Valvular heart disease is a condition that affects the valves of the heart, causing them to become damaged or malfunctioning. There are several synonyms that can be used to describe this condition, including mitral valve prolapse, aortic stenosis, and mitral regurgitation. Mitral valve prolapse occurs when the valve between the heart's two left chambers doesn't close properly, while aortic stenosis refers to the narrowing of the valve that controls blood flow out of the heart. Mitral regurgitation is when the valve between the heart's left atrium and left ventricle doesn't close tightly, causing blood to leak back into the atrium. Other synonyms for valvular heart disease include tricuspid stenosis, pulmonic stenosis, and mitral stenosis.