Association between inflammatory biomarkers and neointimal response following elective implantation of the ABSORB bioresorbable vascular scaffold.

INTRODUCTION: The ABSORB bioresorbable vascular scaffold (BVS) is associated with greater neointimal proliferation and thrombotic rate than the metal stent. The role of inflammatory biomarkers on neointimal proliferation has not been studied in the setting of BVS implantation.

PATIENTS AND METHODS: Thirty patients had arterial blood sampling before elective percutaneous coronary intervention with the ABSORB BVS and at 9-months follow-up. Plasma levels of interleukin-6, soluble CD40 ligand, monocyte chemotactic protein-1 and C-reactive protein were measured using enzyme-linked immunosorbent assay. Baseline and follow-up levels were compared for each biomarker. Optical frequency domain imaging was performed at follow-up and the neointimal burden was calculated as the ratio of neointimal area to scaffold area. The levels of inflammatory mediators were correlated with the neointimal burden.

RESULTS: There was no significant increase in the levels of biomarkers from baseline to follow-up. Median C-reactive protein levels changed from 1.1 [interquartile range (IQR): 0.5-2.5] to 2.2 (IQR: 0.5-3.5) μg/ml, interleukin-6 from 1.0 (IQR: 0.6-1.4) to 1.0 (95% confidence interval: 0.6-1.4) pg/ml, monocyte chemotactic protein-1 from 120.4 (IQR: 86.0-153.4) to 102.0 (IQR: 70.3-148.1) pg/ml and soluble CD40 ligand from 108.3 (IQR: 74.1-173.7) to 112.0 (IQR: 71.0-225.9) pg/ml. The average neointimal burden in the cohort was 18±6%. Baseline, follow-up and change in plasma levels of inflammatory markers between these two time points did not correlate with the neointimal burden.

CONCLUSION: Elective percutaneous coronary intervention with the ABSORB BVS does not provoke a chronic inflammatory response. The degree of neointimal proliferation after elective implantation of the ABSORB BVS is independent of the pre-existing inflammatory environment.