[Shock during spasm provocation tests with acetylcholine: four case reports].

Four patients suffered shock during the spasm provocation test with acetylcholine. An 84-year-old man with acute coronary syndrome was treated with stent implantation in the mid left anterior descending artery. Before discharge, acetylcholine test demonstrated coronary spasm in both the proximal left anterior descending artery and proximal left circumflex artery. A 61-year-old woman was admitted to the hospital because of recurrent rest and effort chest pain. Coronary arteriography showed no significant stenosis but shock was observed by intracoronary injection of acetylcholine due to diffuse severe coronary vasospasm in the proximal left anterior descending artery and left circumflex artery. Shock occurred in 4 of 1110 (0.36%) consecutive acetylcholine tests. Coronary spasm was gradually relieved and recovered from shock by the intraarterial administration of small amounts of norepinephrine and isosorbide dinitrate. Although the acetylcholine spasm provocation test is safe and reliable, care is required even during a selective procedure.