Vascular response to everolimus- and biolimus-eluting coronary stents versus everolimus-eluting bioresorbable scaffolds - an optical coherence tomography substudy of the EVERBIO II trial

QUESTIONS UNDER STUDY: Head-to-head optical coherence tomography (OCT) data comparing metallic stents with bioresorbable vascular scaffolds (BVS) are lacking. This study assessed vascular healing at 9-month follow-up after implantation of everolimus-and biolimus-eluting stents (EES; BES) and everolimus-eluting BVS. METHODS: OCT was performed in 74 patients enrolled in the EVERBIO II (NCT01711931) trial (23 with EES: 26 lesions, 7 625 struts; 23 with BES: 26 lesions, 6 140 struts; 28 with BVS: 33 lesions, 10 891 struts). OCT images were acquired using the pullback and nonocclusive flushing technique and analysed offline. RESULTS: BVS demonstrated fewer uncovered struts per patient (12 +/- 27 [3.8 +/- 8.4%] vs 59 +/- 55 [21.8 +/- 13.7%] in the EES&BES group, p <0.001), and thicker neointimal hyperplasia (BVS 102 +/- 44 mu m vs EES&BES 66 +/- 36 mu m, p <0.01). There was no significant difference with regard to malapposed struts (2.1 +/- 2.7% in the BVS vs 4.4 +/- 8.8% in the EES&BES group, p = 0.41). In a predefined signal intensity scale, quantitative analysis of the "key component" (black) revealed lower intensity in BVS than EES& BES (14 +/- 23% vs 13 +/- 12%, p = 0.007). Intensity was lower in polylactide-containing stents (BVS&BES) than in EES (15 +/- 19% vs 10 +/- 10%, p <0.001). CONCLUSIONS: BVS has fewer uncovered struts and presents with a thicker neointimal coverage compared with EES& BES. It is not known whether this improved capping correlates with superior vascular healing. Polylactide-containing stents (BVS and BES) demonstrate lower peristrut intensity compared with EES.