An Electronic Cardiac Defibrillator and Pacemaker

Abstract

There is described an instrument which has been devised to stop ventricular fibrillation and to restore rhythmical beating of the heart in standstill. The instrument provides 60‐cycle sinusoidal pulses continuously variable from 0 to 3 amperes in intensity and from 0.01 to 1.0 second in duration. A single pulse may be delivered for defibrillation, or regularly repeating pulses, from 20 to 120 per minute, may be delivered for instituting rhythmical beating of the arrested heart. The time intervals produced are quite independent of line voltage and tube changes. Suitable provision is made for the protection of the operator from accidental short circuit to ground. Clinical use of the instrument has been restricted to defibrillation, where it has proven successful.