RATE CONTROLLER AND CHECKER FOR A CARDIAC PACER PULSE GENERATOR MEANS

• US 3,830,242 A
• Filed: 12/11/1972
• Issued: 08/20/1974
• Est. Priority Date: 06/18/1970
• Status: Expired due to Term

• Current Assignee: Wilson Greatbatch
• Original Assignee: Wilson Greatbatch
• Inventors: Greatbatch, Wilson
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/314,170
• Time in Patent Office: 617 Days
• Field of Search: 128/2.5R,2.6R,419P,421,422,423
• US Class Current: 607/27
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/37211 Means for communicating with stimulators
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling

Abstract

A remotely-operated control for an electrical pulse generating means, such as a cardiac pacer including timing means controlling the generation of pulses and signal responsive means for resetting the timing means in response to a ventricular electrical signal. A remote, portable transmitter selectively generates a plurality, preferably about three, radio frequency signals having different envelope durations, the signal of longest duration being a continuous or carrier wave signal. Coupled to the pulse generator or pacer is a circuit responsive to the radio frequency signals which rectifies, detects and filters them to produce corresponding command signals. Two of the command signals corresponding to the relatively shorter r.f. signals can be applied to the pacer oscillator in a manner increasing or decreasing the rate of pulse generation. The command corresponding to the continuous r.f. signal can be utilized to temporarily inhibit operation of the pacer signal responsive means to check the viability of this function. In addition, this command signal can be applied to a switching means to reduce the capacitance in the timing means to in turn reduce the width of the pacer output pulses for testing the patient'"'"''"'"'s response to reduced energy pulses. In addition, this same command signal can be applied to a semi-conductor switching means for reducing the gain of the amplifier in the ventricular signal responsive means for testing the sensitivity thereof.

Claims

1. In combination with a cardiac pacer having pulse generating means, first and second output means coupled to said pulse generating means, at least one of said output means adapted to be operatively connected to a patient'"'"''"'"'s heart on or in the ventricle thereof, an oscillator portion providing output pulses at a freerunning rate and control means operatively connected to said oscillator portion and at least the ventricular one of said output means for causing generation of output pulses at a different rate determined by ventricular signals from the patient'"'"''"'"'s heart, a remotely operated control comprising:

a. a remote transmitter for selectively generating a plurality of radio frequency signals having different envelope durations;

b. means coupled to said pulse generating means and responsive to said ratio frequency signals for producing corresponding command signals;

c. said signal responsive means including means for applying one of said command signals to said oscillator portion whereby the rate of output pulse generation is changed; and

d. said signal responsive means further including means for applying another of said command signals corresonding to the radio frequency signal of longest envelope duration to said control means whereby said control means is rendered inoperative for the duration of said signal.

2. Apparatus according to claim 1 wherein said transmitter generates three signals, two of said signals being pulsating and the third being continuous, and wherein said one signal applied to said oscillator portion is a pulsating signal and said signal responsive means further includes means for applying the other of said pulsating signals to said oscillator portion, whereby the rate of generation of pacer output pulses is increased or decreased in response to generation of said one and said other pulsating signals, respectively, and the operation of said control means is stopped in response to the generation of said continuous signal.

3. In combination with an artificial cardiac pacer including pulse generating means, first and second output means coupled to said pulse generating means, at least one of said output means adapted to be operatively connected to a patient'"'"''"'"'s heart on or in the ventricle thereof, demand control means, at least the ventricular one of said output means being coupled to said demand control means for controlling the rate of pulse generation in response to ventricular signals from the patient'"'"''"'"'s heart:

a. a remote transmitter for selectively generating different first, second and third radio frequency signals, said first and second signals being pulsating signals of different envelope durations and said third signal being a continuous carrier wave signal;

b. antenna means for receiving said signal;

c. detecting means including first and second signal transmission paths, said first path being responsive to only one of said first and second signals having the shortest envelope duration and providing a trigger signal, said second path being responsive to only the other pulsating signal and said continuous signal and providing corresponding delay and inhibit signals; and

d. means for applying said trigger and delay signals to said pulse generating means for increasing and decreasing, respectively, the rate of pulse generation and means for applying said inhibit signal to said demand control means for stopping said demand control means for the duration of said inhibit signal.

4. In combination with a cardiac pacer having first and second output means, at least one of said output means adapted to be operatively connected to a patient'"'"''"'"'s heart on or in the ventricle thereof, said pacer comprising means coupled to at least the ventricular one of said outPut means including an amplifier and an oscillator for providing output pulses and timing means connected to said oscillator for causing generation of output pulses at a different rate, a remotely-operated control which comprises:

a. a remote transmitter for selectively generating at least a continuous, carrier wave radio frequency signal;

b. first semiconductor switching means connected in controlling relation to said timing means for reducing the width of output pulses from said generator;

c. second semiconductor switching means connected in controlling relation to said amplifier for reducing the gain of said amplifier;

d. signal responsive means coupled to said pulse generator for producing corresponding command signals in response to reception of said radio frequency signal;

e. said signal responsive means including means for applying the command signal generated in response to said continuous radio frequency signal in controlling relation to said first semiconductor switching means; and

f. said signal responsive means further including means for applying the command signal generated in response to said continuous radio frequency signal in controlling relation to said second semiconductor switching means.