Implantable electrical nerve stimulator/pacemaker with ischemia for decreasing cardiac workload

A system for influencing the natural biological blood pressure regulatory system of a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse stimulation of the patient's nerve system, said system comprising:

• electrode means coupled to said patient's heart for detecting the patient's electrocardiogram;
• means for receiving said patient's electrocardiogram and developing a signal representative of the ST segment of that electrocardiogram;
• means for providing an ST segment variation threshold value;
• means for comparing the derived ST segment to said ST segment variation threshold level and providing an ST segment output signal when the measured ST segment variation varies from the ST segment variation threshold value in a predetermined manner;
• and
• means responsive to said ST segment output signal for applying electric stimulation pulses to said nerve system.

A method of influencing the natural biological blood pressure regulatory system in a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse stimulation of the patient's nerve system, comprising the steps of:

• sensing a constituent of the venous return blood draining from myocardial tissue and producing an output signal substantially representing a chemical constituent of that blood;
• comparing said output signal to a set point threshold value and developing a stimulation trigger signal in response to a magnitude indicative of a condition of ischemia;
• and
• applying electric stimulation pulses to said nerve system in response to said trigger signal.

A method of influencing the natural biological blood pressure regulatory system in a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse stimulation of the patient's nerve system said method comprising the steps of:

• detecting said patient's electrocardiogram and developing a signal representative of the ST segment variation of that electrocardiogram;
• comparing the derived ST segment variation to an ST segment variation threshold level and providing an ST segment output signal when the measured ST segment variation varies from the ST segment variation threshold in a predetermined manner;
• and
• applying electric stimulation pulses to said nerve system in response to said ST segment output signal.

A method of influencing the natural biological blood pressure regulatory system in a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse stimulation of the patients's nerve system, comprising the steps of:

• continuously measuring the electrogram of the patient's heart;
• detecting certain characteristics of said electrogram indicative of an ischemia condition of the myocardium;
• initiating the storage of a sequence of said characteristics of said electrogram upon detection of an ischemic condition;
• delivering one or more electrical stimulation therapies to the patient's nervous system for depressing the patient's heart rate;
• and
• initiating the storage of a further sequence of said characteristics of said electrogram following delivery of said stimulation therapies.

A system for influencing the natural biological blood pressure regulatory system in a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse, stimulation of the patient's nerve system, said system comprising:

• means for continuously measuring the electrogram of the patient's heart;
• means for detecting certain characteristics of said electrogram indicative of an ischemic condition of the myocardriom;
• means for initiating the storage of a sequence of said characteristics of said electrogram upon detection of an ischemic condition;
• means for delivering one or more electrical stimulation therapies to the patient's nervous system for depressing the patient's heart rate;
• and
• means for initiating the storage of a further sequence of said characteristics of said electrogram following delivery of said stimulation therapies.

A method of influencing the natural biological blood pressure regulatory system in a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse stimulation of the patient's nerve system, comprising the steps of:

• sensing a constituent of the venous return blood draining from myocardial tissue and producing an output signal substantially representing a chemical constituent of that blood;
• comparing said output signal to a set point threshold value and developing a stimulation trigger signal in response to a magnitude indicative of a condition of ischemia;
• and
• applying electric stimulation pulses to said nerve system and storing said output signal in response to said trigger signal.

A system for influencing the natural biological blood pressure regulatory system in a patient, for reducing and controlling ischemia of myocardial tissue by electrical pulse, stimulation of the patient's nerve system, said system comprising:

• ischemia sensor means adapted to be located within the venous return system of a patient's heart for sensing a constituent of the venous return blood draining from myocardial tissue and producing an electrical output signal substantially representing chemical constituent of that blood;
• signal transforming means for receiving the electrical output signal and developing a stimulation trigger signal in respond to said electrical output signal indicative of a condition of ischemia;
• and
• means responsive to said trigger signal for applying electric stimulation pulses to said nerve system and storing said output signal.