The purpose of this study is to find out if an approved medicine that is used to lower cholesterol called Lipitor can slow or stop progressive narrowing of the aortic heart valve in patients with a condition called aortic stenosis. Patients who have aortic stenosis who volunteer for this study will take Lipitor for 2 years and will undergo a brief exam by a physician, labwork to measure cholesterol, and a routine heart ultrasound (sound picture of the heart) at the start of the study and every 6 months, stopping at 2 years.