Multislice computed tomography assessment of everolimus-eluting Absorb bioresorbable scaffolds in comparison with metallic drug-eluting stents from the ABSORB Japan randomised trial

Aims: Blooming artefacts limit accurate coronary assessment by multislice computed tomography (MSCT) in metallic stents. We sought to investigate whether bioresorbable vascular scaffolds (BVS) could be better assessed by MSCT. Methods and results: Among 400 patients in the randomised ABSORB Japan trial, a pre-specified MSCT substudy was performed in 98 patients (103 lesions) in the BVS arm and 49 patients (49 lesions) in the cobalt-chromium everolimus-eluting stent (CoCr-EES) arm at 13 months prior to follow-up angiography. The assessability of BVS by MSCT was superior to that of CoCr-EES (94% versus 67%, p<0.001). Blooming artefacts were the main reason CoCr-EES could not be analysed (29%), while marker artefacts precluded analysis in 1.1% of BVS. In the CoCr-EES arm, non-assessable lesions were more prevalent in segments with 2.5 mm stents compared to 3.0 or 3.5 mm stents (75.0% versus 23.5%, p=0.01), while in the BVS arm image quality was good regardless of the diameter. The in-device minimal lumen diameter by MSCT was smaller than that by QCA with a difference of 0.61 mm in the CoCr-EES arm, vs. only 0.026 mm in the BVS arm. Conclusions: The feasibility of MSCT assessment of BVS-treated lesions was greater than that for lesions with CoCr-EES.