Extracardiac autonomic nerve stimulation
The ExtraCardiac Nerve Stimulator and the ExtraCardiac Nerve Stimulation (ECANS) are, respectively, the apparatus and method to get remote nerve stimulation for medical applications. The system makes possible the stimulation without direct contact with the nerve based on special electrical wave. The remote nerve stimulation is extremely important for investigational and therapeutic proposals. The possibility of having this resource without surgical dissection, nerve exposure and tissue lesion with time-consuming process, is remarkable. This procedure relies on a settable stimulator with special features that releases a pulse wave with high frequency, very short pulse width, great amplitude, and precise current and time limitation connected to a special catheter, placed inside a vase or viscera. Frequency, pulse width, amplitude and time of application are operator adjustable to be effective against large patient variations, different anatomy, and areas of application. Special features prevent the application of the stimulus in the heart.
1 . An extracardiac autonomic nerve stimulator for stimulating at least one nerve in a patient, the extracardiac autonomic nerve stimulator comprising:
a non-implantable neurostimulator configured to be positioned external to the patient;
a catheter electrode operationally coupled to said neurostimulator, wherein said catheter electrode is configured to be positioned within a vein, artery, or viscera of the patient in measurable but non-contact proximity with respect to the at least one nerve, said neurostimulator configured to output a stimulation pulse wave to the catheter electrode; and
a Cardiac Electrical Potential Detection Unit (CEPDU) operatively coupled to said neurostimulator and said catheter electrode, said CEPDU configured to:
(i) detect a cardiac potential at said catheter electrode and inhibit release of said stimulation pulse wave to said catheter electrode upon detection of said cardiac potential at said catheter electrode; and
(ii) before releasing said stimulation pulse wave, perform cardiac pacing with an amplitude adjusted by an operator, wherein said CEPDU suspends the release of said stimulation pulse wave upon detection of a cardiac capture;
wherein:
said CEPDU only releases said stimulation pulse wave to said catheter electrode in the absence of detection of any cardiac electrical activity;
in response to receipt of the stimulation pulse wave from said neurostimulator, said catheter electrode is configured to stimulate neural activation of the at least one nerve through tissues of the patient while not being in contact with the at least one nerve; and
said neurostimulator is configured to adjust said stimulation pulse wave to have a frequency that is adjustable within a frequency range from and including 10 Hz to and including 100 Hz, to have a pulse width that is adjustable within a pulse width range from and including 10 microseconds to and including 50 microseconds, and to have an amplitude that is adjustable up to and including 80 V.
2 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein the at least one nerve comprises ganglia.
3 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein the extracardiac autonomic nerve stimulator is configured for use in analysis of electrophysiological cardiac responses by outputting the stimulation pulse wave that causes at least one of the electrophysiological cardiac responses detectable by one or more of: electrocardiogram (ECG) or visceral monitor (VM) operatively coupled with the patient.
4 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein said neurostimulator comprises a pulse generating circuit capable of generating the stimulation pulse wave with variable and controlled frequency, amplitude, pulse width, and stimulation time limitations, such that the extracardiac autonomic nerve stimulator is always within a safe window for stimulation of the at least one nerve.
5 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein said catheter electrode is configured to be only temporarily used for stimulation while being located inside of the vein, artery, or viscera of the patient.
6 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein the extracardiac autonomic nerve stimulator comprises an electric current limiter configured to prevent release of high electric current by said neurostimulator.
7 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein said neurostimulator comprises a multifunction display and a multifunction keyboard configured to allow an operator to modify operator preference parameters including the frequency, amplitude, pulse width, and pulse duration of said stimulation pulse wave.
8 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein said extracardiac autonomic nerve stimulator is at least temporarily connected to said catheter electrode, and wherein any bipolar electrophysiological catheter is usable as said catheter electrode.
9 . The extracardiac autonomic nerve stimulator according to claim 1 , wherein the extracardiac autonomic nerve stimulator is configured to stimulate not only the at least one nerve, but is also configured to facilitate intravisceral stimulation.
10 . A method of stimulating at least one nerve in a patient using an extracardiac autonomic nerve stimulator, the extracardiac autonomic nerve stimulator comprising a non-implantable neurostimulator configured to be positioned external to the patient, and a catheter electrode operationally coupled to said neurostimulator, the method comprising:
positioning said catheter electrode within a vein, artery, or viscera of the patient in measurable but non-contact proximity with respect to the at least one nerve;
outputting, using said neurostimulator, a stimulation pulse wave to said catheter electrode;
in response to receipt of said pulse wave from said neurostimulator, stimulating, using said catheter electrode, neural activation of the at least one nerve through tissues of the patient while not being in contact with the at least one nerve;
detecting, using a Cardiac Electrical Potential Detection Unit (CEPDU) operatively coupled to said neurostimulator and said catheter electrode, a cardiac potential at said catheter electrode and inhibit release of said stimulation pulse wave to said catheter electrode upon detection of said cardiac potential at said catheter electrode; and
before releasing said stimulation pulse wave, performing cardiac pacing with an amplitude adjusted by an operator, wherein said CEPDU suspends the release of said stimulation pulse wave upon detection of a cardiac capture;
wherein:
said CEPDU only releases said stimulation pulse wave to said catheter electrode in the absence of detection of any cardiac electrical activity; and
said neurostimulator adjusts said pulse wave by adjusting a frequency of said pulse wave so that said frequency is adjustable within a frequency range from and including 10 Hz to and including 100 Hz, by adjusting a pulse width of said pulse wave so that said pulse width is adjustable within a pulse width range from and including 10 microseconds to and including 50 microseconds, and by adjusting an amplitude of said pulse wave so that said amplitude is adjustable up to and including 80 V.
11 . The method of stimulating at least one nerve in a patient using an extracardiac autonomic nerve stimulator according to claim 10 , further comprising the step of removing said catheter electrode from the patient after the neural activation of the at least one nerve.