Coronary sinus in the management of functional mitral regurgitation: the mother lode or fool's gold?

The past 5 years have seen the introduction into the preclinical arena of myriad devices for the potential treatment of functional and ischemic mitral regurgitation by a percutaneous approach.1 A number of the device concepts have taken advantage of the relatively easy access to the posterior annulus of the mitral valve provided by the coronary sinus. Although attractive on initial consideration as a delivery route for devices that remodel the posterior mitral annulus, a number of potential shortcomings to this approach may ultimately limit its clinical success.