Mitral valve replacement is a cariac surgery procedure in which a patient’s mitral valve is replaced by a different valve. Mitral valve replacement is typically performed robotically or manually, when the valve becomes too tight (mitral valve stenosis) for blood to flow into the left ventricle, or too loose (mitral valve regurgitation) in which case blood can leak into the left atrium and back up into the lung. Some individuals have a combination of mitral valve stenosis and mitral valve regurgitation or simply one or the other.