ABSORB biodegradable stents versus second-generation metal stents: a comparison study of 100 complex lesions treated under OCT guidance

Abstract

Objectives: The aim of this study was to compare the acute performance of the PLLA ABSORB bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, California) with second-generation metal drug-eluting stents (DES) in complex coronary artery lesions.

Background: Thick polymer-based BVS have different mechanical properties than thin second-generation DES. Data on the acute performance of BVS are limited to simple coronary lesions treated in trials with strict inclusion criteria.

Methods: Fifty complex coronary lesions (all type American College of Cardiology/American Heart Association B2-C) treated with a BVS undergoing a final optical coherence tomography (OCT) examination were compared with an equal number of matched lesions treated with second-generation DES. The following stent performance indexes were assessed with OCT: mean and minimal area, residual area stenosis (RAS), incomplete strut apposition (ISA), tissue prolapse, eccentricity index, symmetry index, strut fracture, and edge dissection.

Results: One hundred lesions from 73 patients were analyzed. A higher balloon diameter/reference vessel diameter ratio was used for predilation in the BVS group (p < 0.01). Most of the BVS and DES were post-dilated with short noncompliant (NC) balloons of similar diameter. OCT showed in the BVS group a higher tissue prolapse area (p = 0.08) and greater incidence of ISA at the proximal edge (p = 0.04) with no difference in the overall ISA. The RAS was 20.2% in the BVS group and 21.7% in the DES group (p = 0.32). There was no difference in the eccentricity index. The minimal and mean lumen areas were similar in the 2 groups. Two cases of strut fractures occurred after the BVS, whereas none was observed in the DES.

Conclusions: Based on OCT, the BVS showed similar post-procedure area stenosis, minimal lumen area, and eccentricity index as second-generation DES. The different approach for lesion preparation and routine use of OCT guidance during BVS expansion may have contributed to these results.

Keywords: bioresorbable vascular scaffold; drug-eluting stent; optical coherence tomography; stent.