Development of Electric Control of Cardiac Rhythm

Abstract

Techniques for electric control of cardiac rhythm began with the demonstration of an action current preceding each myocardial contraction. Next came direct stimulation and countershock defibrillation with electrodes placed directly on the exposed heart. Later, external electric stimulation and external countershock with electrodes on the precordium permitted emergency resuscitation from ventricular standstill and fibrillation and provided a means for stopping rapid arrhythmias. Cardiac monitors permit the prompt recognition and identification of arrhythmias; they led to the widespread growth of coronary-care units. Cardiac pacing is now undergoing extensive development and application in many new directions.