- Review
26 Pages
Background/Objectives: Coronary artery calcification is a leading cause of stent failure and a strong predictor of adverse outcomes after percutaneous coronary intervention (PCI). Accurate characterization of calcium burden, depth, and morphology is central to procedural planning, targeted treatment, and better outcomes. This review summarizes the contemporary armamentarium for imaging calcified coronary lesions, from coronary angiography and computed tomography to advanced intracoronary imaging, and how it facilitates treatment. Methods: We synthesized evidence from landmark studies, validated imaging scoring systems, registries, and current guideline and consensus documents addressing the assessment and imaging-guided treatment of coronary calcification. Results: Invasive angiography shows poor diagnostic accuracy for coronary calcium detection, characterization, and quantification. Coronary CT angiography noninvasively quantifies calcium (Agatston score and three-dimensional volume) and supports preprocedural planning, although it may overestimate calcium volume. Intravascular imaging by means of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) effectively detects coronary calcium. Their use is associated with improved clinical outcomes compared with sole angiographic guidance. The addition of near-infrared spectroscopy (NIRS-IVUS) characterizes lipids within calcified plaque and high-risk calcified nodules. OCT provides the highest spatial resolution and uniquely measures calcium thickness and longitudinal calcium length, while the utilization of artificial intelligence further enhances calcium assessment. Integration of these modalities into a morphology-based, imaging-guided approach facilitates calcium detection and modification and supports PCI optimization. Conclusions: Intravascular imaging, along with coronary CT angiography, has transformed the assessment of calcified coronary lesions. Combining their strengths enables precise, lesion-specific preparation; randomized trials show that intravascular imaging guidance improves outcomes in complex PCI, while CT-guided PCI planning is emerging as a complementary strategy whose clinical value is now being tested in randomized trials.
Tomography
3 October 2026


![Appearance of coronary calcium on different imaging modalities. (A) Invasive coronary angiography of a mid-left anterior descending artery stenosis (arrow) in which no calcium is discernible. (A1) Intravascular ultrasound (IVUS) of the same lesion demonstrates 360° circumferential calcification despite the absence of angiographically visible calcium, illustrating the limited sensitivity of angiography for coronary calcium. On angiography, calcium is visible only as linear radiopacities along the vessel wall before contrast injection and only when sufficiently dense; its arc, thickness, and depth cannot be measured. (B) Coronary CT angiography: curved multiplanar reconstruction and cross-section of a heavily calcified proximal–mid-left anterior descending artery showing semicircumferential to near-concentric calcium; blooming artifact exaggerates calcium dimensions and obscures the residual lumen. The yellow box identifies the selected cross-sectional level, while the yellow reference markers indicate the corresponding lesion segment on the curved multiplanar reconstruction. (C-a) Intravascular ultrasound showing 360° circumferential calcium as a bright hyperechoic arc with posterior acoustic shadowing, which precludes measurement of calcium thickness and assessment of tissue behind the leading edge. (C-b) Intravascular ultrasound showing an eruptive calcified nodule protruding into the lumen. (D-a) Optical coherence tomography showing 360° circumferential calcium as a signal-poor, heterogeneous region with sharply delineated borders and no posterior shadowing, allowing direct measurement of calcium arc, thickness, and length. The dashed curved arrow indicates the circumferential calcium arc. (D-b) Optical coherence tomography showing a calcified nodule with an irregular surface protruding into the lumen; the dashed arrows indicate the protruding calcified nodule. All panels are reproduced from open-access publications under the Creative Commons Attribution (CC BY) license: (A) from Cui et al. [78]; (B) from Fargione et al. [64]; and (C,D) from Kałmucki et al. [79].](https://mdpi-res.com/cdn-cgi/image/width=470%2Cheight=317/https://mdpi-res.com/tomography/tomography-12-00148/article_deploy/html/images/tomography-12-00148-g001-550.jpg)




