What are the structures that connect the AV valves to the papillary muscles?

The chordae tendineae are the structures that connect the atrioventricular (AV) valves to the papillary muscles. These fibrous cords play a critical role in the heart's function. When the ventricles contract, the pressure increase causes the AV valves to close, preventing backflow of blood into the atria. The chordae tendineae help maintain tension on the valve leaflets, ensuring they remain sealed during ventricular contraction. The papillary muscles, which are attached to the ventricular walls, contract simultaneously with the ventricles, pulling on the chordae tendineae to prevent the valves from prolapsing into the atria. This coordinated mechanism is essential for maintaining proper blood flow direction and heart efficiency during the cardiac cycle.

Other options do not fulfill this role: coronary arteries supply blood to the heart muscle itself, septal bands are structures associated with the electrical conduction system, and suspensory ligaments are not relevant in the context of heart valve function.