Long-term effect of biodegradable vs. durable polymer everolimus-eluting stents on neoatherosclerosis in ST-segment elevation myocardial infarction: the CONNECT trial

Background and Aims Neoatherosclerosis is a leading cause of late (>1 year) stent failure following drug-eluting stent implantation. The role of biodegradable (BP) vs. durable polymer (DP) drug-eluting stents on long-term occurrence of neoatherosclerosis remains unclear. Superiority of biodegradable against durable polymer current generation thin-strut everolimus-eluting stent (EES) was tested by assessing the frequency of neoatherosclerosis 3 years after primary percutaneous coronary intervention (pPCI) among patients with ST-segment elevation myocardial infarction (STEMI). Methods The randomized controlled, multicentre (Japan and Switzerland) CONNECT trial (NCT03440801) randomly (1:1) assigned 239 STEMI patients to pPCI with BP-EES or DP-EES. The primary endpoint was the frequency of neoatherosclerosis assessed by optical coherence tomography (OCT) at 3 years. Neoatherosclerosis was defined as fibroatheroma or fibrocalcific plaque or macrophage accumulation within the neointima. Results Among 239 STEMI patients randomized, 236 received pPCI with stent implantation (119 BP-EES; 117 DP-EES). A total of 178 patients (75%; 88 in the BP-EES group and 90 in the DP-EES group) underwent OCT assessment at 3 years. Neoatherosclerosis did not differ between the BP-EES (11.4%) and DP-EES (13.3%; odds ratio 0.83, 95% confidence interval 0.33-2.04, P = .69). There were no differences in the frequency of fibroatheroma (BP-EES 9.1% vs. DP-EES 11.1%, P = .66) or macrophage accumulation (BP-EES 4.5% vs. DP-EES 3.3%, P = .68), and no fibrocalcific neoatherosclerosis was observed. Rates of target lesion failure did not differ between groups (BP-EES 5.9% vs. DP-EES 6.0%, P = .97). Conclusions The use of BP-EES for primary PCI in patients presenting with STEMI was not superior to DP-EES regarding frequency of neoatherosclerosis at 3 years.