IMMEDIATE RELIEF OF SPONTANEOUS CORONARY-ARTERY SPASM BY INTRACORONARY INFUSION OF AN ENDOTHELIUM-DEPENDENT VASODILATOR, SUBSTANCE-P

This report describes a 45-year-old Japanese man who had episodes of a nginal chest pain on effort. Coronary arteriography in the baseline st ate revealed subtotal occlusion in the mid-portion of the left anterio r descending coronary artery. After intracoronary infusion of an endot helium-dependent vasodilator, substance P, the subtotal occlusion was immediately abolished. We concluded that endothelium-dependent vasodil ation evoked with substance P was present at the site where coronary v asospasm occurred spontaneously in our case.