Pathophysiology and Diagnosis of Coronary Functional Abnormalities

Abstract

Approximately one-half of patients undergoing diagnostic coronary angiography for angina have no significant coronary atherosclerotic stenosis. This clinical condition has recently been described as ischaemia with non-obstructive coronary arteries (INOCA). Coronary functional abnormalities are central to the pathogenesis of INOCA, including epicardial coronary spasm and coronary microvascular dysfunction composed of a variable combination of increased vasoconstrictive reactivity and/or reduced vasodilator function. During the last decade – in INOCA patients in particular – evidence for the prognostic impact of coronary functional abnormalities has accumulated and various non-invasive and invasive diagnostic techniques have enabled the evaluation of coronary vasomotor function in a comprehensive manner. In this review, the authors briefly summarise the recent advances in the understanding of pathophysiology and diagnosis of epicardial coronary artery spasm and coronary microvascular dysfunction.

Pathophysiology of Myocardial Infarction with Non-Obstructive Coronary Artery Disease: A Contemporary Systematic Review

“… 53 However, endothelium-dependent hyperpolarization factors (mainly hydrogen peroxide) seem to be the dominant modulators of resistance arteries, acting preferentially on prearterioles and arterioles instead of NO-mediated vasodilation of large conduit arteries. 58 Endothelium-independent mechanisms of impaired vasodilation are debated, but an attenuated response to vasodilators (eg, adenosine, dipyridamole, and papaverine), and an increase in the sympathetic autonomic activity that impairs the microcirculation, have been suggested as potential mechanisms. 48 Structural alterations (eg, luminal narrowing, vascular remodeling, vascular rarefication, or extramural compression) can also explain CMD via increased coronary microvascular resistance, particularly in the context of underlying cardiomyopathies and risk factors for CAD (eg, obesity, diabetes, hypertension, aging, dyslipidemia).…”

Current Overview of Diagnostic and Treatment Strategies for Ischemia with Non-obstructive Coronary Artery Disease

“…The international diagnostic criteria for MVA were published in 2018. In addition, international guidelines have been established [34][35][36] that describe a systematic diagnostic process using invasive cardiac testing, including decreased a CFR, increased IMR, supposed MVS, and reduced blood flow velocity (contrast delay and/or thrombolysis in myocardial infarction [TIMI] frame count) [34][35][36][37][38] . MVS Mohri et al reported MVS in 1988 18) .…”

A Personalized Approach for Patients with Myocardial Infarction with Non-Obstructive Coronary Arteries

“…[ 16 ] the rate of ruptured plaques among 68 MINOCA patients was nearly 37%. The prevalence of plaque rupture could be even higher with more extensive use of higher-resolution imaging (es OCT), since other methods such as IVUS do not recognize plaque erosion [ 17 ]. Plaque erosion is the second most common cause of atherothrombosis (30–35%) [ 18 , 19 , 20 , 21 , 22 ].…”