Long‐term outcomes of patients undergoing coronary sinus reducer implantation ‐ A multicenter study

BACKGROUND: Coronary sinus (CS) narrowing by reducer implantation has emerged as a safe and effective therapy for patients suffering from refractory angina. However, data regarding the clinical benefit of this treatment over time is lacking. METHODS: Patients undergoing successful reducer implantation were enrolled prospectively to clinical registries at three medical centers. Those with more than 2-years of follow-up were included in the present analysis. Peri-procedural data, data regarding adverse events, and current evaluation of angina severity (Canadian Cardiovascular Society [CCS] class) were collected. RESULTS: Overall, 99 consecutive patients (77% males, mean age 69.8 ± 9.4) with severe angina were enrolled between September 2010 and October 2017 and included in the present analysis. No procedure-related complications were recorded. During a median follow up time of 3.38 years (IQR 2.95-4.40), 15.1% of the patients died, 9% experienced myocardial infarction (MI) and 21% underwent percutaneous coronary intervention (PCI). Mean CCS class was 3.1 ± 0.5 at baseline, improved to 1.66 ± 0.8 at 1 year (p < .001), and remained low through 2-years and at last follow up (1.72 ± 0.8 and 1.71 ± 0.8, p > 0.5 for both, in comparison to 1 year). At baseline 91% of patients reported severe disabling angina (CCS class 3-4), at 1 year only 17.9% suffered from disabling angina, p < .001, and this portion remained low overtime (19% at last follow up). CONCLUSION: Long-term mortality of patients undergoing reducer implantation is similar to that reported for patients with stable coronary artery disease. The previously reported short-term efficacy of the reducer, reflected by significant improvement of angina symptoms, is maintained over time.