[Is coronary spasmodicity unchangeable?: a study with acetylcholine or ergonovine in patients with ischemic heart...

Fluctuations of spasmodicity have been reported in affected vessels in patients with vasospastic angina, but the incidence of spasmodicity induced by pharmacologic agents on both vessels with spasm and vessels without induced spasm has not been investigated. Repeated spasm provocation tests by acetylcholine or ergonovine were performed at 13.1 +/- 9.9 month intervals (3-50 months) in 111 vessels of 50 patients with ischemic heart disease, consisting of 19 old myocardial infarction and 31 angina pectoris, who did not undergo angioplasty or have signs of advancing atherosclerosis. Spasm was defined as present when more than 90 percent stenosis was accompanied by the appearance of usual chest pain or significant electrocardiographic changes. Ninety-six vessels (86.5%), 65 without spasm and 31 with spasm, revealed coincident responses and the remaining 15 vessels contrary reacted. The coincidence rate of spasmodicity in patients at intervals of within 24 months (90.2%) was significantly higher (p < 0.05) than that at intervals of over 24 months apart (70.4%). The spasm coincidence rate was 67.3% in the vessels with provoked spasm by either the first or second tests. Only one (0.9%) out of the 111 vessels showed obvious progressive atherosclerosis during this study. The majority of vessels showed identical spasmodicity within 2 years. In conclusion, coronary spasmodicity might remain unchanged for at least 2 years despite medication with calcium channel blockers and isosorbide dinitrate.