Helium in the Prevention of Ventricular Fibrillation

¹ Cardiopulmonary Surgical Section, Veterans Administration Hospital, Hines, Illinois and the Department of Surgery, Loyola University Stritch School of Medicine, Hines, Illionis

The influence of helium upon ventricular fibrillation after acute myocardial infarction has been investigated in 27 dogs. A gas mixture containing 50 percent air, 30 percent oxygen and 20 percent helium prevented the occurrence of ventricular fibrillation in 15 dogs, which had the left circumflex coronary artery occluded acutely. In another group ventilated with 20 percent oxygen and 80 percent helium the incidence of ventricular fibrillation was eight percent. Both groups were compared with a control group (22 dogs) ventilated with room air and ventricular fibrillation occurred in 54 percent of the animals. The mechanism of the protective effect remains to be established. The possible action of helium to increase the blood supply to the ischemic area has been discussed.