of a non-epileptic seizure or an epileptic seizure based on the at least the first classification index.   
     
     
         2 . The method of  claim 1 , wherein the first electric signal increases a sympathetic tone to increase the heart rate of the patient. 
     
     
         3 . The method of  claim 1 , wherein the first electric signal decreases a parasympathetic tone to increase the heart rate of the patient. 
     
     
         4 . The method of  claim 1 , wherein the first electric signal decreases a sympathetic tone to decrease the heart rate of the patient. 
     
     
         5 . The method of  claim 1 , wherein the first electric signal increases a parasympathetic tone to decrease the heart rate of the patient. 
     
     
         6 . The method of  claim 1 , wherein based on a determination that a seizure is characterized by a decrease in the heart rate of the patient, the first electric signal is applied to block action potential conduction on the vagus nerve. 
     
     
         7 . The method of  claim 1 , further comprising a heart unit and the method further comprising determining an inter-maxima interval and an inter-minima interval between a first oscillation and a second oscillation via the heart unit. 
     
     
         8 . The method of  claim 7 , further comprising a logic unit and the method further comprising comparing the inter-maxima interval and the inter-minima interval to an interval threshold via the logic unit. 
     
     
         9 . The method of  claim 8 , further comprises initiating one or more actions based on the interval threshold being reached. 
     
     
         10 . A system for treating a medical condition in a patient, comprising:
 a sensor for sensing at least one body data stream;   at least one electrode coupled to a vagus nerve of the patient;   a programmable electrical signal generator;   a heart rate unit capable of determining a heart rate of the patient based on the at least one body data stream; and   a logic unit configured via one or more processors to compare a monitored value which is determined based on one or more data points relating to the heart rate to one or more threshold values, the logic unit further configured to determine a first triggering event based on the comparison;   wherein the one or more processors are configured to initiate one or more actions to change the heart rate of the patient based on the determination of the first triggering event.   
     
     
         11 . The system of  claim 10 , wherein the one or more processors are configured to increase a sympathetic tone or to decrease a sympathetic tone to increase the heart rate of the patient based on the first triggering event. 
     
     
         12 . The system of  claim 10 , wherein the logic unit is further configured to determine a second triggering event based on the comparison. 
     
     
         13 . The system of  claim 12 , wherein the one or more processors are configured to decrease a sympathetic tone to decrease the heart rate of the patient based on the second triggering event. 
     
     
         14 . The system of  claim 10 , wherein the logic unit is further configured to determine a third triggering event based on the comparison. 
     
     
         15 . The system of  claim 14 , wherein the one or more processors are configured to decrease the parasympathetic tone to increase the heart rate of the patient based on the third triggering event. 
     
     
         16 . The system of  claim 10 , wherein the logic unit is further configured to determine an Nth triggering event based on the comparison. 
     
     
         17 . The system of  claim 16 , wherein the one or more processors are configured to increase the sympathetic tone to increase the heart rate of the patient based on the Nth triggering event.