Serial Comparison of Neointimal Coverage between Two Different Concept Stents: Optical Coherence Tomographic Evaluation

Abstract

Recently, two different concept drug-eluting stents including biolimus A9-eluting stents (BES) with biodegradablepolymer and everolimus-eluting stents (EES) with durable biocompatible-polymer are available. However, serial comparison of BES and EES on neointimal coverage is not fully investigated. We performed serial evaluation of neointimal coverage at 8 months (BES polymer remained) and 20 months follow-up (BES polymer absorbed) by optical coherence tomography (OCT) for 14 BESs and 10 EESs, and compared uncovered strut proportion (%Uncovered), malapposed strut proportion (%Malapposed) and average neointimal hyperplasia thickness (Ave- NHT), numbers of extra stent lumen (ESL) and multiple interstrut hollow (MIH) calculated by OCT between two DESs, at 8 months and 20 months follow-up, respectively. As a result. at 8 months, Ave-NHT of EES was significantly higher than BES (124 ± 65 E¥m vs 83 ± 47 E¥m, p<0.001) but %Uncovered and %Malapposed were similar between the two groups. At 20 months, %Uncovered and ESL of EES were significantly lower than BES (0.8 ± 5.7% vs 4.8 ± 12.7%, p<0.001 and 0.86 ± 1.28 vs 0.09 ± 0.16, p=0.043) and Ave-NHT of EES was significantly higher than BES (185 ± 88 E¥m vs 90 ± 46 E¥m, P<0.001). In conclusion, EES showed favorable neointimal healing compared to BES