Blood has to flow through a smaller opening, so less blood gets through the valve into the next chamber. The valve's supportive structures may be loose or torn. Or, the valve itself may have stretched or thinned. Blood may then leak back the wrong way through the valve. During heart valve surgery, one or more valves are repaired or replaced.
Repair means that the valve is mended to help it work better.
Replacement means your diseased valve is removed and a new valve is inserted in its place. Whether a valve will be repaired or replaced can only be decided once surgery has begun. Your surgeon will talk with you about his or her plans for surgery and any other procedures you may need. Repairing a Valve During valve repair, a ring may be sewn around the opening of the valve to tighten it. Other parts of the valve may be cut, shortened, separated, or made stronger to help the valve open and close right.