Abstract
Aim: Calcified nodules (CNs) represent a high-risk morphological subset of coronary atherosclerosis, categorized into eruptive and non-eruptive subtypes. Although previous studies have noted morphological differences, the interplay between plaque composition, spatial distribution, and eruption biomechanics across clinical presentations remains incompletely understood.
Methods: We performed a multimodality intravascular imaging study using optical coherence tomography (OCT) and near-infrared spectroscopy–intravascular ultrasound (NIRS-IVUS) in patients with coronary CNs across chronic and acute coronary syndromes. We assessed calcium architecture, lipid content (maximum lipid core burden index within 4-mm, maxLCBI4mm), and anatomical distribution to evaluate factors associated with the eruptive phenotype.
Results: We identified 70 CNs (31 eruptive, 39 non-eruptive) in 64 patients. Eruptive CNs exhibited greater calcium angles, increased thickness, longer longitudinal extent, and significantly higher maxLCBI4mm compared to non-eruptive CNs. Topographically, eruptive CNs preferentially clustered within high-biomechanical-stress regions (mid-right coronary artery and proximal left anterior descending artery), whereas non-eruptive CNs were homogeneously distributed. A multivariable analysis confirmed hemodialysis, mid-RCA location, and elevated maxLCBI4mm as independent factors associated with the eruptive phenotype.
Conclusion: Eruptive CNs reflect a potential “two-hit” mechanism, wherein a vulnerable substrate (heavily calcified, lipid-rich plaque) interacts with a permissive mechanical environment (vascular flexion/hinge points) to promote eruption. Integrating plaque composition with anatomical location enhances the phenotypic characterization of calcified coronary disease.
