During a mitral valve repair, the patient's chest is opened along the sternum (A). The heart is connected to a heart-lung machine, and an incision is made into the right atrium, or upper chamber of the heart (B), exposing the mitral valve (C). A section of the valve is removed, and the area is repaired with sutures (D and E). A flexible fabric ring may be stitched to the outside of the valve to strengthen it, in a procedure called an annuloplasty (F). (Illustration by GGS Inc.)