Polymer-free drug-eluting stents for coronary artery disease.

Polymer-free drug-eluting stents (PF-DES) were designed with the expectation of avoiding late restenosis and thrombosis related to the polymer used in traditional DES platforms. Furthermore, due to similarities with bare metal stents after drug elution, PF-DES has been considered as particularly suitable for patients at high bleeding risk. A variety of PF-DES platforms have been clinically tested. Despite their theoretical advantages, PF platforms showed comparable clinical outcomes with modern permanent- or biodegradable polymer-based DES up to 5 years after implantation. Use of more biocompatible polymers on the modern DES platforms is one of the reasons therefore. Their improved safety profile allows already less intensive antithrombotic regimes after DES. Hence, nowadays PF-DES platforms can be considered as one of many DES options for percutaneous treatment of coronary artery disease.

Clinical restenosis and its predictors after implantation of everolimus-eluting bioresorbable vascular scaffolds: results from GABI-R.

AIMS: The aim of this study was to assess clinical restenosis and its predictors after implantation of bioresorbable vascular scaffolds (BVS) in everyday practice in the large-scale German-Austrian ABSORB Registry (GABI-R). METHODS AND RESULTS: Between November 2013 and January 2016, 3,264 patients underwent BVS implantation in the 93 centres of GABI-R. At six-month follow-up, 24 patients experienced clinically indicated target lesion revascularisation (cTLR) unrelated to BVS thrombosis (cumulative incidence 0.76%; angiographically, 58.3% of in-BVS restenosis of focal pattern). Compared to patients without cTLR, patients with cTLR had more lesions per patient (1.83±1.0 vs. 1.36±0.7), complex (52.3% vs. 36.2%) and mild-to-moderately calcified lesions (65.9% vs. 60.5%) treated, and more frequently had overlapping BVS (22.2% vs. 10.8%), all p<0.05. Implanted BVS length was 40.0 mm (28.0, 46.9) vs. 23.0 mm (18.0, 30.0), p<0.001, remaining in the multivariable analysis the only independent predictor of cTLR (hazard ratio 1.02, 95% CI: 1.01-1.04, p<0.001). The myocardial infarction rate was also significantly higher among patients with cTLR, 29.2% vs. 1.7%, p<0.0001. CONCLUSIONS: cTLR related to BVS restenosis at six months after BVS implantation is a rare event depending on implanted BVS length. Whether cTLR increases the myocardial infarction risk needs to be evaluated at longer-term follow-up and within the setting of adequately powered randomised trials.