Safety, Feasibility, and Diagnostic Yield of Invasive Coronary Function Testing

Importance: Patients with angina and no obstructive coronary artery disease frequently have coronary vasomotor dysfunction as underlying pathophysiological mechanism, comprising epicardial spasm, microvascular spasm, and/or microcirculatory dysfunction. These endotypes can be diagnosed by invasive coronary function testing which has previously shown to be safe in tertiary and expert centers. Objective: To determine the prevalence of vasomotor dysfunction in patients with angina and no obstructive coronary artery disease who were clinically referred for a coronary function test (CFT); and assess safety and feasibility of a CFT. Design, Setting, and Participants: This quality improvement study was performed using the Netherlands Registry of Invasive Coronary Vasomotor Function Testing (NL-CFT), a prospective, observational registry, in 15 participating hospitals (2 tertiary and 13 nontertiary). Patients with angina and no obstructive coronary artery disease who were referred for a clinically indicated CFT between December 2020 and January 2024 were included. Main Outcomes and Measures: A complete CFT consisted of acetylcholine spasm provocation testing and assessment of microcirculatory function. Prevalence of different endotypes based on test results and overall safety were assessed. Results: Among a total of 1207 patients included, 978 (81%) were female; and the mean (SD) age was 60 (10) years. The prevalence of coronary vasomotor dysfunction was very high (78%). There were 11 (0.9%) major and 10 (0.8%) minor complications reported. Of them, 3 major and all minor were definitely related to the coronary function test. No procedural death, myocardial infarction, or stroke was observed. No differences were found in the occurrence of complications between tertiary and nontertiary centers. Conclusions and Relevance: This study found that a CFT was feasible and safe to perform in both tertiary and nontertiary centers with a high diagnostic yield.