Haemodynamic characterisation of different endotypes in coronary artery vasospasm in reaction to acetylcholine

•In reaction to low-dose acetylcholine the negative and equivocal endotype has haemodynamic changes that suggest intact endothelium.•In reaction to high-dose acetylcholine the epicardial vasospasm, microvascular vasospasm and equivocal endotype have hemodynamic changes that suggest VSMC-hyperreactivity.•The data of our study shows that the equivocal endotype is a form of microvascular spasm in the presence of a normal endothelial function, and therefore these patients might benefit from treatment with anti-vasospastic medication.