Morphological predictors for low phenomenon after primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction caused by plaque rupture

Abstract

Aims Myocardial low after percutaneous coronary intervention (PCI) is associated with poor outcome. Patients with ST-segment elevation myocardial infarction (STEMI) caused by plaque rupture are at high risk for low. However, specific morphologic characteristics associated with low are unknown in this population. The aim of this study is to identify the morphological characteristics of culprit plaques associated with low in patients with STEMI caused by plaque rupture using both optical coherence tomography (OCT) and intravascular ultrasound (IVUS). Methods and results We enrolled 145 patients with STEMI who underwent both OCT and IVUS within 12 h of symptom onset. Among these patients, we excluded those with plaque erosion and calcified nodule and included 72 patients who had plaque rupture as an underlying mechanism for STEMI. Myocardial low, defined as Thrombolysis in Myocardial Infarction flow grade 0-2 and/or myocardial blush grade 0-1 after PCI, was observed in 28 patients (38.9%). Onset to recanalization time was similar between the groups with and without low. Receiver-operating curve analysis revealed OCT-derived lipid index . 3500 [area under curve (AUC) 0.77, P , 0.001] and IVUS-derived plaque burden . 81.5% (AUC 0.70, P = 0.002) were the best discriminators for myocardial low. Conclusion low occurred in nearly 40% of patients with STEMI caused by plaque rupture. Large lipid index and plaque burden were critical morphological discriminators between low and normal flow.