National Heart, Lung, and Blood Institute (NHLBI) - The heart has four valves: tricuspid, pulmonary, mitral, and aortic. If one or more of these don't work, this is known as heart valve
What Is Heart Valve Disease? | Oklahoma Heart Institute
Heart Valve Disease
Different Valves in Heart & Their Function - Dr Hamdulay
What is a Aortic Valve - Montefiore Einstein Center for Heart and Vascular Care