The importance of sodium concentration on the incidence of fibrillation during coronary arteriography in dogs.

Coronary arteriography is known to produce electrical disturbances including conduction disturbances, arrhythmias, and ventricular fibrillation. A canine model for studying ventricular fibrillation has been developed that uses relatively long injections in the right coronary artery. In experiments in 49 dogs over a five-year period, the authors have consistently observed that with low osmolality contrast media, the incidence of ventricular fibrillation becomes quite high when the formulation contains less than 3.2 mmol/L sodium. This effect seems independent of the concentration of the contrast media molecules. High concentrations of the ionic monomer diatrizoate cause fibrillation despite high sodium concentrations.