What is the function of chordae tendineae?

Chordae tendineae are tough, fibrous cords that attach the cusps of the heart valves (mitral and tricuspid) to the papillary muscles within the ventricles of the heart. They are responsible for preventing the valves from everting or inverting during the contraction of the ventricles, thus helping to maintain the flow of blood through the heart in one direction during each heartbeat. The papillary muscles contract at the same time as the ventricles, which causes the chordae tendineae to tense up and pull on the valve cusps, maintaining their integrity and ensuring that no blood flows backward or leaks through the valves. Damage or degeneration of the chordae tendineae can lead to valve prolapse or regurgitation, which can ultimately cause heart failure if left untreated.