Coronary sinus Reducer non-responders: insights and perspectives

Coronary sinus (CS) Reducer is currently indicated for the treatment of refractory angina in patients unsuitable for coronary revascularization. A 15-30% of non-responders is a constant across literature. Alternative coronary venous drainage systems may be an important factor in determining if patients "respond" to this intervention. We propose a simple method to indirectly assess the presence of these alternative drainage systems and predict responsiveness to Reducer implantation.