Jun Jie ZhangXiao Fei GaoYa Ling HanJing KanLing TaoZhen GeDamras TresukosolShu LuLi Kun MaFeng LiSong YangJun ZhangMuhammad MunawarLi LiRui Yan ZhangHe Song ZengTeguh SantosoPing XieZe Ning JinLeng HanWei Hsian YinXue Song QianQi Hua LiLang HongChotnoparatpat PaiboonYan WangLi Jun LiuLei ZhouXue Ming WuShang Yu WenQing Hua LuJun Qiang YuanLiang Long ChenFrancesco LavarraAlfredo E. RodríguezLi Min ZhouShi Qin DingKitigon VichairuangthumYuan Sheng ZhuMeng Yue YuChan ChenImad SheibanYong XiaYu Long TianZheng Lu ShangQing JiangYong Hong ZhenXin WangFei YeNai Liang TianSong LinZhi Zhong LiuShao Liang ChenCheng Hsin General HospitalGansu Province People's HospitalShenyang General Hospital of PLAXinhua HospitalAnhui Provincial HospitalGuangzhou Red Cross HospitalBeijing Anzhen HospitalXijing HospitalUniversitas IndonesiaShandong UniversityFuwai HospitalHuazhong University of Science and TechnologyRuijin HospitalBangkok Hospital Medical CenterXuZhou Medical UniversityGuangdong Medical UniversityNanjing Medical UniversityUniversità degli Studi di TorinoFaculty of Medicine, Siriraj Hospital, Mahidol UniversitySanatorio Otamendi y MiroliBangplee HospitalHuainan Eastern HospitalWuxi Huishan District People's HospitalAnqing First People's HospitalChuzhou First People's HospitalCangzhou Central HospitalYixin People's HospitalZhangjiagang First People's HospitalJilin Heart HospitalXuyi People's HospitalHuai'an Second People's HospitalBinawaluya Cardiac CenterXia'Men Zhongshan HospitalFujian Union HospitalWuxi Third People's HospitalGeneral Hospital of Daqing Oil FieldTaicang People's HospitalNanjing Heart CenterHuainan First People's HospitalJintan People's HospitalLianyungang Hospital of Traditional Chinese MedicineLiyang Hospital of Traditional Chinese MedicineJiangxi Provincial People's HospitalChangshu First People's HospitalChangzhou Hospital of Traditional Chinese MedicineXinyang Central Hospital2019-08-282019-08-282018-03-01BMJ Open. Vol.8, No.3 (2018)204460552-s2.0-85044235775https://repository.li.mahidol.ac.th/handle/20.500.14594/46934© 2018 Article author(s) (or their employer(s) unless otherwise stated in the text of the article). All rights reserved. Introduction Provisional stenting (PS) for simple coronary bifurcation lesions is the mainstay of treatment. A systematic two-stent approach is widely used for complex bifurcation lesions (CBLs). However, a randomised comparison of PS and two-stent techniques for CBLs has never been studied. Accordingly, the present study is designed to elucidate the benefits of two-stent treatment over PS in patients with CBLs. Methods and analysis This DEFINITION II study is a prospective, multinational, randomised, endpoint-driven trial to compare the benefits of the two-stent technique with PS for CBLs. A total of 660 patients with CBLs will be randomised in a 1:1 fashion to receive either PS or the two-stent technique. The primary endpoint is the rate of 12-month target lesion failure defined as the composite of cardiac death, target vessel myocardial infarction (MI) and clinically driven target lesion revascularisation. The major secondary endpoints include all causes of death, MI, target vessel revascularisation, in-stent restenosis, stroke and each individual component of the primary endpoints. The safety endpoint is the occurrence of definite or probable stent thrombosis. Ethics and dissemination The study protocol and informed consent have been approved by the Institutional Review Board of Nanjing First Hospital, and accepted by each participating centre. Written informed consent was obtained from all enrolled patients. Findings of the study will be published in a peer-reviewed journal and disseminated at conferences.Mahidol UniversityMedicineArticleSCOPUS10.1136/bmjopen-2017-020019