Culprit and Non-Culprit Plaque Characteristics with Vs. Without a Healed Phenotype in Patients with Acute Myocardial Infarction Caused by Plaque Erosion ― A 3-Vessel OCT Study ―

Background: Plaque erosion can occur quietly without causing clinical symptoms, followed by a healing process resulting in healed plaque. This study aimed to assess culprit and non-culprit plaque characteristics of patients with acute myocardial infarction (AMI) caused by plaque erosion with vs. without healed phenotype at the culprit plaque using optical coherence tomography (OCT). Methods and Results: A total of 117 AMI patients caused by plaque erosion who underwent OCT imaging of 3 coronary arteries were included. Patients were divided into 2 groups based on presence or absence of a healed phenotype at the culprit site. Culprit and non-culprit plaque characteristics were compared between the 2 groups. A healed phenotype at the culprit lesion was identified in 47.9% of AMI patients caused by plaque erosion. Patients with a healed phenotype at the culprit site were more frequently with hyperlipidemia, and had a higher prevalence of macrophage infiltration, microchannels, cholesterol crystals, and calcification at the culprit lesion. Moreover, patients with a healed phenotype at the culprit site had more non-culprit plaques and more characteristics of plaque vulnerability at the non-culprit lesion. In addition, patients with a healed phenotype at the culprit site presented with more severe luminal stenosis at both the culprit and non-culprit lesion. Conclusions: A healed phenotype was identified in 47.9% of AMI patients caused by plaque erosion at the culprit site. A healed phenotype within eroded culprit plaque was associated with signs of pancoronary vulnerability and advanced atherosclerosis.