Background: Bioresorbable scaffolds (BRS) have been introduced to overcome the limitations of drug-eluting stents and the ABSORB (Everolimus-Eluting BRS, Abbott Vascular, Santa Clara, CA, USA) was the most extensively tested. Nevertheless, major RCTs reported higher rates of target lesion failures and BRS thrombosis at 3 years follow-up, bringing to the withdrawing of the device from the market. It has been suggested that a better lesions selection and an optimized implantation technique could mitigate the displayed adverse results.
Methods: Consecutive patients undergoing BRS implantation were included in this observational, single center study. Clinical follow-up was conducted up to 4 years. Endpoint of interest was the target lesion failure (TLF), a composite outcome including cardiac death, target vessel myocardial infarction and target lesion revascularization.
Results: A total of 62 patients with a mean age of 55±8.5 years were analyzed of which 70.9% presented with an acute coronary syndrome and 59.6% with myocardial infarction. A total of 100 lesions were treated and 51.6% were complex (B2/C). Predilatation was performed in all the case, post-dilatation in 74.1%. All the target vessel reference diameter (RVD) were >2.5 mm (average RVD 3.2±0.24 mm). At 4 years, the rate for TLF was 6.9%. Subgroup's analysis did not show significative differences among groups although consistently higher event rates were found for RVD <2.5 mm (12.6% vs. 6.4%, P=0.5), BRS overlapping (11.8% vs. 5%, P=0.2) and ticagrelor instead of clopidogrel on top of cardioaspirin (9.1% vs. 3%, P=0.2).
Conclusions: This small-sized real-world registry displays lower rates of clinical events during long-term follow-up in respect to previous studies. The avoidance of implantation in small vessels, inclusion of acute myocardial infarction and extensive performance of BRS post-dilatation could explain the observed better results. Long-term outcomes of the ongoing ABSORB IV Trial are needed to confirm this data.