(A) Coronary angiogram of a 48-year-old woman with rest angina in the early morning. Seven days later, coronary angiography shows no significant stenosis in either coronary artery. After injection of ergonovine maleate into the right coronary artery, total spasm was provoked (left), with severe chest pain and electrocardiographic changes. After isosorbide dinitrate was injected, the spasm was completely resolved (right). (B) Series of rest tetrofosmin perfusion and BMIPP single-photon emission computed tomography images. No significant abnormal perfusion is observed on the rest tetrofosmin images at the time of hospital admission. However, the BMIPP images show reduced uptake in the inferior region on the next day. Reproduced with permission from Kawai Y, Tsukamoto E, Nozaki Y, Morita K, Sakurai M, Tamaki N. Significance of reduced uptake of iodinated fatty acid analogue for the evaluation of patients with acute chest pain. J Am Coll Cardiol. Dec 2001;38(7):1888–1894.