Evaluation of Treatment Response of Calcified Nodules and Nodular Calcified Lesions Using Mean Density on Coronary Computed Tomography Angiography

ABSTRACT Background Calcified nodules (CN) and nodular calcifications (NC) present significant challenges during percutaneous coronary intervention (PCI) because of their protruding morphology and high rigidity, which often result in inadequate stent expansion and suboptimal procedural outcomes. Aims This single‐center retrospective study investigated whether coronary computed tomography angiography (CCTA)‐derived mean density could predict stent expansion outcomes in CN/NC lesions identified using intravascular ultrasonography (IVUS). Methods Forty‐nine target vessels in 46 patients who underwent IVUS‐guided PCI within 1 year of CCTA were analyzed. Univariate and multivariate linear regression analyses were performed to evaluate the associations between CCTA‐derived calcification parameters, IVUS‐derived stent expansion, and stent symmetry index. Group‐based comparisons and receiver‐operating characteristic curve analyses were performed as secondary analyses to identify poor stent expansion (< 90%). Results Mean density was significantly associated with stent expansion in both univariable analysis and the multivariable mean density model adjusted for calcium arc, calcium thickness, and rotational atherectomy ( β = –0.085; 95% confidence interval [CI], –0.152 to –0.019; p = 0.013). Mean density showed a moderate inverse correlation with both stent expansion ( r = –0.415, p = 0.003) and the stent symmetry index ( r = –0.292, p = 0.042). In the secondary analyses, receiver operating characteristic curve analysis indicated that a cutoff value of 514.93 Hounsfield units yielded an area under the curve of 0.80 in non‐atherectomy cases. Conclusions These findings suggest that CCTA‐derived mean density may help guide lesion‐specific interventional strategies and serve as a valuable, noninvasive preprocedural marker for assessing the mechanical difficulty of CN/NC lesions.