Aortic valve disease refers to any condition affecting the valve that controls blood flow from the heart's left ventricle into the aorta. Synonyms for this condition include aortic stenosis, aortic regurgitation, and aortic valve insufficiency. Aortic stenosis is characterized by a narrowing of the aortic valve, while aortic regurgitation occurs when blood leaks back into the heart from the aorta. Aortic valve insufficiency refers to a combination of both aortic stenosis and regurgitation. Although these synonyms describe different aspects of the same condition, they all ultimately involve abnormalities in the functioning of the aortic valve, which can lead to serious health complications if left untreated.