Effects of iopentol, iohexol and metrizoate on the contractility of the isolated rabbit heart.

Fifteen isolated rabbit hearts were perfused with Krebs' solution according to the Langendorff technique. Before, during, and after perfusion of the heart with iopentol, iohexol and metrizoate at doses 1 ml, 2 ml and 4 ml (350 mg I/ml), ECG and left ventricular contractile force were registered. The contractile force was measured with a strain gauge sutured to the wall of the left ventricle. At each dose 12 perfusions were made. At each dose iohexol and iopentol produced a smaller decrease in contractile force than metrizoate (p less than 0.001). There was no difference in effect on contractile force between iohexol and iopentol.