The effectiveness and safety of the RESTORE® drug-eluting balloon versus a drug-eluting stent for small coronary vessel disease: study protocol for a multi-center, randomized, controlled trial.

OBJECTIVE: Small coronary vessel disease (disease affecting coronary vessels with main branch diameters of ≤ 2.75 mm) is a common and intractable problem in percutaneous coronary intervention (PCI). This study was designed to test the theory that the effectiveness and safety of drug-eluting balloons for the treatment of de novo lesions in small coronary vessels are non-inferior to those of drug-eluting stents. METHODS: We designed a prospective, multicenter, randomized, controlled clinical trial aiming to assess the effectiveness and safety of the RESTORE® (Cardionovum, Bonn, Germany) drug-eluting balloon (DEB) versus the RESOLUTE® (Medtronic, USA) drug-eluting stent (DES) in the treatment of small coronary vessel disease. This trial started in August 2016. A total of 230 patients with a reference vessel diameter (RVD) ≥ 2.25 mm and ≤ 2.75 mm were randomly assigned to treatment with a DEB or a DES at a 1:1 ratio. The study was also designed to enroll 30 patients with an RVD ≥ 2.00 mm and ≤ 2.25 mm in the tiny vessel cohort. RESULTS: The key baseline data include demographic characteristics, relative medical history, baseline angiographic values and baseline procedural characteristics. The primary endpoint is in-segment diameter stenosis at nine months after the index procedure. Secondary endpoints include acute success, all-cause death, myocardial infarction, target vessel revascularization, target lesion revascularization and stent thrombosis. CONCLUSIONS: The study will evaluate the clinical efficacy, angiographic outcomes, and safety of DEBs compared to DESs in the treatment of de novo coronary artery lesions in small vessels.