Diagnosis of Coronary Artery Spasm

Seminal clinical studies have shown that percutaneous coronary intervention (PCI) in patients with stable angina gives few benefits as compared with optimal medical therapy alone (Boden et al., N Engl J Med 356:1503–1516, 2007; Al-Lamee et al., Lancet 391:31–40, 2018). Therefore, making diagnosis of coronary vasomotion abnormalities regardless of obstructive or nonobstructive arterial segments has dramatically increased its clinical significance. Coronary artery spasm plays a key role in a wide range of ischemic heart diseases not only in vasospastic angina (VSA) but also in acute coronary syndrome and sudden cardiac death. It is of importance to have the precise diagnostic criteria for coronary artery spasm based on the clinically available evaluation methods. Particularly, recent studies have made substantial contributions to the development of new approaches that can predict the risk of future cardiovascular events in patients with VSA. Ample clinical evidence has been accumulated for elucidating the detailed mechanisms of coronary artery spasm in vivo. In this chapter, we will summarize recent advances in diagnostic methodology of coronary artery spasm.