Abstract Introduction The coronary sinus Reducer emerged as a complementary therapy in patients with angina refractory to optimal medical therapy and not amenable to revascularization. Aim The aim of this study was to assess the safety and efficacy of the Reducer in a real-world cohort of patients presenting with refractory angina. Methods and population Twenty-six patients with refractory angina, objective evidence of myocardial ischemia attributable to the left coronary artery and deemed unsuitable for revascularization were treated with Reducer at a single center between April 2018 and January 2023. Safety endpoints were procedural success and complications. Efficacy endpoints, assessed at 6-month, were a reduction in Canadian Cardiovascular Society angina (CCS) class and a reduction in pharmacological antianginal therapy. Results Twenty-one (81%) patients had end-stage coronary artery disease without targets for further revascularization (13 had previous CABG ± PCI and 8 had only PCI) and 5 patients had microvascular disease without epicardial stenosis. All procedures were performed via right jugular vein. The mean procedure and fluoroscopy duration were 66±29 and 19±8 minutes. Procedural success was achieved in all patients, with no device related complications. There was one cardiac tamponade, promptly treated with pericardiocentesis. Regarding the efficacy endpoint, 21 patients (81%) had at least 1 grade reduction in CCS class, 13 patients (50%) had at least 2 class reductions, and 7 patients (28 %) became asymptomatic, with a mean reduction of CCS class of 1.4±0.9, from 2.6±0.5 to 1.2±0.9 (p=0.001) at 6-month follow-up. During this time frame, twelve patients (46%) withdrew or reduced the dose of at least one anti-anginal drug. The mean reduction of anti-anginal drugs was 0.54 ±0.86, from 3.5±1.02 to 2.9±1.07 (p=0.04). Conclusion In this real-world, single-center experience, implantation of Reducer was safe and associated with improvement of angina and reduction of anti-anginal drugs intake in patients with refractory angina unsuitable for revascularization.