[Comparison of the acute cardiovascular side effects of iopamidol, metrizamide and amidotrizoate after intracoronary and left ventricular injections].

The acute cardiovascular side effects of iopamidol (osmolality: 0.8 osmol/kg), metrizamide (0.6 osmol/kg), and amidotrizoate (2.1 osmol/kg) during coronary arteriography (n = 30) and left ventriculography (n = 9) have been compared in anesthetized closed-chest dogs (n = 5). The influences of these contrast media on hemodynamics, coronary circulation, ECG and physicochemical properties of coronary sinus blood were evaluated. Following intracoronary injection, iopamidol and metrizamide cause positive inotropism while amidotrizoate initially induces cardiodepression. All contrast solutions lead to marked increase of myocardial blood flow. Electrocardiographic changes are greater after amidotrizoate (P less than 0.05). A fall of cationic content in coronary sinus blood is seen after each contrast medium. Amidotrizoate leads to more decrease of potassium (P less than 0.01) and both ionized and total calcium (P less than 0.001). Increase of osmolality and hydrogen ionic content is greater after amidotrizoate than after iopamidol and metrizamide (P less than 0.01). Following left ventricular injection, marked peripheral vasodilation, as seen after amidotrizoate, does not occur after low osmolality compounds. There are no significant differences between iopamidol and metrizamide in spite of the slightly higher osmolality of the former. Thus, both contrast materials should be equivalent with respect to their acute cardiovascular side effects under clinical conditions. Advantages of low osmolality radiological contrast media are discussed.