BETA-ENDORPHINS DURING CORONARY ANGIOPLASTY IN PATIENTS WITH SILENT OR SYMPTOMATIC MYOCARDIAL-ISCHEMIA

Objectives. The aims of this study were to correlate beta-endorphin pl asma levels and anginal pain in patients with ischemia induced by perc utaneous transluminal coronary angioplasty and to detect eventual endo rphin variations during balloon occlusion. Background. The opioid syst em appears involved in the ab absence of pain occurring in silent myoc ardial ischemia. Methods. Beta-endorphin plasma levels were measured 2 4 h before, just before, during and after coronary angioplasty (per fo rmed on the left anterior descending artery) in 53 men with documented coronary artery disease and exercise-induced myocardial ischemia. Res ults. Group 1 (33 patients) reported symptoms; group 2 (20 patients) w as asymptomatic during angioplasty. In these patients, the prevalence of exercise induced silent ischemia was 57%. The occurrence of angina during exercise or angioplasty was related to the frequency of angina during daily life when patients were subgrouped. The severity and dist ribution of coronary artery disease did not differ between the two gro ups. During angioplasty, the number of balloon inflations and the infl ation time and pressure were similar in symptomatic and asymptomatic p atients. In each group, no short term variability of baseline beta-end orphin plasma levels was observed during 2 consecutive days. Correspon ding beta endorphin plasma levels (at baseline and during and after an gioplasty) were significantly higher in Group 2. During balloon occlus ion, the levels decreased significantly in the symptomatic group at th e onset of angina but remained stable in the asymptomatic group. Concl usions. Methodologic variables and the severity of coronary artery dis ease did not influence the presence of symptoms during angioplasty ind uced ischemia. Beta endorphin plasma levels were higher and more stabl e in patients with silent ischemia during angioplasty, suggesting that opiate levels and their variation during ischemia are associated with individual attitude to ward anginal pain.