Selective stimulation to modulate the sympathetic nervous system
Systems, methods and devices are provided for the targeted treatment of a variety of medical conditions by directly neuromodulating a target anatomy associated with the condition while minimizing or excluding undesired neuromodulation of other anatomies. Typically, the target anatomy includes one or more dorsal root ganglia, dorsal roots, dorsal root entry zones, or portions thereof. Such target stimulation areas are utilized due in part to their effect on the sympathetic nervous system.
1. A method of treating myocardial ischemia in a patient by modulating a neural pathway in the sympathetic nervous system, comprising:
identifying myocardial ischemia in the patient;
positioning at least one electrode on a dorsal root ganglion epinurium in close proximity to the dorsal root ganglion of the patient upstream of at least one ganglion of the sympathetic nerve chain, wherein the dorsal root ganglion is located within T2 to T6 spinal segments; and
treating myocardial ischemia in the patient by increasing blood flow in the coronary vascular system through provision of electrical pulses to the at least one electrode so as to directly neuromodulate the dorsal root ganglion in a manner that influences a condition associated with the at least one ganglion of the sympathetic nerve chain while excluding neuromodulation of an associated ventral root.
2. The method of claim 1 wherein the treating is applied when the patient is experiencing an episode of angina pectoris.
3. The method of claim 1 wherein the treating is applied when the patient is experiencing an episode of coronary spasm.
4. The method according to claim 1 further comprising directly applying stimulation to the at least one ganglion along the sympathetic nerve chain.
5. The method according to claim 4 wherein the directly applying stimulation step for the at least one ganglion along the sympathetic nerve chain is performed using an electrode exposed to the at least one ganglion along the sympathetic nerve chain.
6. The method of claim 1 wherein the positioning comprises implanting the at least one electrode through an epidural space of the patient through a foramen into position in close proximity to the dorsal root ganglion.
7. The method of claim 1 wherein the positioning comprises implanting the at least one electrode without entry into the spinal column of the patient.
8. The method of claim 1 further comprising:
employing a sensor to sense a physiological condition of the patient relevant to myocardial ischemia in the patient to control application of stimulation pulses to the dorsal root ganglion.
9. The method of claim 8 wherein the sensor generates a signal indicative of one item selected from the list consisting of: heart rate, blood pressure, arterial pressure, blood flow, cardiac perfusion, electrocardiogram activity, and blood oxygenation.