Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA): Focus on Coronary Microvascular Dysfunction and Genetic Susceptibility

Abstract

Among the most common causes of death worldwide, ischemic heart disease (IHD) is recognized to rank first. Even if atherosclerotic disease of the epicardial arteries is known as the leading cause of IHD, the presence of myocardial infarction with non-obstructive coronary artery disease (MINOCA) is increasingly recognized. Notwithstanding the increasing interest, MINOCA remains a puzzling clinical entity that can be classified by distinguishing different underlying mechanisms, which can be divided into atherosclerotic and non-atherosclerotic. In particular, coronary microvascular dysfunction (CMD), classifiable in non-atherosclerotic mechanisms, is a leading factor for the pathophysiology and prognosis of patients with MINOCA. Genetic susceptibility may have a role in primum movens in CMD. However, few results have been obtained for understanding the genetic mechanisms underlying CMD. Future studies are essential in order to find a deeper understanding of the role of multiple genetic variants in the genesis of microcirculation dysfunction. Progress in research would allow early identification of high-risk patients and the development of pharmacological, patient-tailored strategies. The aim of this review is to revise the pathophysiology and underlying mechanisms of MINOCA, focusing on CMD and actual knowledge about genetic predisposition to it.

Prognostic Assessment of HLM Score in Heart Failure Due to Ischemic Heart Disease: A Pilot Study

“…This impedes the oxidation of the augmented lipid load, contributing to contractile dysfunction and the initiation of apoptosis [ 31 ]. Furthermore, the inadequacy of coronary circulation to meet cardiomyocytes’ metabolic demand, attributed to the imbalance of mechanisms involved in coronary blood flow regulation, such as ion channel dysfunction, results in coronary microvascular dysfunction [ 32 , 33 ]. This dysfunction leads to the onset of hypoxia, fibrosis, and tissue necrosis, potentially causing a decline in myocardial function.…”

Transient Left Ventricular Dysfunction from Cardiomyopathies to Myocardial Viability: When and Why Cardiac Function Recovers

“…Non-atherosclerotic causes of MINOCA are diverse, including coronary artery spasms, microvascular dysfunction, thrombosis or embolism, artery dissection, and mismatches in oxygen supply and demand [76]. Coronary spasms occur due to hypersensitive muscle in the vessels, reacting to internal or external substances like cocaine [77].…”

“…Studies indicate that more than 25% of MINOCA patients tested show spasm upon special testing [78]. Microvascular dysfunction is crucial in MINOCA since it accounts for about 70% of coronary resistance, which is hard to detect through angiography as this method primarily reveals larger artery issues [76].…”

Spontaneous Coronary Artery Dissection in Clinical Practice: Pathophysiology and Therapeutic Approaches

“…The presence of cardiac symptoms with the elevation of a cardiac biomarker is diagnostic of an acute myocardial injury (AMI), considering the contemporary fourth universal definition of myocardial infarction [2]. After the exclusion of coronary plaques ≥50% in any major epicardial vessel via angiography and an alternative diagnosis has been ruled out (especially pulmonary embolism and myocarditis), MINOCA is identified [2,3].…”

“…Non-atherosclerotic mechanisms mainly include epicardial coronary vasospasm, coronary microvascular dysfunction, coronary embolism/thrombosis, spontaneous coronary artery dissection (SCAD), and supply/demand mismatch. SCAD causes MINOCA due to vessel luminal obstruction, even in cases where the obstruction may not be evident, especially when occurring at distal epicardial vessels [3].…”