Clinical Outcomes of Successful Revascularization of Chronic Total Coronary Occlusions with Bioresorbable Vascular Scaffolds: A Systematic Review

Revascularization of chronic total occlusions (CTO) with percutaneous coronary intervention is associated with favorable long-term clinical and echocardiographic outcomes. Whether bioresorbable vascular scaffolds (BVS) would be advantageous in the treatment of CTO is unknown as patients with these lesions were generally excluded from large BVS randomized trials. We performed a systematic review, which sought to summarize known data on mid- to long-term clinical outcomes for BVS in CTO. We searched MEDLINE, EMBASE, clinicaltrials.gov, and the Cochrane Library through April 2018 to look for studies on implantation of BVS in CTO. Outcomes of interest included myocardial infarction, cardiac death, all-cause mortality, major adverse cardiac events (MACE), vessel restenosis, scaffold thrombosis, and target lesion revascularization. A total of 13 articles met the inclusion criteria for analysis. All studies were observational with a total number of patients of 1,077. Only two studies included comparator groups which retrospectively compared BVS with drug-eluting stents (DES). The studies had variable size (21 to 537) and follow-up duration (3-23 months). The review showed favorable outcomes for BVS implantation in CTO with the reported incidence of MACE ranged from 0% to 6.7% with no significant differences between BVS and DES groups in double arm studies. Although data on the use of first-generation BVS in CTO are sporadic and limited by small sample observational studies, available evidence is promising and suggests of acceptable outcomes comparable with second generation DES. Further investigation with randomized clinical trials and use of newer generation scaffolds is required.