The tricuspid valve guards the atrioventricular opening between the right atrium and the right ventricle of the heart. This valve is composed of three leaflets, or cusps. This valve permits blood to move from the right atrium into the right ventricle and prevents it from moving back the other way. The cusps fold out of the way when the blood pressure is greater on the atrium side, and they close whenmycontentbreak the pressure is greater on the ventricular side.