×

Cardiac arrhythmia analysis system

  • US 4,473,078 A
  • Filed: 05/24/1982
  • Issued: 09/25/1984
  • Est. Priority Date: 05/24/1982
  • Status: Expired due to Term
First Claim
Patent Images

1. A system for monitoring the cardiac electrical activity and at least one other selected life sign of a patient, and triggering the application of appropriate therapeutic current to said patient, comprising:

  • (a) input means for receiving from said patient an electro-cardiac signal representative of said electrical activity of said patient'"'"'s heart and a second signal derived from said other selected life sign and indicative of a second criterion for the identification of selected cardiac arrhythmia;

    (b) V-fib circuit means, responsive to said electro-cardiac signal, for repetitively producing V-fib pulses at a rate greater than or equal to a first predetermined rate in response to the occurrence of ventricular fibrillation and for producing at least one V-fib pulse in response to the occurrence in sid electro-cardiac signal of a QRS complex;

    (c) QRS circuit means, responsive to said electro-cardiac signal, for producing a QRS pulse in response to the occurrence in said electro-cardiac signal of a QRS complex while producing in response to ventricular fibrillation QRS pulses at less than half the rate of V-fib pulses produced by said V-fib circuit means; and

    (d) logic means, for producing a defibrillation trigger signal, said logic means having clock means for establishing a rate measurement period, means for counting the number of QRS and V-fib pulses during said rate measurement period to determine the respective rates thereof and for producing a defibrillation request pulse if, during said rate measurement period, either the number of V-fib pulses equals or exceeds said first predetermined rate while the number of QRS pulses is less than half the V-fib pulse rate or the number of QRS pulses equals or exceeds said first predetermined rate, accumulator means responsive to said defibrillation request pulse for counting the number of said request pulses during an accumulation period, and output means, responsive to said timing means and to said second signal for producing a defibrillation trigger signal upon the occurrence of three defibrillation pulses within said accumulation period and of said second criterion for a predetermined period.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×