A double-blind, randomized study of the effect of immediate intravenous nitroglycerin on the incidence of postprocedural chest pain and minor myocardial necrosis after elective coronary stenting

Background Anginal chest pain without creatine kinase (CK) elevation is fre quently observed in the first hours after coronary stenting. Possible cause s of ischemic episodes are microembolism, side branch occlusion, coronary v asospasm, and disturbances of microvascular circulation. In a prospective, double-blind, randomized trial, we tested the effect of intravenous nitrogl ycerin on the incidence of angina and minor myocardial necrosis (MMN), as d etected by cardiac troponin I increase, after elective coronary stenting. Methods and Results One hundred patients were randomly assigned to intraven ous nitroglycerin (group A: n = 50, goal dose 100 mu g/min) or placebo (gro up B: n = 50, NaCl 0.9%) during 12 hours after stenting. Patients with acut e myocardial infarction, known intolerance to nitrates, and hemodynamic ins tability during angioplasty were excluded. The 2 groups were comparable in respect to baseline and interventional variables, except for age (group A: 60 +/- 9 years, group B: 56 +/- 10 years; P = .04). The incidence of chest pain was not influenced by nitroglycerin (group A: 18%, group B: 22%; P = n ot significant). However, the occurrence of MMN was significantly reduced b y nitroglycerin (group A: 5%, group B: 19%, P = .036). A rise in CK with si gnificant CK-MB fraction was observed in only 2 patients in group B (both l ess than twice upper limit). Only 4 of the 10 patients with MMN also had ch est pain. Conclusions Routine use of intravenous nitroglycerin after coronary stentin g significantly reduced the occurrence of minor myocardial necrosis. Howeve r, the incidence of postprocedural chest pain remained unchanged.