Importance of provoked spasms at the sites of nonobstructive stenosis as well as at the sites of obstructive stenosis in patients with obstructive coronary arteries and coronary spasm.

Objectives: There are few reports regarding the prognosis in patients with obstructive coronary artery disease (OCAD) and vasospastic angina (VSA). This study investigated the clinical characteristics and clinical outcomes in patients with VSA and OCAD, especially regarding provoked spasm phenotypes and sites.

Methods: This was a retrospective, observational, single-center study of 403 patients with typical or atypical angina-like chest pain undergoing acetylcholine (ACH) spasm provocation testing and OCAD. An obstructed coronary artery was defined as ≥50% luminal narrowing. We defined positive epicardial spasm as ≥90% transient stenosis and usual chest symptoms or ischemic ECG changes.

Results: Among these 403 patients with OCAD, positive spasm by intracoronary ACH testing was observed in 196 patients (49%), whereas negative spasm was found in the remaining 207 patients (51%). The clinical outcomes in the patients with OCAD and provoked spasm were not different according to the provoked-spasm phenotypes. Furthermore, the clinical outcomes were unsatisfactory in the patients with spasm at the site of nonobstructive lesion alone compared with those with spasm at the site of obstructive and nonobstructive lesions.

Conclusion: We should precisely diagnose patients with OCAD who have provoked spasm by using intracoronary ACH testing and medicate the nonobstructive vessels in patients with OCAD and VSA under optimal coronary vasodilators.