Overview of the virtual 2020 FDA's circulatory system devices advisory panel on Neovasc reducer system

Coronary Sinus Reducer Therapy for Refractory Angina and its Role in Modern Interventional Practice: A Contemporary Review

Coronary sinus reducer (CSR) implantation is an emerging treatment option for patients with refractory angina. This condition represents a major global cardiovascular healthcare challenge, with patients experiencing chronic anginal symptoms that significantly impair their quality of life and for whom few effective treatments exist. The clinical burden of refractory angina is only set to grow because of improved survival from coronary artery disease, increased life expectancy and the presence of residual angina after percutaneous or surgical coronary revascularisation. Therefore, new, effective, evidence-based therapies are urgently needed. In this review, we highlight the unmet clinical needs of patients with refractory angina, discuss the development of the CSR device and review the preclinical and clinical evidence base underlying CSR implantation. In addition, we discuss the current role of CSR implantation in contemporary interventional practice, highlighting knowledge gaps and discussing areas of on-going research.

The Effectiveness of CS Reducer for the treatment of Refractory Angina - a Meta-Analysis

BACKGROUND

Refractory angina is a debilitating condition that affects quality of life of patients worldwide, that after exhausting standard available therapies are regarded as "no option" patients. Recently, coronary sinus (CS) Reducer implantation became available and is gaining popularity in the treatment of refractory angina. The effectiveness of this therapy was demonstrated in one randomized sham-control trial and numerous uncontrolled prospective studies entailing altogether several hundred patients. We performed a meta-analysis to incorporate the data and elucidate its efficacy and safety.

METHODS

A meta-analysis of prospective studies assessing the effects of CS narrowing published in English until June 2021 was performed. The primary outcome was the proportion of patients improving ≥1 class in the Canadian Cardiovascular Society (CSS) angina score. Other endpoints included proportion of patients improving ≥2 CCS classes, procedural success, periprocedural complications, changes in Seattle Angina Questionnaire (SAQ) scores, and six-minute walk test (6MWT).

RESULTS

Data from 9 studies, including 846 patients was included. An improvement of ≥1 CSS class occurred in 76% [95% CI 73%- 80%] of patients. Improvement of ≥2 CSS classes was observed in 40% of patients (95% CI of 35-46%). Procedure success was 98%, with no major and 3% of non-major periprocedural complications. Post procedural SAQ scores and 6MWT distance were significantly improved.

CONCLUSIONS

In patients suffering from angina refractory to medical and interventional therapies, CS narrowing implantation improves symptoms and quality of life, with a low complication rate. These results are consistent in one randomized trial and in multiple prospective, uncontrolled studies.