Difference of vascular healing between bioabsorbable-polymer and durable-polymer new generation drug-eluting stents: an optical coherence tomographic analysis.

The comparison of bioabsorbable-polymer and durable-polymer stents has continued to be debated, and there is ongoing concern regarding vascular healing and late stent thrombosis. This study compared the vascular healing at 8-month follow-up by optical coherence tomography (OCT) between 4 different kinds of new generation drug-eluting stents (DESs). We enrolled 112 patients (112 de novo lesions) who underwent OCT guided percutaneous coronary intervention with 4 kinds of new generation DESs including bioabsorbable-polymer everolimus-eluting stents (BP-EESs), bioabsorbable-polymer sirolimus-eluting stents (BP-SESs), durable-polymer everolimus-eluting stents (DP-EESs), and durable-polymer zotarolimus-eluting stents (DP-ZESs) and an 8-month follow-up angiogram and OCT were performed between July 2016 and April 2018. We divided them into two groups, namely BP and DP groups. We compared the OCT parameters including the percentage of uncovered struts, malapposed struts and the mean neointimal hyperplasia (NIH) thickness between the two groups. BP group consisted of 51 lesions (BP-EESs were used in 27, BP-SESs in 24 lesions) and DP group consisted of 61 lesions (DP-EESs were used in 35 and DP-ZESs in 26 lesions). The percentage of uncovered struts and malapposed struts were significantly lower (7.2 ± 8.9 vs. 15.0 ± 17.1%, p = 0.01, 0.9 ± 1.7 vs. 2.7 ± 5.2%, p = 0.03) and the mean NIH thickness was significantly thicker in BP group than DP group (112 ± 54 vs. 83 ± 31 µm, p < 0.01). The present OCT study demonstrated that uncovered struts and malapposed struts were less common with bioabsorbable-polymer stents than with durable-polymer stents.