Externally-inhibited tachycardia control pacer

• US 4,488,554 A
• Filed: 07/26/1982
• Issued: 12/18/1984
• Est. Priority Date: 03/19/1981
• Status: Expired due to Term

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Telectronics Incorporated
• Inventors: Swift, Stephen J., Nappholz, Tibor A.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US06/402,204
• Time in Patent Office: 876 Days
• Field of Search: 128/702-706, 128/419 PG
• US Class Current: 607/14
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/37 Monitoring; Protecting
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile

Abstract

A tachycardia control pacer for which placing a magnet over the patient'"'"'s chest results in the generation of two pulses, the time separation between which is an indication of the battery potential. Application of the magnet in this way also holds the device off, after the two pulses are generated, so that if the device is causing him discomfort the patient can temporarily disable it until the physician can program it off. Application of a magnet to the patient'"'"'s chest, or programming of the device, resets two scanned inter-pulse time intervals to the values programmed by the physician. The next scanning begins with the programmed time values. In this way the physician, after inducing tachycardia, can verify the programmed time parameters rapidly by observing the patient'"'"'s ECG waveform, without having to wait several minutes until scanning from the previously retained successful values would otherwise progress to the programmed values.

Claims

1. A tachycardia control pacer comprising means for confirming a tachycardia episode, means for timing a time delay, means responsive to said confirming means for generating at least one heart-stimulating pulse at the end of said time delay following the last heartbeat to terminate said tachycardia episode, externally-controlled means operable by external means independent of said pulse generating means operation for inhibiting operation of said pulse generating means only for as long as said external means exercises control thereover, means for causing said timing means to scan said time delay during successive cycles of operation of said pulse generating means following operation of said confirming means, program control means for controlling a range through which said time delay is scanned in accordance with externally-generating signals which represent a specific time delay in said range, and means responsive to operation of said program control means for causing the next time delay of said timing means to be dependent upon only the time delay last represented by externally-generated signals and independent of the last time delay controlled by said scan causing means.

2. A tachycardia control pacer in accordance with claim 1 wherein said externally-controlled means includes a magnetically-operated switch and is operated for as long as an external magnet continues to be held in the vicinity of the pacer.

3. A tachycardia control pacer in accordance with claim 2 wherein said program control means further includes means for selectively enabling and disabling the generation of heart-stimulating pulses in accordance with externally-generated signals, and wherein said inhibiting means inhibits the generation of pulses temporarily until a disablement by said program control means can be effected.

4. A tachycardia control pacer in accordance with claim 3 wherein said program control means includes means for causing the pacer to generate at least one pulse at a time to induce tachycardia following which the next time delay is dependent upon only the time delay last represented by externally-generated signals.

5. A tachycardia control pacer in accordance with claim 1 wherein said program control means further includes means for selectively enabling and disabling the generation of heart-stimulating pulses in accordance with externally-generated signals, and wherein said inhibiting means inhibits the generation of pulses temporarily until a disablement by said program control means can be effected.

6. A tachycardia control pacer in accordance with claim 5 wherein said program control means includes means for causing the pacer to generate at least one pulse at a time to induce tachycardia following which the next time delay is dependent upon only the time delay last represented by externally-generated signals.

7. A tachycardia control pacer in accordance with claim 1 wherein said program control means includes means for causing the pacer to generate at least one pulse at a time to induce tachycardia following which the next time delay is dependent upon only the time delay last represented by externally-generated signals.