Pancoronary Plaque Characteristics in STEMI Caused by Culprit Plaque Erosion Versus Rupture: 3-Vessel OCT Study

Abstract

ObjectivesThis study sought to investigate nonculprit plaque characteristics in patients with ST-segment elevation myocardial infarction (STEMI) presenting with plaque erosion (PE) and plaque rupture (PR). Pancoronary vulnerability was considered at nonculprit sites: 1) the CLIMA (Relationship Between OCT Coronary Plaque Morphology and Clinical Outcome) study (NCT02883088) defined high-risk plaques with simultaneous presence of 4 optical coherence tomography (OCT) features (minimum lumen area <3.5 mm2; fibrous cap thickness [FCT] <75 μm; maximum lipid arc >180º; and macrophage accumulation); and 2) the presence of plaque ruptures or thin-cap fibroatheromas (TCFA). BackgroundPE is a unique clinical entity associated with better outcomes than PR. There is limited evidence regarding pancoronary plaque characteristics of patients with culprit PE versus culprit PR. MethodsBetween October 2016 and September 2018, 523 patients treated by 3-vessel OCT at the time of primary percutaneous intervention were included with 152 patients excluded from final analysis. ResultsOverall, 458 nonculprit plaques were identified in 202 STEMI patients with culprit PE; and 1,027 nonculprit plaques were identified in 321 STEMI patients with culprit PR. At least 1 CLIMA-defined OCT nonculprit high-risk plaque was seen in 11.4% of patients with culprit PE, but twice as many patients were seen with culprit PR (25.2%; p < 0.001). This proportion was also seen when individual high-risk features were analyzed separately. When patients with PE were divided by a heterogeneous substrate (fibrous or lipid-rich plaque) underlying the culprit site, the prevalence of nonculprits with FCT <75 μm, macrophages, and TCFA showed a significant gradient from PE(Fibrous) to PElipid-rich plaque (LRP) to PR. Interestingly, nonculprit rupture was rarely found in patients with culprit PE(Fibrous) (1.9%), although it was exhibited with comparable prevalence in patients with culprit PE(LRP) (16.3%) versus PR (17.8%). Culprit PE predicted decreased pancoronary vulnerability independent of conventional risk factors. ConclusionsSTEMI patients with culprit PE have a limited pancoronary vulnerability that may explain better outcomes in these patients than in STEMI patients with culprit PR.