Suspected Microvascular Coronary Spasm Diagnosed by Spasm Provocation Test with High Dose of Acetylcholine

A 71-year-old Japanese man was admitted to our hospital complaining of chest oppression on exercise, such as cycling uphill, which had continued for 9 years. We diagnosed him as having microvascular spasm according to the results of coronary angiography with an acetylcholine provocation test with a high dose (150mg) of acetylcholine administrated at a time during 20 seconds. Electrocardiographic changes during the spasm provocation test resembled that during exercise tests performed upon admission and 9 years previously. He was treated with a calcium channel blocker and partial symptom relief was obtained.