THE EFFECT OF THE TEMPERATURE OF CONTRAST-MEDIA ON CARDIAC ELECTROPHYSIOLOGY AND HEMODYNAMICS DURING CORONARY ARTERIOGRAPHY

RATIONALE AND OBJECTIVES. The authors assess the effect of preheating ionic and nonionic contrast media on regional electrophysiologic and/or hemodynamic side effects during coronary arteriography. METHODS. The authors injected 6 mL of nonionic (iohexol) and ionic (ioxaglate) low-osmolality contrast media and NaCl 0.9% twice, at 20-degrees-C and 37-degrees-C, into the left coronary artery in eight open-chest dogs. To study regional electrophysiologic effects, the authors measured monophasic action potential duration (MAPD) using an epicardial suction electrode placed in the contrast-perfused area. Hemodynamic effects were studied by recording left ventricular systolic pressure (LVSP), mean aortic pressure, LV end diastolic pressure (LVEDP), LV dP/dt(max) and cardiac output. RESULTS. Ioxaglate and iohexol prolonged MAPD more at 20-degrees-C than at 37-degrees-C. NaCl 0.9% prolonged MAPD only when injected at 20-degrees-C. The temperature of iohexol did not significantly influence LV pressures (LVPs) or LV dP/dt(max). Ioxaglate increased LVEDP and decreased LV dP/dt(max) more at 20-degrees-C than at 37-degrees-C 10 seconds after injection. CONCLUSIONS. In dogs, contrast media, preheated to body temperature before selective injection during coronary arteriography, reduced dispersion of repolarization and reduced the risk of serious cardiovascular complications.