Treatment of Coronary Spastic Angina, Particularly Medically Refractory Coronary Spasm

Coronary spasm plays an important role in the pathogenesis of variant angina as well as ischaemic heart diseases. Treatment with vasodilators such as long-acting calcium channel blockers and long-acting nitrates is generally effective in preventing coronary spasm; however, in some patients coronary spasm is refractory to standard therapy. Because of endothelial dysfunction, hyper-reactivity of coronary smooth muscle cells and other triggering factors involved in the pathogenesis of coronary spasm, drugs capable of improving these conditions may be effective in preventing medically refractory coronary spasm. In addition, a spasm provocation test is frequently performed when diagnosing coronary spasms. Although intracoronary administration of nitroglycerin generally relieves the coronary spasm that results from this test, we have encountered patients who suffered haemodynamic instability during the test. Drugs that stabilize haemodynamics and dilate the coronary artery are effective in such situations. We review treatment options for coronary spasm that are refractory to the standard oral medications and to intracoronary infusion of nitroglycerin during the spasm provocation test.