[Innovative therapies for the treatment of refractory angina: the Reducer, a percutaneous device to narrow the coronary sinus].

Refractory angina is a chronic condition characterized by the presence of disabling symptoms due to severe obstructive coronary artery disease that is not improved by a combination of medical therapy and percutaneous or surgical revascularization. Mortality rates associated with this condition are quite low in clinically stable patients on optimal medical therapy, but rehospitalization rates remain high. This mandates the need for new therapies targeting an improvement of symptoms in this population, taking into account also the potential impact in terms of healthcare and costs. The increase in coronary sinus pressure seems to reduce myocardial ischemia leading to a redistribution of blood flow to the ischemic territories. The coronary sinus Reducer is a percutaneous implantable device, made of a stainless steel hourglass-shaped stent, designed to achieve controlled narrowing of the coronary sinus and to increase its upstream pressure. In various studies, the Reducer was safely implanted percutaneously via the right jugular vein in patients with refractory angina who were not amenable to revascularization and was associated with an improvement in anginal symptoms and ischemia. These results support further evaluation of the Reducer as an alternative treatment for patients with chronic refractory angina who are not candidates for coronary revascularization.