CASE REPORTS Action of Intracoronary Nitroglycerin in Refractory Coronary Artery Spasm

Coronary artery spasm usuafly reponds to sublingual nitroglycerin. This report describes four patients with variant angina and one patient with rest angina who had coronary spasm that was refractory to sublingual or i.v. nitroglycerin. In four patients, spasm occurred spontaneously and in one patient after 0.05 mg of ergonovine. In each case, 25-100 ,ug of intracoronary nitroglycerin promptly (3045 seconds) relted in reopacification of the vessel involved in spasm and resodution of evidence for ischemia. Thus, intracoronary nitroglycerin can reverse coronary artery spasm that does not respond to systemic nitroglycerin administra-