T e four heart valves reside in the center of the heart. T is indicates their crucial role in cardiac performance. Fau- less function of the valves is a prerequisite for unidir- tional forward movement of the blood, and such function is necessary to support the ef orts of the cardiac atria and ventricles. Healthy heart valves function gracefully and of er mechanical durability. Bioengineers have to marvel at the biomechanical evolution of these perfectly placed valves. Heart valves can be involved in pathological processes, however, and only then do we realize just how indispensable they...