Very Late Scaffold Thrombosis of Bioresorbable Vascular Scaffold: Systematic Review and a Meta-Analysis.

OBJECTIVES: This study sought to compare the 2-year outcomes between bioresorbable vascular scaffold (BVS) and everolimus-eluting metallic drug-eluting stent (EES).

BACKGROUND: The occurrence of very late stent/scaffold thrombosis (VLST) of BVS beyond 1 year after implantation is an increasing concern.

METHODS: We conducted a meta-analysis of 24 studies (BVS: n = 2,567 and EES: n = 19,806) reporting the 2-year outcomes of BVS and/or EES to compare the risk of BVS versus EES for stent/scaffold thrombosis (ST) and target lesion failure (TLF) in 7 comparative studies (3 randomized and 4 observational), and to estimate the pooled incidence rates of ST and TLF including additional 17 single-arm studies.

RESULTS: In the 7 comparative studies, the risk for VLST between 1 and 2 years was numerically higher in BVS than in EES (odds ratio [OR]: 2.03 [95% confidence interval (CI): 0.62 to 6.71]). The excess risk of BVS relative to EES for ST through 2 years was significant (OR: 2.08 [95% CI: 1.02 to 4.26]). The risk for TLF was neutral between BVS and EES. In the 24 studies, the pooled estimated incidence rates of VLST, and ST through 2 years were higher in BVS than in EES (0.240 [95% CI: 0.022 to 0.608]% vs. 0.003 [95% CI: 0.000 to 0.028]%, and 1.43 [95% CI: 0.67 to 2.41]% vs. 0.56 [95% CI: 0.43 to 0.70]%, respectively). The corresponding rates for TLF were comparable between BVS and EES (1.88 [95% CI: 1.30 to 2.55]% and 1.78 [95% CI: 1.17 to 2.49]% and 7.90 [95% CI: 6.26 to 9.69]% and 7.49 [95% CI: 5.86 to 9.29]%, respectively).

CONCLUSIONS: In this meta-analysis, BVS as compared with EES was associated with higher risk for VLST between 1 and 2 years and ST through 2 years.