Question: what are the structural differences between the atrioventricular and semilunar valves?
Answer: Valve anatomy is complex (Figure 1). The mitral and tricuspid atrioventricular (AV) valves separate the atria from the ventricles, while the aortic and pulmonary semilunar (SL) valves separate the ventricles from the great arteries. AV valves have leaflets and SL valves have cusps.