Study population
This study is a sub‐analysis of the Gangwon percutaneous coronary intervention (PCI) registry (ClinicalTrials.gov Identifier: NCT02038127). Gangwon PCI registry is an unrestricted, prospective, multicenter, and observational registry which enrolled all‐comer patients who underwent PCI from four hospitals. Among patients who underwent PCI between January 2019 and December 2021, as the ultra‐long 48 mm DES was available, we selected patients with at least one lesion length of >40 mm. Patients treated with one or more ultra‐long DESs, either 48 mm Xience Xpedition (everolimus‐eluting stent, Abbott Vascular) or 48 mm Synergy XD (everolimus‐eluting stent, Boston Scientific), comprised the ultra‐long DES group. The others were included in the conventional DES group. The local Institutional Review Board approved the study protocol (CR322080), and this study was conducted according to the principles of the Declaration of Helsinki, revised in 2013. Written informed consent was obtained from all patients.