Optical Coherence Tomography-OCT for Characterization of Non-Atherosclerotic Coronary Lesions in Acute Coronary Syndromes

Cardiovascular diseases are the main cause of death worldwide, with coronary artery disease being the predominant underlying etiology. The most prevalent coronary lesions are represented by the atherosclerotic plaques, in more than 85% of cases, but there are several other non-atherosclerotic lesions such as spontaneous coronary artery dissection and/or hematoma and spontaneous recanalization of coronary thrombus, which are less common, approximately 5% of cases, but with similar clinical manifestations as well as complications. There are insufficient data regarding the pathological mechanism, true prevalence and optimal treatment of these kind of coronary lesions. Optical coherence tomography (OCT) is an intracoronary imaging technique, developed in order to overcome the diagnostic limitations of a standard coronary angiography and has an extremely high resolution, similar to that of a usual histological evaluation of a biopsy sample, thus, OCT provides a histological-like information, but in a in vivo environment. The aim of this article is to review the current knowledge regarding non-atherosclerotic coronary lesions, with an emphasis on the importance of OCT for optimal identification, characterization of pathogenic mechanisms and optimal treatment selection.