[Spastic coronary artery. Correlation of the myocardium at risk with scintigraphy and coronary angiography]

A 52-year old patient, with symptoms of angina in the last month, was referred to undergo a SPECT myocardial perfusion. At an early stage of the exercise test, he showed electrical changes suggestive of inferior ischemia and the scintigraphy images showed intense and extensive inferolateral hypoperfusion during the effort, with complete reversibility at rest. Cardiac catheterization showed a right coronary artery without obstructive lesions. An endothelial dysfunction test with acetylcholine provoked diffuse spasm of the artery, which retrograded completely with intravenous nitroglycerin. An acute coronary syndrome may have causes other than obstructive lesions in epicardial arteries that induce myocardium at risk. The ischemic tissue can be identified by imaging techniques that thus guides the invasive studies to recognize dysfunctional coronary arteries.