A 49-year-old woman was admitted to our hospital because of frequent postprandial esophageal angina. After successful pyloric plasty, chest oppression lasting 5 to 15 min developed postprandially as well as symptoms of dumping syndrome. Electrocardiography showed ST-segment elevation in the II, III, aVf and precordial leads (V2 to V6). Finally, giant positive T waves and U waves were uniquely noted in the V1 to V5 leads. Intracoronary administration of acetylcholine (20 micrograms) provoked severe diffuse spasm in both right and left coronary arteries, chest pain and ST elevation. The conventional treatment for vasospastic angina, such as Ca2+ antagonists, nitrates and K channel opener, achieved no response. However, the combination with serotonergic receptor blockade reduced anginal attack. These findings suggest that the spastic angina in this case was partly caused by serotonin.