2 questions. Aortic stenosis w/o symptoms has good prognosis. Symptomatic as has 5, 3, and 2 yr life expectancy depending on symptoms. Chest pain (5), passing out (3) and heart failure (2) yrs. This improves if the valve is replaced. Mitral valve prolapse does not significantly affect your prognosis by itself. Some though can worsen and begin to leak. This can also lead to heart failure.
Depends. Sometimes surgery can correct depending on your general health status.