Catheter-induced coronary artery spasm has been observed frequently. It is usually transient, reacts to the administration of nitroglycerin, and its distribution is generally confined to an area in proximity ot the intubated catheter. A 43-year-old woman with recurrent chest pain was found to have a rather long segment of tight proximal obstruction of the right coronary artery and experienced a myocardial infarction during coronary catheterization. Because of recurrent attacks of severe chest pain, coronary artery bypass surgery was performed which failed to result in significant improvement of her symptoms. Two repeat coronary cineangiograms seven weeks and three years after surgery revealed the proximal right coronary artery to be free of stenotic lesions or of luminal irregularities. After considering possible mechanisms of myocardial necrosis in the presence of normal coronary arteries it is concluded that myocardial necrosis can result from catheter-induced coronary artery spasm in spite of administration of nitroglycerin.