Coronary Sinus Reducer: An Overlooked Treatment for Stable Angina
A recent state-of-the-art review on the treatment of stable angina has sparked controversy by overlooking the coronary sinus reducer (CSR), a therapy that several cardiologists argue is both safe and effective for patients with limited treatment options. The review, conducted by the Interventional Cardiology Working Group of the Italian Society of Cardiology, focused on widely established and commercially available therapies, leaving out CSR despite its proven benefits in certain patient populations.
The Case for Coronary Sinus Reducer
Shmuel Banai, MD, from Tel Aviv Medical Center, Israel, and colleagues have highlighted the oversight in a letter to the Journal of the American College of Cardiology. They argue that CSR is the only effective therapy for patients suffering from severe, disabling angina with evidence of reversible myocardial ischemia, who have exhausted other treatment options such as coronary revascularization and optimal medical therapy.
Banai points to evidence from two randomized sham-controlled trials, COSIRA and ORBITA-COSMIC, along with meta-analyses and multiple real-life registries, demonstrating the safety and efficacy of CSR. In the ORBITA-COSMIC trial, the CSR significantly reduced symptoms at 6 months compared to a sham procedure in over 100 patients with refractory angina.
Guidelines and Ongoing Research
The European Society of Cardiology (ESC) recommends considering a reducer device for coronary sinus restriction to improve symptoms in patients with debilitating angina and obstructive coronary artery disease refractory to optimal medical and revascularization strategies (class IIb, level of evidence A). Despite these guidelines and the ongoing randomized trial in the US and Canada, CSR was not mentioned in the recent review.
The Importance of Considering All Therapies
The omission of CSR from the review raises questions about the criteria used to evaluate and include treatments in such analyses. As highlighted by a small survey conducted by ORBITA-COSMIC investigators, the perceived effectiveness of a treatment can be influenced by its mechanism's intuitiveness to physicians, potentially sidelining therapies with less obvious mechanisms despite strong evidence.
This situation underscores the need for comprehensive reviews that consider all available therapies, especially for patients with refractory conditions who have few other options. As the medical community continues to explore and validate new treatments, ensuring that all potential therapies are evaluated on their merits is crucial for advancing patient care.
