A medical apparatus and method for remodeling a mitral valve annulus adjacent to the coronary sinus includes an elongate body having a proximal end and a distal end. A neck, spine and spinal cord support device of a semi-rigid material is removably insertable in the pocket of the blanket body and secured within the blanket by the pocket so as to maintain the support device in a substantially fixed position within the blanket body. Preferably, the excimer laser is controlled in consideration of how well the at least one conductive layer absorbs radiation at particular wavelengths.