https://doi.org/10.1007/s00392-024-02526-y
1Universitätsmedizin der Johannes Gutenberg-Universität Mainz Zentrum für Kardiologie Mainz, Deutschland; 2Universitätsmedizin der Johannes Gutenberg-Universität Mainz Klinik und Poliklinik für Diagnostische und Interventionelle Radiologie Mainz, Deutschland; 3Universitätsmedizin der Johannes Gutenberg-Universität Mainz Kardiologie 1, Zentrum für Kardiologie Mainz, Deutschland
Purpose
In the past, studies have already demonstrated that using ultra-high spatial resolution photon counting detector coronary CT angiography, can reduce bias compared to invasive coronary angiography. To confirm this evidence however, a comparison to a reference standard such as intravascular lumen area quantification by intravascular imaging is still missing. Intracoronary optical coherence tomography (OCT) allows for very precise intravascular lumen area determination .Therefore in this study we compared PCD-CCTA with intracoronary OCT.
Materials and Methods
In this study we identified patients with stable chest pain who underwent both PCD-CCTA (acquisition at collimation of 120x0.2mm, reconstructions in both 0.6mm and 0.2mm slice thickness, Bv64 reconstruction kernel, quantum iterative reconstruction level 4) and invasive angiography with steady-pullback OCT and retrospectively included those in this study. First distances to landmarks were defined in order to cross-match localizations between CCTA and OCT. Vessels then were analysed by measuring lumen area every 10 mm. Analysis was performed independently by a specifically trained cardiologist and radiologist who were blinded to each other’s results. Results were subsequently compared on a per-lumen area basis using Pearson’s correlations, paired t-tests and Bland-Altmann analyses.
Results
We were able to include 7 patients in this study and analysed 31 lumen areas with both techniques showing a strong correlation between OCT and PCD-CCTA for both reconstructed slice thicknesses (Pearson’s r =0.82 for 0.6mm and r=0.92 for 0.2mm). There was minimal bias towards smaller measurements from PCD-CCTA for both reconstructed slice thicknesses (mean bias -0.20 mm2 and -0.45 mm2 for 0.6 and 0.2 mm reconstructions, respectively). Limits of agreement were narrower for smaller slice thicknesses (-3.3 to 2.9 for 0.6mm vs. -2.8 to 1.7 for 0.2mm).
Conclusion
Using Intracoronary optical coherence tomography we could confirm minimal bias for measurements from photon-counting detector CT coronary angiographies in patients with stable chest pain. Higher spatial resolution of 0.2mm slice thickness reconstructions can narrow limits of agreement.
Clinical Relevance Statement
A reduction of bias between non-invasive PCD-CCTA and intravascular imaging to clinically acceptable levels can lead to less unnecessary down-stream testing in chest pain patients.