Aims: The behaviour of side branches (SBs) covered by a bioresorbable vascular scaffold (BVS) is not well known. This study analysed the rate of side branch occlusion (SBO) immediately after BVS implantation, its clinical impact, predictors of SBO and the fate of such SBs at follow-up.
Methods and results: We assessed 140 patients with 346 jeopardised SBs divided into three groups: small (<1 mm, n=181), intermediate (1-2 mm, n=102) and large (>2 mm, n=63). SBO was defined as a TIMI flow 0 or 1. Computed tomography was scheduled at six months for patients with jailed SBs >1 mm. Immediate occlusion occurred in 31 (9%) SBs: 22 (12%) small, 8 (8%) intermediate and one (1.6%) large, while post-procedural SBO was 5.5%. In-hospital events included one thrombosis (0.7%) and eight non-Q-wave myocardial infarctions (6%). After 17±3 months, one patient died (0.7%) and six patients needed repeat revascularisation (4%). Re-evaluation showed no late SBO at 7±3 months. Predictors of SBO were: small SBs (OR 2.06, 95% CI: 1.08-4.63; p<0.05) and stenosis >50% at the origin (OR 17.22, 95% CI: 7.79-38.10; p<0.01).
Conclusions: The incidence of SBO and its clinical impact were low when SBs >1 mm were covered. These favourable results were maintained at midterm.