When the right ventricle of the heart contracts, the blood pressure pushes the tricuspid valve which closes and prevents a backflow of blood into the right atrium. The chordae tendineae prevents the flaps from being everted into the right atrium. Similarly, these cord-like tendons hold in position other flaps like the bicuspid or mitral valve.
Chordae tendineae are approximately 80% collagen, while the remaining 20% is made up of elastin and endothelial cells.
