Objectives. This study sought to determine whether the location of coronary spastic activity may change over time in patients with persistent variant angina.Background. Although electrocardiographic studies have provided indirect evidence to indicate that the location of ischemia may change in patients with variant angina, it has not been tested by quantitative angiography whether the location of vasospastic activity may change over time.Methods. Paired ergonovine provocation tests and coronary angiography were performed at a mean (-+SD) interval of 43 +-13 months apart in patients with persistent symptoms of vasospastic angina in the absence of significant atherosclerosis. A total of 87 spastic and nonspastic segments of 87 major vessels in 29 patients were analyzed by quantitative angiography at baseline, after the administration of ergonovine and after isosorbide dinitrate at the initial and follow-up tests.Results. Although many clinical studies (4,6,8,9,15,21) have shown that coronary spasm frequently occurs at sites of advanced atherosclerosis, Conti et al. (7) suggested that the presence of significant atherosclerosis may reduce the role of vasospasm in ischemic attacks. To determine the long-term role of vasospastic activity and its variation in location, we repeated ergonovine provocation tests in patients without advanced atherosclerosis but with persistent symptoms of variant angina at an average interval of 43 months apart, using a computer-based quantitative coronary angiographic analysis system (CAAS II).
MethodsCriteria of vasospastic angina. The following criteria of vasospastic angina were used: 1) chest pain at rest associated with ST segment changes >0.2 mV on the ECG; 2) pain relief immediately after administration of nitroglycerin; 3) no subsequent evidence of myocardial infarction; 4) ergonovineprovoked coronary spasm associated with chest pain and ischemic ECG changes. Coronary spasm was defined as 1) a transient total or nearly total occlusion reversible with isosorbide dinitrate, or 2) a transient, significant (>50%) narrowing reversible with isosorbide dinitrate in normal or nearly normal segments (24-26). We used the ergonovine provocation test because it has been found (27-29) to have a high sensitivity and ,©1995 hy lhc American (',~llt g¢ ~,! ( ur&,+,~ 0735-1097/95/$9.50 0735-1097(95)00398-N