There are two types of valves: Atrialventricular, which control the flow of blood from atria (small chambers of the heart) to ventricles (large chambers of the heart). These are the mitral valve (from the left atrium to the left ventricle) and the tricuspid valve (from the right atrium to the right ventrical) Semilunar, which control the flow of blood from the ventricles to the arteries. These are the pulmonary valve (to the pulmonary artery) and the aortic valve (to the aorta)