Value of the optical coherence tomography in the diagnosis of unstable patients with non-significant coronary stenosis

Introduction and objectives: The final diagnosis of a myocardial infarction with non-obstructive coronary arteries (MINOCA) is often hard to achieve. Angiographic findings may be suggestive of the presence of unstable plaques although it is common to discharge patients without an etiologic diagnosis. The high spatial resolution provided by the optical coherence tomography (OCT) allows the detection of vulnerable and unstable coronary plaques that are prone to rupture, erosion, and thrombi which may lead to more targeted individual therapies. The objective of this study is to assess the utility of OCT when achieving an etiologic diagnosis in selected patients with MINOCA and high clinical suspicion of atherosclerotic etiology. Methods: Registry of 27 patients recruited between September 2015 and January 2020 admitted to a single tertiary hospital with acute coronary syndrome and non-significant stenosis in the coronary angiography who underwent OCT. The baseline data of the study population, the angiographic and OCT findings, treatment and follow-up information were all collected. Results: The OCT imaging showed evidence of unstable plaques (thrombus, plaque erosion or plaque rupture) in 78% of patients, which lead to an etiologic diagnosis of MINOCA. Patients were predominantly males (89%), smokers (63%), middle-aged (median 53 years old) and with a low cardiovascular risk burden. The left anterior descending coronary artery was the most frequently compromised vessel (74%) and 95% of patients ended up receiving coronary stents. The mid-term follow-up was excellent. Conclusions: In our study, OCT imaging proved to be a valuable tool to achieve an etiologic diagnosis in a large proportion of selected patients with MINOCA which, as a result could lead to more specific and individualized treatments.