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

The Coronary Sinus Reducer Stent for the Treatment of Refractory Angina Pectoris: From the Conception of Innovation to Clinical Application

The Neovasc Coronary Sinus Reducer Stent (CSRS) was developed for the treatment of patients who continue to suffer from disabling symptoms despite optimal medical therapy. This patient population with refractory angina symptoms is expected to grow, since life expectancy of individuals with atherosclerotic coronary artery disease is increasing. In this paper, we discussed the development of a novel device the CSRS and the upside-down strategy to rebuild a retrograde coronary pressure that was attenuated by the atherosclerotic disease.

Safety and Effectiveness of Coronary Sinus Reducer in the Therapy of Refractory Angina Pectoris-Mid-Term Results of the Real-Life Cohort

Background: Despite continuous improvements in revascularization techniques, refractory angina without potential revascularization options remains a relevant clinical issue with significant impact on the patient's quality of life. Recently, a novel device, the Coronary Sinus Reducer (CSR), has been introduced into clinical practice as a therapeutic option for patients with disabling angina pectoris. In this single-center, observational study, we evaluated the mid-term (3-month) safety and efficacy of the CSR in a real-world cohort. Methods: The study population consisted of 55 patients with refractory angina without potential revascularization options, who were predominantly men (87.3%) with a high cardiovascular risk factor burden and advanced angina (baseline CCS angina class 3.15 ± 0.6). In terms of procedure safety, all patients underwent successful device deployment with only one periprocedural complication. Results: At the 3-month follow-up, we observed a statistically significant improvement in angina control measured CCS class and SAQ-7 total questionnaire along with increased abolition of physical limitation-6-MWT (233.3 ± 107.1 vs. 305.2 ± 126.8; p < 0.0001). Additionally, we observed significant improvement in terms of quality of life measurements SF-36, the EQ-5D-5L questionnaire, and the EQ-VAS. Conclusions: Our real-world data suggest that CSR implantation is a relatively safe procedure and appears to be particularly effective in relieving angina symptoms and improving quality of life in subjects with refractory angina.

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.

[Angina and no obstruction on coronary angiography : New approaches to the diagnosis and treatment of vasomotor disorders]

BACKGROUND

Clinical management of patients with angina and no obstructive coronary artery disease (ANOCA) is still challenging. This scenario affects up to 50% of patients undergoing diagnostic coronary angiography due to suspected coronary artery disease. Many patients report a long and debilitating history before adequate diagnostics and management are initiated.

OBJECTIVES

This article describes the current recommendations for diagnostic assessments and treatment in patients with ANOCA. Focus is placed on invasive diagnostics in the catheter laboratory, pharmacological/interventional treatment as well as the patient journey.

RESULTS

In patients with ANOCA, the current European Society of Cardiology (ESC) guidelines suggest that invasive assessments using acetylcholine and adenosine for the diagnosis of an underlying coronary vasomotor disorder should be considered. Acetylcholine is used to diagnose coronary spasm, whereas adenosine is used in conjunction with a wire-based assessment for the measurement of coronary flow reserve and microvascular resistance. The invasive assessments allow the determination of what are referred to as endotypes (coronary spasm, impaired coronary flow reserve, enhanced microvascular resistance or a combination thereof). Establishing a diagnosis is helpful to: (a) initiate targeted treatment to improve quality of life, (b) reassure the patient that a cardiac cause is found and (c) to assess individual prognosis.

CONCLUSIONS

Currently, patients with ANOCA are often not adequately managed. Referral to specialised centres is recommended to prevent long and debilitating patient histories until expertise in diagnosis and treatment becomes more widespread.

A budget impact model and a cost-utility analysis of reducer device (Neovasc) in patients with refractory angina

Background

Refractory angina (RA) is a chronic condition characterized by the presence of debilitating angina symptoms due to established reversible ischemia in the presence of obstructive coronary artery disease (CAD). Treatments for this condition have undergone major developments in recent decades; however, the treatment for RA remains a challenge for medicine. In this sense, the Coronary Sinus Reducer System (CSRS) stands as the last line of therapy for ineligible patients for revascularization with reversible ischemia. The purpose of this report is to evaluate the potential burden on the National Health Service (NHS) and measure the health effects in terms of both quantity (life years) and quality-of-life aspects related to the reducer.

Methods

Two different economic evaluation models were developed as part of the analysis. The budget impact was developed to estimate the potential burden on the NHS from incremental uptake of the use of the reducer in the target population. The utility cost analysis compares and evaluates the quality of life and health resource use and costs between the two alternatives, based on the research of Gallone et al. A deterministic and probabilistic sensitivity analysis was carried out to characterize the uncertainty around the parameters of the model.

Results

In the budget impact analysis (BIA), the reducer is shown to be more expensive in the first 2 years of the model, due to the gradual uptake in the market and the cost of the device. Starting from the third year, assuming maintenance of effectiveness, there are savings in terms of resource absorption in direct healthcare costs arising from hospitalizations, emergency department accesses, coronarography, and visits avoided.

Conclusion

The BIA and cost-effectiveness model show that the reducer device, despite an increase in resources absorbed in the first years of implementation and use, has the potential to result in increased quality of life in patients with RA. These costs are largely offset in the short term by the improved clinical outcomes achievable leading to savings from the third year onward in the BIA and a dominance ratio in the cost-utility analysis.

