THE MECHANISM OF PRODUCTION OF VENTRICULAR FIBRILLATION IN CORONARY ANGIOGRAPHY

Abstract

The marked increase in the incidence of ventricular fibrillation which occurred when the sodium concentration in a commonly employed contrast material was reduced from 190 mEq./l. to 40 mEq./l. was investigated in an experimental model. There was a marked separation in ventricular irritability; the contrast material with 40 mEq./l. sodium causing ventricular fibrillation in 78 per cent of the animals and the compound with 190 mEq./l. causing ventricular fibrillation in only 4.5 per cent of the series. The mechanism of production of the fibrillation was examined using recordings of the monophasic action potential of the myocardium in addition to the usual electrocardiographic parameters.