Which structures prevent valve cusps from everting during ventricular contraction?

Which structures prevent valve cusps from everting during ventricular contraction?

• A. Papillary muscles
• B. Chordae tendineae
• C. Aortic valve leaflets
• D. Interventricular septum

Answer: (B)

During ventricular contraction the valves between the atria and ventricles must stay closed to prevent backflow. The chordae tendineae attach each valve cusp to papillary muscles inside the ventricle. As the ventricle contracts, the papillary muscles pull on these cords, keeping the cusps taut and preventing them from flipping upward into the atria. This tethering preserves one-way flow and resists cusp prolapse. If the chordae are damaged or rupture, the cusps can prolapse and cause regurgitation. The papillary muscles help by pulling on the cords, but the direct restraint comes from the chordae tendineae. The aortic valve leaflets and the interventricular septum don’t perform this function.

During ventricular contraction the valves between the atria and ventricles must stay closed to prevent backflow. The chordae tendineae attach each valve cusp to papillary muscles inside the ventricle. As the ventricle contracts, the papillary muscles pull on these cords, keeping the cusps taut and preventing them from flipping upward into the atria. This tethering preserves one-way flow and resists cusp prolapse. If the chordae are damaged or rupture, the cusps can prolapse and cause regurgitation. The papillary muscles help by pulling on the cords, but the direct restraint comes from the chordae tendineae. The aortic valve leaflets and the interventricular septum don’t perform this function.