Provoked coronary spasm and acute coronary syndromes.

lthough coronary artery spasm (CAS) has been linked ith acute coronary syndromes (ACS) and vulnerable laque (1), thrombosis (2), percutaneous coronary intervenion (PCI), and stenting (3–7), very limited attention is iven to CAS in the current era. This may be related to ssumptions that the frequency of CAS is decreasing and if resent it will be eliminated with calcium antagonist (8) or itrate use. However, concerns about adverse outcomes in ypertensive and angina patients over the past decade have iminished calcium antagonist use, particularly in ACS. ong-acting nitrates, once a standard discharge order, are ot recommended discharge medications in recent ACS uidelines (9–11). Important to the perception that CAS is ecreasing is the lack of testing to detect spasm as a possible echanism for ACS when other causes are not apparent. xcept for Prinzmetal angina and cocaine use, CAS testing s either not mentioned (9,10) or is given only a IIb ecommendation (11) among patients without obstructive oronary artery disease (CAD) in recent guidelines. Thereore, among ACS patients the frequency of CAS was nknown, and it was uncertain whether it was simply a ediator of ischemia among other factors, a marker preicting adverse outcome, or both.