Microvascular Coronary Artery Disease

The goal of this observational study is to evaluate the diagnostic performance of angiography-derived microcirculatory indices (Angio-IMR) in assessing patients with stable angina or suspected coronary artery disease. The main questions it aims to answer are: How do the numerical values of Angio-IMR from five different software vendors change across three physiological states (resting, sub-hyperemia induced by nitroglycerin, and maximal hyperemia induced by adenosine)? Which physiological state and software algorithm provide the highest diagnostic accuracy (Area Under the Curve, AUC) for diagnosing Coronary Microvascular Disease (CMD) when compared to the gold standard wire-based IMR? Researchers will compare the Angio-IMR results calculated under the three different physiological conditions within the same patient to see how the hyperemic state impacts the performance and consistency of these non-invasive indices. Participants will: Undergo standard-of-care coronary angiography and physiological assessment using a pressure wire for index of microvascular resistance (Wire-IMR) as part of their clinical management. Have their angiographic images captured at three specific time points: at rest, after intracoronary nitroglycerin, and during adenosine-induced maximal hyperemia. Allow their de-identified imaging and clinical data to be analyzed by an independent core laboratory using five different Angio-IMR software platforms to evaluate microvascular function.

To demonstrate the feasibility and efficacy of the CS Reducer for the treatment of patients with ischaemia and non-obstructed coronary arteries (INOCA) and coronary microvascular dysfunction (CMD) and through a nested mechanistic substudy investigate the physiological responses in the coronary microcirculation responsible for changes in myocardial perfusion.

The aim of this study is to investigate the agreement and reproducibility between intravenous and intracoronary adenosine administration during invasive assessment of microvascular function. Goals of this study are: 1. Agreement and reproducibility between intravenous and intracoronary adenosine administration in the IMR (Index of microvascular resistance) value. 2. Agreement and reproducibility of FFR(fractional flow reserve), CFR (coronary flow reserve), MRR (microvascular resistance reserve), RRR (resistive reserve ratio) and reproducibility of each of these as compared with CFRabs (absolute coronary flow). 3. Time required for IMR measurements

Coronary-related myocardial ischemia can result from obstructive epicardial stenosis or non-obstructive causes including coronary microcirculatory dysfunction and vasomotor disorders. This prospective study has been created in order to provide knowledge in the field of non-obstructive coronary artery disease.