Contrast-medium-induced ventricular fibrillation: arrhythmogenic mechanisms and the role of antiarrhythmic drugs in dogs.
OBJECTIVE
Small electrolyte additions to a nonionic contrast medium reduce the risk of ventricular fibrillation (VF) during wedged catheter injection of a contrast medium. The current study was designed to further investigate contrast-medium-induced VF by studying the effect of pretreatment with different antiarrhythmic drugs.


METHODS
During a simulated wedged catheter situation, iohexol was injected into the anterior descending branch of the left coronary artery in five open-chest, anesthetized dogs pretreated with lidocaine, propranolol, amiodarone, almokalant, or verapamil.


RESULTS
Wedging the catheter for 60 sec did not induce VF. However, all 15 wedged catheter injections with iohexol induced VF within 28 sec (19 +/- 1 [mean +/- standard error of the mean]) despite pretreatment with antiarrhythmic drugs. Prior to VF, conduction was slowed and monophasic action potential duration lengthened in the contrast-medium-perfused myocardium, although no significant changes occurred in the control area.


CONCLUSIONS
The combination of catheter wedging and long-lasting contrast medium injection has a high risk of causing VF. Although adding a small amount of electrolytes to nonionic contrast media can reduce the risk of VF, antiarrhythmic drug therapy may not have a protective effect.
Pedersen
H K
HK
Department of Radiology, University of Tromsø, Norway.
Jacobsen
E A
EA
Mortensen
E
E
Refsum
H
H
D000200:Action Potentials / Q000187:drug effects; D000638:Amiodarone / Q000008:administration & dosage; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage*; D002404:Catheterization; D003287:Contrast Media / Q000009:adverse effects*; D017023:Coronary Angiography / Q000009:adverse effects; D003331:Coronary Vessels; D004285:Dogs; D006329:Heart Conduction System / Q000187:drug effects; D007269:Injections, Intra-Arterial; D007472:Iohexol / Q000008:administration & dosage / Q000009:adverse effects*; D008012:Lidocaine / Q000008:administration & dosage; D011292:Premedication; D011412:Propanolamines / Q000008:administration & dosage; D011433:Propranolol / Q000008:administration & dosage; D014693:Ventricular Fibrillation / Q000139:chemically induced* / Q000517:prevention & control*; D014700:Verapamil / Q000008:administration & dosage
D000889:Anti-Arrhythmia Agents; D003287:Contrast Media; D011412:Propanolamines; D007472:Iohexol; D008012:Lidocaine; D011433:Propranolol; D014700:Verapamil; C074334:almokalant; D000638:Amiodarone