APPARATUS FOR INFLUENCING THE SYSTEMIC BLOOD PRESSURE IN A PATIENT BY CAROTID SINUS NERVE STIMULATION

• US 3,650,277 A
• Filed: 02/17/1970
• Issued: 03/21/1972
• Est. Priority Date: 02/24/1969
• Status: Expired due to Term

• Current Assignee: Per Ake Oberg, Ulf Hakan Sjostrand
• Original Assignee: Per Ake Oberg, Ulf Hakan Sjostrand
• Inventors: Sjostrand, Ulf Hakan, Oberg, Per Ake
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/012,062
• Time in Patent Office: 763 Days
• Field of Search: 128/418,419R,421,422,423,2.5A,2.5P,2.5E,2.5M,2.5B,2.5R,2.6A
• US Class Current: 607/44
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives
• CPC Class Codes: A61N 1/36117 for treating hypertension
• CPC Class Codes: A61N 1/36564 controlled by blood pressure

Abstract

A system for reducing and controlling the blood pressure of a hypertensive patient has electrical pulse stimulation of the carotid-sinus nerves controlled by the arterial blood pressure of the patient in such a manner that the number of stimulation pulses within each heart cycle is determined by the arterial means blood pressure whereas the distribution of stimulation pulses over the heart cycle is a function of the arterial pulse wave shape with the pulse frequency being greater during the first portion of the heart cycle.

Claims

1. A system for influencing the natural biological blood pressure regulatory system in an individual, in particular for reducing and controlling the blood pressure in a hypertensive individual, by electrical pulse stimulation of an afferent nerve from a baroreceptor in the individual, said system comprising:

1. pressure sensitive transducer means adapted to be connected to the arterial system of the individual for sensing the arterial blood pressure and producing an electric output signal substantially representing the instantaneous arterial blood pressure in the individual;

2. signal transforming means receiving the transducer output signal and including (a) a first signal transforming circuit providing an output signal substantially proportional to the mean value of the transducer output signal, and (b) a second signal transforming circuit providing an output signal whose amplitude is proportional to the derivative of the transducer output signal and whose polarity corresponds to the algebraic sign of said derivative;

3. signal combining means for additively combining the output signals of said first and second signal transforming circuits and providing an output signal whose amplitude is a function of said combined signals;

4. a frequency controlled pulse generator receiving the output signal of said signal combining means as a frequency control signal for generating output pulses having a frequency proportional to the amplitude of the output signal of said signal combining means; and

5. stimulator means connecting to receive the output pulses of said pulse generator and including at least one electrode means adapted for connection to an afferent nerve from a baroreceptor in the individual.

2. A system according to claim 1, wherein said pulse generator has a minimum threshold signal value for its frequency control signal to initiate operation of the generator.

3. signal combining means for additively combining the output signals of said first and second signal transforming circuits and providing an output signal whose amplitude is a function of said combined signals;

4. a frequency controlled pulse generator connected to receiVe the output signal of said signal combining means as a frequency control signal to generate output pulses having a pulse frequency proportional to the amplitude of the output signal of said signal combining means;

said pulse generator having two outputs for said output pulses;

5. A system according to claim 1, wherein said pulse generator has a pulse frequency range up to about 300 Hz.

6. a pulse delay circuit in the one generator output connection for providing a time delay shorter than the shortest interval between two successive output pulses from the generator to prevent cross-stimulation between the right and left carotid-sinus nerves in the individual.