Intraventricular Conduction During Coronary Arteriography in Patients with Pre-existing Conduction Abnormalities

Conduction disturbances have been reported to occur during coronary angiography. We evaluated the response of the intraventricular conduction system during coronary angiography utilizing Renografin-76 in 22 patients. None had hemodynamically significant coronary arterial lesions. Ten had normal intraventricular conduction. Twelve were abnormal: 6 patients had right bundle branch block, 3 patients had right bundle branch block and left anterior hemiblock, and 3 patients had left bundle branch block. Several leads of electrocardiogram were simultaneously recorded with a bipolar eavitary His bundle electrogram before, control, and during right and left coronary angiography. All patients received Atropine prior to coronary angiography. The following measurements were analyzed: heart rate (HR), atrium to His bundle (AH) interval, and His bundle to ventricle (HV) interval. Right coronary arteriography produced a significant increase in atrium to His bundle interval indicating the depressing effect of contrast agent in the atrioventricular node. However, no change in intraventricular conduction time (His bundle to ventricle interval) was observed in either the normal or abnormal patients. These results indicate that Renografin-76 does not affect the intraventricular conduction system, even in the presence of intraventricular conduction delay. Placement of temporary pacemaker in patients with intraventricular conduction delay during coronary angiography does not seem necessary.