Diagnostic Agreement of CCTA and OCT in preinterventional morphometric target lesion assessment of coronary artery disease - Preliminary results of the PRECISE MORPHOLOGY Study

Background
Intravascular imaging (IVI), including optical coherence tomography (OCT), provides high-resolution assessment of lesion morphology, length and diameter (MLD), enabling comprehensive percutaneous coronary intervention (PCI) planning. IVI-guided PCI has shown improved procedural and clinical outcomes with greater stent expansion, notably lower rates of stent malapposition, edge dissections and major adverse cardiovascular events (MACCE) compared to angiography alone. Despite these advantages, IVI adoption in routine practice remains limited due to its invasive nature. In recent years, Coronary Computed Tomography Angiography (CCTA) has emerged as a non-invasive alternative. Technical advances in detector technology and image reconstruction have improved temporal and spatial resolution, suggesting its role in planning PCI. However, comparative data on diagnostic agreement of CCTA to OCT as the invasive reference standard remains scarce.

Aim
To assess the diagnostic accuracy for anatomical and interventional lesion metrics between CCTA and OCT in patients undergoing PCI.

Methods
The PRECISE MOPRHOLOGY study is a retrospective, single-center, observational study including 92 consecutive patients who underwent PCI between January 2022 and December 2024 at the University Hospital Frankfurt. Patients were eligible, if they had undergone CCTA and OCT prior to PCI. Lesion assessment was confined to culprit lesions, identified by coronary angiography. Matched measurement sites were defined using anatomical landmarks (e.g. side branches, bifurcations) to ensure spatial alignment. Key interventional parameters included minimal lumen area (MLA), minimal lumen diameter (MLD), lesion length, calcium angle, calcium thickness, calcium length. Diagnostic agreement between CCTA and OCT was analyzed using Spearman rank correlation for continuous variables and Cramér´s V for categorial variables. Statistical analysis was conducted using SPSS (Version 29, IBM Corp., Armonk, NY). 

Results
A total of 200 fiducial landmarks were assessed among the first 40 patients. Strong correlation between CCTA and OCT was observed for minimum lumen diameter (2.69 mm vs. 2.80 mm; r = 0.84; p < 0.001), maximum calcium arc (41.2° vs. 45.7°; r = 0.88; p < 0.001), and maximum calcium thickness (0.31 mm vs. 0.36 mm; r = 0.73; p < 0.001). Evaluation of lesion-level parameters using the OCT-derived MLD-(MAX) algorithm, demonstrated high concordance for interventional features. Morphological features showed strong associations: maximum calcium arc >180° (45.7% vs. 45.7%; Cramér’s V = 0.96; p < 0.001), calcium thickness >0.5 mm (82.9% vs. 85.7%; Cramér’s V = 0.90;
p < 0.001), and calcium length >5 mm (77.7% vs. 68.6%; Cramér’s V = 0.80; p < 0.001). Strong agreement was also observed for lesion length (L) (23.0 mm vs. 21.4 mm;
r = 0.69; p < 0.001) and reference vessel diameter (D) (3.1 mm vs. 3.4 mm; r = 0.72; p < 0.001).

Conclusion
Preliminary results of the PRECISE MORPHOLOGY study demonstrate a strong agreement of CCTA with OCT across key anatomical and procedural parameters. Our findings suggest that CCTA may serve as a reliable non-invasive imaging modality for CT-guided PCI, supporting preprocedural decision-making. This algorithmic assessment comprises the need for calcium modification and optimized stenting in terms of sizing and relevant side branch involvement.