From the AHA Guidelines Site and JAMA...
Best wishes,
1 Bonow RO, et al. (1998). ACC/AHA guidelines for the management of patients with valvular heart disease: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients With Valvular Heart Disease). Journal of the American College of Cardiology, 32(5): 1486?1588.Once you have symptoms, if you don't have the valve replaced, you may dramatically shorten your life. About 75% to 80% of people who have symptoms of severe aortic valve stenosis die within 3 to 5 years if they do not have valve replacement surgery. In contrast, most people who have valve replacement have a normal life expectancy1
Best wishes,