Microvascular angina, INOCA, MINOCA: not as innocent as they seem

Abstract

MINOCA is a syndrome characterized by symptoms suggesting normal ischemia and coronary arteries or with stenosis less than or equal to 50%, and INOCA by the presence of ischemia without obstructive coronary artery disease. It affects women more frequently, with a prevalence of 3.5 to 40%. It is multifactorial and may correspond to a) epicardial coronary abnormalities (atherosclerotic plaque rupture, ulceration, fissures, erosion or coronary dissection with non-obstructive coronary artery disease or without coronary heart disease): type 1 infarction; b) Imbalance between oxygen supply and demand (such as spasm and coronary embolism, type 2 infarction); c) Coronary endothelial dysfunction (epicardial coronary spasm or microvascular dysfunction, type 2 infarction), and d) Secondary to myocardial disorders without involvement of coronary arteries (myocarditis, cardiomyopathy, Takotsubo cardiomyopathy). Diagnosis is based on the clinical and ECG findings and elevated troponin values. Imaging has a determining role; thus, an angiography is necessary to start the diagnosis of accuracy and establish the cause, and to perform an evaluation of the coronary wall with IVUS or OCT, and when the lesions are moderate in many cases an FFR is necessary. PET provides a highly reliable evaluation of coronary microcirculation, myocardial perfusion, coronary blood flow and left ventricular function; but its high cost makes it not possible to use it routinely in our environment. Treatment should be aimed at correcting the cause; if there is ≤50% obstruction with evidence of atherosclerotic plaque rupture or erosion, the treatment will be that of an ACS.