How Chordae Tendineae and Papillary Muscles Control Heart Valve Closure

Heart valves open and close due to pressure differences between chambers. The valves consist of leaflets anchored by chordae tendineae—thin, fibrous cords connected to papillary muscles in the ventricles.

During ventricular contraction (systole), papillary muscles contract, pulling the chordae tendineae, which prevent valve leaflets from prolapsing backward, thus ensuring one-way blood flow.

There are no tendons connecting muscles to bones in the heart; the chordae tendineae serve a similar anchoring function but are distinct structures.