Clinical Limitations of Vasoreactivity Testing as a Diagnostic Tool in Patients with Vasospastic Angina

The Japanese Circulation Society guidelines recommend a class I vasoreactivity test to diagnose patients with vasospastic angina (VSA). However, the acetylcholine or ergonovine test has been established as the gold standard for variant angina (VA). The sensitivity and specificity of intracoronary vasoreactivity testing in patients with VA were acceptable. Cardiologists have employed these vasoreactivity tests to conveniently diagnose the presence of coronary spasms in patients with all VSA. The majority of VSAs may have lower disease activity than VA cases. We have summarized the usefulness of spasm provocation tests in patients with VA and VSA. A positive-provoked spasm diagnosed by standard vasoreactivity testing may indicate a disease state similar to that of VA, whereas a negative-provoked spasm after standard vasoreactivity testing may indicate a lower disease state than that of VA. Cardiologists should reconsider the limited usefulness of vasoreactivity testing when diagnosing the presence of coronary spasms in all VSAs, but not VA.