The Cardiac Valves:
The 4 cardiac valves, two A-V and two semilunar, develop from the endocardial tissue, guaranteeing unidirectional flow of blood (Figure 2.06). The A-V valves develop from endocardial cushions at the A-V canal, while the semilunar valves (aortic & pulmonic) develop from endocardial tissue involved in the spiral separation just described, and secondary mounds on the opposite sides of the channels.
To review adult heart structure