The effect of intracoronary administration of ergonovine on the contralateral coronary artery in a provocation test for the diagnosis of variant angina.

Little is known about the effects of selective intracoronary administration of ergonovine into a coronary artery on the artery on the other side. This study aimed to evaluate the effect of intracoronarily administered ergonovine on the contralateral coronary artery. From June 2011 to August 2013, coronary spasm provocation tests were performed in 85 consecutive patients using selective intracoronary administration of methylergometrine maleate (ER).The doses increased in a step-wise manner up to 60 μg for the left coronary artery (LCA) and up to 50 μg for the right coronary artery (RCA).The coronary artery diameters were measured and analysed by repeated-measures ANOVA. Twenty-four (28%) patients had a spasm-positive result. The mean diameter of the spasm segment in the contralateral artery decreased from 2.83 to 2.68 mm (5.1 ± 0.1% change, P < 0.001) in the negative spasm group and from 2.40 to 2.10 mm (11.1 ± 2.2% change, P = 0.001) in the positive spasm group. There were no serious procedure-related complications. Intracoronary administration of ER resulted in a statistically significant decrease of lumen diameter of the contralateral coronary artery. However, from the clinical perspective, the extent of the decrease was relatively small and the test may be conducted safely unless there is a significant coronary artery luminal narrowing.