Vagus nerve stimulation method

A method of treating a medical condition in a patient that is breathing and has a brain, a vagus nerve, and a heart with a heart rate variability, the heart generating a cardiac signal having a QRS wave portion, the method comprising:

• restricting the patient's breathing to increase the heart rate variability;
• detecting a portion of the QRS wave portion of the patient's cardiac signal;
• after detecting the portion of the QRS wave portion, generating a microburst comprising 2 to 20 electrical pulses;
• and
• delivering the microburst to the vagus nerve of the patient, the microburst delivered to the vagus nerve evoking a response in the brain of the patient.

A method of treating a medical condition in a patient having a brain, a vagus nerve, and a heart that generates a cardiac signal having a QRS wave portion, the method comprising:

• identifying the QRS wave portion of the cardiac signal;
• after identifying the QRS wave portion and before identifying a next sequential QRS wave portion, generating a plurality of microbursts, each microburst of the plurality of microbursts being patterned and comprising a series of electrical pulses, sequential electrical pulses of each microburst being separated by an interpulse interval, the sum of the interpulse intervals separating the pulses of each microburst being less than about 60 milliseconds;
• and
• delivering the plurality of microbursts directly to a selected location on the vagus nerve of the patient, the plurality of microbursts delivered to the vagus nerve evoking a response in the brain of the patient,
• wherein sequential microbursts of the plurality of microbursts are separated by at least 100 milliseconds.

A method of treating a medical condition in a patient that is breathing and has a brain, a vagus nerve, and a heart with a heart rate variability, a heart generating a cardiac signal having a QRS wave portion, the method comprising:

• restricting the patient's breathing to increase the heart rate variability;
• detecting the QRS wave portion of the cardiac signal;
• generating a microburst comprising a series electrical pulses separated by an interpulse interval, the sum of the interpulse intervals separating the pulses being less than 60 milliseconds;
• and
• delivering the microburst to the vagus nerve of the patient, the microburst delivered to the vagus nerve evoking a response in the brain of the patient.

A system for treating a medical condition in a patient having a brain, a vagus nerve, and a heart that generates a cardiac signal having a QRS wave portion, the system comprising:

• a communication interface configured to receive at least a select portion of the QRS wave portion of the cardiac signal;
• an electrical signal generator configured to generate a plurality of microbursts after the receipt of the select portion of the QRS wave portion by the communication interface and before receiving a select portion of a next sequential QRS wave portion by the communication interface, each microburst of the plurality of microbursts being patterned, comprising a series of electrical pulses, and having a duration of less than about one second, adjacent ones of the electrical pulses of each microburst being separated from one another by an interpulse interval of less than about 40 milliseconds, sequential microbursts of the plurality of microbursts being separated by at least 100 milliseconds;
• and
• an electrode in electrical communication with the vagus nerve, the electrode being configured to deliver the plurality of microbursts to a select location on the vagus nerve of the patient, the plurality of microbursts delivered to the vagus nerve evoking a response in the brain of the patient.

A non-transitory computer readable medium having computer executable components for

• identifying a QRS wave portion of a cardiac cycle;
• after identifying a first QRS wave portion of the cardiac cycle and before identifying a next sequential QRS wave portion of the cardiac cycle, generating a plurality of microbursts, each microburst of the plurality of microbursts being patterned and having 2 to 20 electrical pulses, adjacent ones of the electrical pulses being separated from one another by an interpulse interval of less than about 40 milliseconds;
• and
• delivering the plurality of microbursts via an electrode to a select location on the vagus nerve of a patient, the plurality of microbursts delivered to the vagus nerve evoking a response in a brain of the patient,
• wherein sequential microbursts of the plurality of microbursts are separated by at least 100 milliseconds.

A method of maximizing a vagal evoked potential (VEP) in a patient having a brain, a vagus nerve, and a heart that generates a cardiac signal having a QRS wave portion, the method comprising:

• identifying a select portion of the QRS wave portion of the patient's cardiac signal;
• after identifying the select portion of the QRS wave portion and before identifying a select portion of a next sequential QRS wave portion, generating a plurality of microbursts, each microburst of the plurality of microbursts being patterned and comprising a plurality of electrical pulses, adjacent ones of the electrical pulses being separated from one another by an interpulse interval of less than about 40 milliseconds;
• and
• delivering the plurality of microbursts directly to a selected location on the vagus nerve of the patient, the plurality of microbursts delivered to the vagus nerve evoking a response in the brain of the patient,
• wherein sequential microbursts of the plurality of microbursts are separated by an interburst interval of at least 100 milliseconds, and
• wherein, within at least one microburst of the plurality of microbursts, at least one interpulse interval is selectively varied from the other interpulse intervals.