Coronary Sinus Narrowing Improves Coronary Microcirculation Function in Patients With Refractory Angina: A Multicenter Prospective INROAD Study

BACKGROUND

The underlying mechanisms responsible for the clinical benefits following coronary sinus narrowing and pressure elevation remain unclear. The present study aims to investigate whether coronary sinus narrowing improves the indexes of coronary microcirculatory function.

METHODS

Patients with refractory angina who had a clinical indication for reducer implantation underwent invasive physiological assessments before and 4 months after the procedure. The primary outcome was the change in the values of the index of microcirculatory resistance. Secondary end points included changes in coronary flow reserve and the resistive resistance ratio values. Angina status was assessed with the Canadian Cardiology Society class and the Seattle Angina Questionnaire.

RESULTS

Twenty-four patients with a history of obstructive coronary artery disease and prior coronary revascularization (surgical and percutaneous) treated with reducer implantation were enrolled, and 21 of them (87%) underwent repeated invasive coronary physiological assessment after 4 months. The index of microcirculatory resistance values decreased from 33.35±19.88 at baseline to 15.42±11.36 at 4-month follow-up (P<0.001; mean difference, -17.90 [95% CI, -26.16 to -9.64]). A significant (≥20% from baseline) reduction of the index of microcirculatory resistance was observed in 15 (71.4% [95% CI, 47.8%-88.7%]) patients. The number of patients with abnormal index of microcirculatory resistance (≥25) decreased from 12 (57%) to 4 (19%; P=0.016). Coronary flow reserve increased from 2.46±1.52 to 4.20±2.52 (mean difference, 1.73 [95% CI, 0.51-2.96]). Similar findings were observed for resistive resistance ratio values. Overall, 16 patients (76.1%) had an improvement of 1 Canadian Cardiology Society class. Seattle Angina Questionnaire summary score increase of around 3 points (3.01 [95% CI, 1.39-4.61]).

CONCLUSIONS

Coronary sinus reduction implantation is associated with a significant improvement in the parameters of coronary microcirculatory function. These findings provide insights into the improvement of angina symptoms and may have implications for the treatment of coronary microvascular dysfunction.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05174572.

Coronary sinus narrowing therapy: A "Reducer" for angina and beyond

Refractory Angina (RA) is an increasingly common clinical diagnosis, in which patients unsuitable for further percutaneous or surgical procedures experience anginal symptoms, despite receiving optimal medical therapy. This clinical condition challenges the everyday activities and diminishes the quality of life of these patients. A wide variety of novel therapies for this type of angina are being investigated for clinical use. One of them is coronary sinus narrowing, which is performed as a percutaneous interventional procedure using catheter-delivered device, the Reducer. The device is implanted in the coronary sinus creating a physical narrowing and a pressure gradient in the sinus. This intervention improves the impaired blood flow in the ischemic regions of the heart leading to the relief of the anginal symptoms and, therefore, the overall clinical improvement of these patients. Several clinical trials have established both the safety and efficacy of the coronary sinus Reducer, while ongoing trials are aiming to further establish the procedure's safety and efficiency in both RA and other cardiovascular diseases, such as coronary microvascular dysfunction. This review aims to discuss the pathophysiology and the role of the coronary sinus Reducer in RA, the clinical trials documenting its safety and efficacy, as well as the future perspectives of this procedure among cardiovascular diseases.

Baseline Left Ventricle Longitudinal Strain as a Predictor for Clinical Improvement Following Coronary Sinus Reducer Implantation

Coronary sinus narrowing device (reducer) implantation has emerged as an effective treatment to improve the quality of life and functional capacity in patients suffering from disabling refractory angina. Left ventricle global longitudinal strain (LV-GLS) is a useful tool for early diagnosis of subclinical cardiac injury and an independent predictor for coronary artery disease. We aimed to investigate whether LV-GLS could help predict clinical improvement after coronary sinus reducer implantation. LV-GLS assessments were performed at baseline and 6 months after reducer implantation in consecutive patients treated for refractory angina. Patients were divided into 2 groups based on reduced (<17% absolute value) or preserved baseline LV-GLS. Clinical improvement was defined as an increase of ≥25 m in the 6-minute walk test (6MWT) at follow-up. Overall, 41 patients were included, 31 in the reduced LV-GLS group and 10 in the preserved LV-GLS group. The mean age was 68 ± 8 years, with only 2 female patients (5%). Baseline characteristics did not differ significantly between the 2 groups. Univariable analysis revealed that LV-GLS was the only significant predictor for 6MWT improvement. Baseline preserved LV-GLS reduced the likelihood of 6MWT improvement by 82% (odds ratio 0.18 [0.04 to 0.83], p = 0.029). A significant increase in 6MWT (307 ± 97 m to 343 ± 92 m, p = 0.017) was observed in the reduced LV-GLS group, compared with a decrease in the preserved LV-GLS group (378 ± 86 m to 361 ± 123 m, p = 0.651). In conclusion, reduced LV-GLS may serve as a marker for potential clinical improvement in patients with refractory angina treated with reducer. Larger clinical trials are needed to establish its role.