Coronary artery spasm induced by a guide wire is a very rare complication of percutaneous transluminal coronary angioplasty (PTCA). The authors describe a patient who developed coronary vasoconstriction distal to the dilated lesion during PTCA, which was refractory to intracoronary nitroglycerin and intravenous calcium antagonist injection and balloon angioplasty but responded promptly and completely to withdrawal of the guide wire from the coronary artery, suggesting that the spasm had been induced by the guide wire.