Revisiting the use of the provocative acetylcholine test in patients with chest pain and nonobstructive coronary arteries: A five-year follow-up of the AChPOL registry, with special focus on patients with MINOCA.

This study aimed to assess the angiographic characteristics, feasibility and safety of the provocative test with acetylcholine (AChT), and the influence on further treatment and prognosis of Middle European patients in 5-year follow-up, especially focusing on those with a history of myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA). The AChPOL Registry was an ongoing prospective single-center registry that included patients undergoing AChT from December 2010 to March 2013 for further diagnostic evaluation of a suspicious variant angina or coronary microvascular spasm, based on the COVADIS criteria. AChT was injected in incremental doses of 25, 50, and 75µg into the right coronary artery and 25, 50, and 100 µg into the left coronary artery, and the patients were followed up for 5 years. We enrolled 211 patients in the AChPOL Registry. Their mean age was 60.5 ± 7.8 years, with women accounting for 67.8%. The median follow-up was 56 months. AChT revealed variant angina in 99 patients (46.9%) and coronary microvascular spasm in the remaining 72 patients (34.1%). In patients with variant angina, spasm was most frequently observed in the left anterior descending artery (89.9%) and was most frequently diffuse (61.6%). In the microvascular spasm subgroup, there was a significantly higher rate of recurrent chest pain requiring hospitalization in the follow-up than in AChT negative patients. Interestingly, patients with a history of MINOCA had higher rates of MI and recurrent chest pain requiring hospitalization in the follow-up. We showed that AChT was safe in Middle European patients. In the follow-up patients with microvascular spasm and a history of MINOCA had the highest risk of MI and recurrent chest pain requiring hospitalization.