Action of intracoronary nitroglycerin in refractory coronary artery spasm.

Abstract

Coronary artery spasm usually responds to sublingual nitroglycerin. Patients [4] with variant angina and 1 patient with rest angina who had coronary spasm that was refractory to sublingual or i.v. nitroglycerin are described. In 4 patients, spasm occurred spontaneously and in 1 patient, after 0.05 mg of ergonovine. In each case, 25-100 .mu.g of intracoronary nitroglycerin promptly (30-45 s) resulted in reopacification of the vessel involved in spasm and resolution of evidence for ischemia. Intracoronary nitroglycerin can reverse coronary artery spasm that does not respond to systemic nitroglycerin administration.