1940s

If ventricular fibrillation develops in hearts that are relatively normal, especially during operations, defibrillation may be life saving. During the period before regular rhythm is restored the heart must be exposed and rhythmically massaged in the interval. The method consists of the injection of 5cc. of 2 per cent procaine hydrochloride into the right side of the heart followed by a brief period of cardiac massage to distribute the drug throughout the myocardial bed. The heart is then placed between two large electrodes and ordinary 110 volt alternating current with 1.5 amperes is momentarily impressed through the heart between the electrodes. Usually a series of such shocks is necessary to accomplish defibrillation. If the treatment is successful, the ventricles cease fibrillating and remain in standstill momentarily before a supraventricular rhythm is established. Massage is again continued until the vigor of the heart beat is sufficient to empty the cardiac cavities of blood. Defibrillation of the human ventricles at the operating table has been performed five times at this hospital in the past, but all patients have subsequently died without regaining consciousness. We are reporting the first case with complete recovery after prolonged ventricular fibrillation. We present it with the hope that, following Beck's suggestion, operating rooms will be equipped to handle cases of sudden ventricular fibrillation and that personnel will be trained in the method. Speed and precision in the technique are important.

A boy aged 14, was admitted to Dr. Claude Beck's service of this hospital for sternal resection because of severe congenital funnel chest. During the closure of the wound in the chest, the pulse suddenly stopped and blood pressure sounds could not be heard. The patient was apparently dead. The wound was reopened and cardiac massage immediately was initiated. The mechanical respirator was attached to the intratracheal tube and cardiac massage continuously given for the next thirty-five minutes, at the end of which time the electrocardiogram was characteristic of ventricular fibrillation. Another record ten minutes later was recorded just prior to the first electric shock applied directly to the heart. This record, as well as the tracing recorded immediately after the first shock, also showed ventricular fibrillation. Since the first shock was unsuccessful, procaine hydrochloride was injected into the right auricle, the heart massaged and a second series of shocks given. The heart then was in standstill.

Almost immediately, however, feeble, regular and fairly rapid cardiac contractions were seen, but massage was continued for five more minutes, at which time it was obvious that contractions were coordinated and fairly vigorous, though still fast. An electrocardiogram taken at this time revealed a supraventricular tachycardia at a rate of 175. From this point on the heart gradually increased in vigor and brachial sounds were heard at 50 mm. of mercury.

Beck CS, Pritchard WH, Feil HS. Ventricular Fibrillation of Long Duration Abolished by Electric Shock. J Amer Med Assoc. 1947; 135(15):985-986.

Geddes LA, Hamlin R. The First Human Heart Defibrillator. Amer J Cardiol 1983; 52:403-405

All photos of the Beck Defibrillator are courtesy of The Smithsonian Institution

In 1940 Wiggers and Wegria established beyond doubt the existence of the ventricular vulnerable period by elegant experiments that confirmed previous less striking observations.

A. "Repeated tests on seventeen different dogs demonstated consistently that stimuli falling during the rise of interventricular pressure are without effect, that those applied during the summit at various intervals up to about 0.06 second before the end of contraction, marked by the incisura, produce either a small premature contraction early in following diastole, or ventricular fibrillation, and that those given during isometric relaxation or subsequent diastole cause premature contractions only. "

B. "A considerable portion of late systole constitutes a (vulnerable period), during which alone stimuli are effective in inducing ventricular fibrillation. This corresponds roughly to the T wave of a standard electrocardiogram, although in our experience great variability exists in the relation of this wave to the end of systole."

Wiggers CJ, Wegria R, Pinera B.The effects of myocadial ischaemia on the fibrillation threshold.
Am JPhysiol 1940; 131:309-316

A series of 56 foreign bodies that have been removed from within or on the heart is discussed. Thirteen of these were removed from the chambers of the heart in our series of 134 patients who have had foreign bodies removed, there have been no deaths and the men are clinically well." Foreign bodies, shrapnel, bullets and other deterius were first routinely removed from within about the heart during the Second World War. At war’s end the heart, previously considered inviolate and too dangerous to be operated upon, was demonstrated to be approachable. The intellectual climate changed and led to the cardiac procedures of the post-war era.

Zoll later wrote: " I became interested in electrical stimulation of the heart shortly after World War II, after I had observed much of the pioneering cardiac surgery done by Dr. Dwight Harken for the removal of foreign bodies in and around the heart. The heart appeared, indeed, to be a very sensitive organ and responded readily with ventricular contractions to stimuli; arousal from ventricular standstill by appropriate stimulation should, therefore, not be difficult."