[Experimental electric and biochemical data on ventricular fibrillation due to ischemia]

The author presents the results of prolonged research into ventricular fibrillation during myocardial ischaemia, both from the electrocardiographic and biochemical standpoints. - He emphasises the successive tonic and atonic features of VF due to ischaemia, and the difference between the fibrillation in an ischaemic area and in a control area. The most original concept is that there is often a difference between the onset of VF in an ischaemic zone and in a control zone. This study has been carried out with both acute and progressive ischaemia. - The biochemical studies were carried out on blood samples taken from the origin of the coronary arteries, the coronary veins, and from the saphenous veins. An important finding was the definite increase in the potassium level of the coronary venous blood in proportion to the degree of ischaemia; the sodium level showed little change, and if anything tended to fall. But the most important and distinctive finding was that at the onset of VF the sodium and potassium concentrations in the coronary venous blood suddenly increase. As the VF continues, there is a progressive increase in lactic acid and a fall in pH, which is maximal at the onset of the VF. These findings are valid under normothermic conditions, and when there is no extracorporeal circulation. - The physiopathological and practical implications of these facts are discussed.