P1823 Feasibility of CCTA in assessment of luminal changes and coronary shear stress evolution after implantation of bioresorbable vascular scaffolds

Abstract

Abstract Funding Acknowledgements PlaqueImage - financed by the National Authority of Scientific Research and Innovation and the Romanian Ministry of European Funding Background Coronary shear stress (CSS) is a well-established local mechanical factor in atherogenesis, progression and destabilization of atherosclerotic plaques. Analysis of CSS after coronary stent placement is still lacking of large clinical studies. Purpose: The aim of this study was to: (1) test the feasibility of Coronary Computed Tomography Angiography (CCTA) for assessment of local hemodynamic and luminal changes after implantation of bioresorbable vascular scaffolds (BVS), and (2) to investigate CSS modifications after BVS implantation. Methods: We conducted a single center, prospective pilot study on 73 patients with coronary artery disease who underwent elective percutaneous coronary intervention (PCI); group 1 (n = 30) – patients with BVS and group 2 (n = 43) – patients with bare metal stent (BMS) implanted. CCTA scanning was performed in all patients prior PCI and at 12 months after PCI. The mean CSS at proximal and at distal part of the stented segment and at the level of the minimal lumen area (MLA) was calculated at baseline and at 12 months after BVS placement. Results: CCTA revealed a higher incidence of severe coronary stenosis in group 1 (73%) than in group 2 (30%) (p < 0.0001). Sensibility of visual evaluation for identification of in-stent restenosis on CCTA was increased in BVS group (94%) than in BMS group (76.19%) (p = 0.0006), hence the group 1 had lower incidence of non-diagnostic evaluations. Mean CSS at the stented site was significantly lower at 12 months (1.9 +/- 0.68 Pa) that average CSS at baseline (2.87 +/- 3.08 Pa) (p = 0.0001). CSS analysis showed also a significantly decreased values at proximal level from 3.39 +/- 1.93 Pa at baseline to 1.91 +/- 0.68 Pa at follow up (p < 0.0001), but not a significant decrease at distal part – 1.3+/-0.72 Pa at baseline and 1.59 +/- 0.65 Pa at 12 months follow up (p = 0.9). Conclusions: CCTA is a feasible technique for assessment of luminal changes following BVS implantation. BVS implantation contribute to the improvement of local hemodynamics by restoring physiological pattern of coronary flow, as demonstrated by the computational fluid hemodynamics assessment of coronary circulation.