Accuracy of coronary computed tomography angiography for bioresorbable scaffold luminal investigation: a comparison with optical coherence tomography

Carlos Collet, Yohei Sotomi, Rafael Cavalcante, Taku Asano, Yosuke Miyazaki, Erhan Tenekecioglu, Pieter Kistlaar, Yaping Zeng, Pannipa Suwanasson, Robbert J. de Winter, Koen Nieman, Patrick W. Serruys, Yoshinobu Onuma

To establish the accuracy of coronary computed tomography angiography (CTA) for in-scaffold quantitative evaluation with optical coherence tomography (OCT) as a reference. The translucent backbone of the bioresorbable scaffold allow us to evaluate non-invasively the coronary lumen with coronary CTA. In the ABSORB first-in-man studies, coronary CTA was shown to be feasible for quantitative luminal assessment. Nevertheless, a comparison with an intravascular modality with higher resolution has never been performed. In the ABSORB Cohort B trial, 101 patient with non-complex lesions were treated with the fully biodegradable vascular scaffold. For this analysis, all patients who underwent coronary CTA at 18 months and OCT within ±180 days were included. Coronary CTA and OCT data were analysed at an independent core laboratory for quantitative cross-sectional luminal dimensions. The primary objective was the accuracy and precision of coronary CTA for in-scaffold minimal lumen area assessment, with OCT as a reference. Among the 101 patients of the ABSORB Cohort B trial, 35 underwent both OCT and coronary CTA. The feasibility of quantitative evaluation was 74%. In the scaffolded segment, coronary CTA underestimated minimal lumen area by 9.8% (accuracy 0.39 mm(2), precision 1.0 mm(2), 95% limits of agreement -1.71 to 2.50 mm(2)). A similar level of agreement was observed in the non-scaffolded segment. Compared to OCT, coronary CTA appears to be accurate for the estimation of in-scaffold luminal areas, with no difference compared to the non-scaffolded region.