Functional anatomy of heart

1- Functional anatomy of heart.
Objectives:
1. Explain the functions of the heart.
2. Describe the flow of blood through the heart.
3. Explain the functions of the heart valves.
Heart chambers and function of valves:
The heart acts as two separate pumps, right and left sides. There are four valves in the heart; two are called atrioventricular valves (mitral and tricuspid valves). These valves open during ventricular diastole to allow blood to fill the ventricles and close during ventricular systole. Other two valves are called semilunar valves (aortic and pulmonary valves). These valves open during systole to allow eject blood from the ventricles into the aorta or pulmonary artery and close during diastole. See figure 1.
Papillary muscles that attach to the vanes of the A-V valves by the chordae tendinae, contract when the ventricular walls contract. They pull the valves inward toward the ventricles to prevent their bulging too far backward toward the atria during ventricular contraction. If chordae tendinea becomes ruptured or paralyzed the valve bulges far backward. See figure 2.