There are four valves in the heart. Knowledge of the location and function of these valves will assist in yourr interpretation of heart sounds.
The right heart:
Step 1: Begin with the superior and inferior vena cavas which receive de-oxygenated blood from the body.
Step 2: Add the right atrium. The superior and inferior vena cavas empty into the first chamber of the heart, the right atrium.
Step 3: Add the tricuspid valve. Blood is held in the right atrium by the tricuspid valve. This valve is named for the three (tri) leaflets (cusps) that form the valve.
Step 4: Add the right ventricle. The tricuspid valve prevents backflow of blood from the right ventricle when the right venticle contracts (systole = S1)and opens when the right ventricle relaxes (diastole = S2) allowing blood to flow from the atrium into the ventricle prior to the next ventricular contraction.
Step 5: Add the pulmonic valve. the pulmonic valve prevents back flow from the lungs by closing during diastole and opening during systole to allow the flow of blood to the lungs.
Step 6: Rotate the 3D rendering of the heart to see the 3 semilunar (shaped like half a moon) leaflets of this valve.
