OCT Findings in MINOCA

Abstract

Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is a working diagnosis for patients presenting with acute myocardial infarction without obstructive coronary artery disease on coronary angiography. It is a heterogenous entity with a number of possible etiologies that can be determined through the use of appropriate diagnostic algorithms. Common causes of a MINOCA may include plaque disruption, spontaneous coronary artery dissection, coronary artery spasm, and coronary thromboembolism. Optical coherence tomography (OCT) is an intravascular imaging modality which allows the differentiation of coronary tissue morphological characteristics including the identification of thin cap fibroatheroma and the differentiation between plaque rupture or erosion, due to its high resolution. In this narrative review we will discuss the role of OCT in patients presenting with MINOCA. In this group of patients OCT has been shown to reveal abnormal findings in almost half of the cases. Moreover, combining OCT with cardiac magnetic resonance (CMR) was shown to allow the identification of most of the underlying mechanisms of MINOCA. Hence, it is recommended that both OCT and CMR can be used in patients with a working diagnosis of MINOCA. Well-designed prospective studies are needed in order to gain a better understanding of this condition and to provide optimal management while reducing morbidity and mortality in that subset patients.

Keywords: acute myocardial infarction; cardiovascular disease; intravascular imaging.

Figure 1

Optical coherence tomography images from patients with MINOCA. Spontaneous dissection (a,b), plaque erosion (c), plaque rupture (d), thin-cap fibroatheroma (e), small white thrombi (f), and calcified nodule erosion (g,h). Figures from authors’ library.

Figure 2

Proposed approach to myocardial infarction with non-obstructive coronary artery disease diagnosis. Flowchart is explained in the text. ACS indicates acute coronary syndrome; ARDS, acute respiratory distress syndrome; CMR, cardiac magnetic resonance; ESRD, end stage renal disease; MINOCA, myocardial infarction with non-obstructive coronary artery disease; OCT, optical coherence tomography; SCAD, spontaneous coronary artery dissection; and TEE, trans esophageal echocardiography.