Coronary Sinus Reducer Implantation for the Treatment of Chronic Refractory Angina: A Single-Center Experience

Abstract

Objectives: 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.

Background: The coronary sinus Reducer is a novel device to aid in the management of patients with severe angina symptoms refractory to optimal medical therapy and not amenable to further revascularization.

Methods: Fifty patients with refractory angina and objective evidence of myocardial ischemia who were judged unsuitable for revascularization were treated with coronary sinus Reducer implantation at a single center between March 2015 and August 2016. Safety endpoints were procedural success and the absence of device-related adverse events. Efficacy endpoints, assessed at 4- and 12-month follow-up, were a reduction in Canadian Cardiovascular Society angina class, improvement in quality of life assessed using the Seattle Angina Questionnaire, improvement in exercise tolerance assessed using the 6-min walk test, and reduction in pharmacological antianginal therapy.

Results: Procedural success was achieved in all patients, with no device-related adverse effects during the procedure or at follow-up. Regarding the efficacy endpoint, 40 patients (80%) had at least 1 reduction in Canadian Cardiovascular Society class, and 20 patients (40%) had at least 2 class reductions, with a mean class reduction to 1.67 ± 0.83 vs. 2.98 ± 0.52 (p < 0.001) at 4-month follow-up. All Seattle Angina Questionnaire items improved significantly (p < 0.001 for all). A significant increment in 6-min walk distance to 388.6 ± 119.7 m vs. 287.0 ± 138.9 m (p = 0.004) was observed. Sixteen patients (32%) and 3 patients (6%) demonstrated reductions of at least 1 or 2 antianginal drugs, respectively. The benefit of Reducer implantation observed at 4-month follow-up was maintained at 1 year.

Conclusions: In this real-world, single-center experience, implantation of the coronary sinus Reducer appeared safe and was associated with reduction in anginal symptoms and improvement in quality of life in patients with refractory angina who were not candidates for further revascularization.

Keywords: chronic refractory angina; coronary sinus reducer; optimal medical therapy.