Protective effects of repetitive injections of radiographic contrast media on the subsequent tolerance to ischemia in the isolated rat heart.
OBJECTIVE
Despite detailed knowledge of the effects of X-ray contrast media on cardiac function, no studies have examined the effect of contrast media injections on the subsequent tolerance to ischemia in the heart.


METHODS
Isolated perfused rat hearts were exposed to repetitive injections of iohexol, iodixanol, or ioxaglate before 30 min of global ischemia and 120 min of reperfusion. These groups were compared with control (no pretreatment) and ischemic preconditioning known to reduce infarct size. Physiologic variables and infarct size were measured


RESULTS
Pretreatment with iodixanol reduced infarct size significantly compared with control and thus afforded protection against ischemia. Injections with iohexol and ioxaglate reduced infarct size, although not significantly, compared with control.


CONCLUSIONS
Pretreatment of the isolated rat heart with commonly used contrast media enhances the cardiac tolerance to subsequent ischemia. The mechanism behind this protective effect could not be determined, but could involve stretching of the heart and/or generation of nitric oxide.
Department of Physiology and Biomedical Engineering, Norwegian University of Science and Technology, Medisinsk Teknisk Senter, Trondheim. Geir.Falck@medisin.ntnu.no
G
G
Falck
M
M
Bruvold
J
J
Schjøtt
P
P
Jynge
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D003287:Contrast Media / Q000008:administration & dosage*; D017023:Coronary Angiography / Q000379:methods; D003326:Coronary Circulation / Q000187:drug effects*; D003331:Coronary Vessels / Q000187:drug effects* / Q000473:pathology; D066298:In Vitro Techniques; D007269:Injections, Intra-Arterial; D007472:Iohexol / Q000008:administration & dosage; D007485:Ioxaglic Acid / Q000008:administration & dosage; D019157:Ischemic Preconditioning, Myocardial / Q000379:methods*; D008297:Male; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley
D003287:Contrast Media; D007472:Iohexol; D007485:Ioxaglic Acid