Chordae tendineae

Definition

Chordae tendineae are fibrous strings that connect the papillary muscles to the atrioventricular (AV) valves in the heart, specifically the mitral and tricuspid valves. These tendinous cords play a critical role in maintaining the integrity of the heart's valve system by preventing the valves from inverting or prolapsing during ventricular contraction. This ensures proper blood flow direction through the heart, showcasing the intricate design of cardiac structures.

5 Must Know Facts For Your Next Test

1. The chordae tendineae are often referred to as 'heart strings' due to their appearance and function.
2. They are made up of collagen and elastin fibers, providing strength and flexibility to withstand the forces generated during heartbeats.
3. Chordae tendineae help prevent conditions such as mitral valve prolapse, where a valve may fail to close properly, leading to regurgitation.
4. There are multiple chordae tendineae for each AV valve, allowing for a more secure connection and better distribution of forces during contraction.
5. Damage or rupture of chordae tendineae can lead to serious cardiac conditions, requiring medical intervention like valve repair or replacement.

Review Questions

• How do chordae tendineae contribute to the overall function of atrioventricular valves during ventricular contraction?
  • Chordae tendineae connect the papillary muscles to the atrioventricular valves, preventing these valves from inverting as the ventricles contract. During contraction, increased pressure within the ventricles could force the valves backward; however, the chordae tendineae maintain proper valve positioning, ensuring one-way blood flow from the atria to the ventricles. This mechanism is crucial for efficient heart function and maintaining hemodynamic stability.
• Discuss the structural relationship between chordae tendineae, papillary muscles, and atrioventricular valves in maintaining proper cardiac function.
  • The chordae tendineae serve as a critical link between papillary muscles and atrioventricular valves. The papillary muscles contract along with ventricular contraction, pulling on the chordae tendineae. This action keeps the AV valves closed against high ventricular pressure while simultaneously allowing them to open fully when needed. This coordination prevents backflow and supports efficient blood circulation through both sides of the heart.
• Evaluate the potential clinical implications if chordae tendineae are damaged or dysfunctional and how this might affect cardiovascular health.
  • Damage or dysfunction of chordae tendineae can lead to significant cardiovascular issues such as valve regurgitation or prolapse. When these structures fail, it can result in improper closure of atrioventricular valves during ventricular contraction, allowing blood to flow backward into the atria. This condition can lead to symptoms like fatigue and shortness of breath due to decreased cardiac efficiency. In severe cases, surgical intervention may be necessary to repair or replace affected valves, highlighting the importance of these structures in maintaining healthy heart function.

Related terms

Papillary Muscles: Muscle projections located in the ventricles of the heart that anchor the chordae tendineae and help control the opening and closing of the AV valves.

Atrioventricular Valves: The valves located between the atria and ventricles, including the mitral and tricuspid valves, which ensure one-way blood flow within the heart.

Ventricular Contraction: The phase of the cardiac cycle where the ventricles contract to pump blood out of the heart, leading to increased pressure that affects valve function.