The influence of contrast media additives upon ventricular fibrillation thresholds during coronary angiography in ischemic and normal canine hearts.

Contrast media additives that bind calcium lower the total dose necessary to induce fibrillation. The method of measuring ventricular fibrillation threshold during coronary arteriography is sensitive and allows dose comparison at volumes relevant to clinical use. We compared two commercial formulations of sodium/meglumine diatrizoate for their effects upon fibrillation threshold in normal and ischemic dog hearts. Even though the formulations differed only by their additives, Hypaque 76 was significantly less fibrillatory than Renografin 76. This was observed at two different doses and in both ischemic and non-ischemic hearts. We conclude that amounts of additives capable of binding calcium should be kept as low as possible in sodium/meglumine diatrizoate formulations that are used for coronary angiography.