Objectives This study sought to identify morphological predictors of rapid plaque progression. Background Two patterns of plaque progression have been described: slow linear progression and rapid step-wise progression. The former pattern will cause stable angina when the narrowing reaches a critical threshold, whereas the latter pattern may lead to acute coronary syndromes or sudden cardiac death. Methods Patients who underwent optical coherence tomography (OCT) imaging during the index procedure and follow-up angiography with a minimum interval of 6 months were selected. Nonculprit lesions with a diameter stenosis of ≥30% on index angiography were assessed. Lesion progression was defined as a ...