Rupture of chordae tendineae:

Options

A. Help the A-V valve to close
B. Prevent the bulging of A-V valve into the atria during contraction
C. Causes regurgination of blood into the atria during ventricular systole
D. Has no effect on haemodynamics of circulation

Answer

**Step-by-Step Solution:**

1. **Understanding Chordae Tendineae**: The chordae tendineae are cord-like structures that connect the atrioventricular (AV) valves (mitral and tricuspid valves) to the papillary muscles in the ventricles. They play a crucial role in the functioning of the heart by preventing the valves from inverting during ventricular contraction.

2. **Function of Chordae Tendineae**: The primary function of the chordae tendineae is to prevent the eversion (bulging) of the AV valves into the atria when the ventricles contract. This ensures that blood flows in the correct direction—from the atria to the ventricles and then out to the body or lungs.

3. **Effect of Rupture**: If the chordae tendineae rupture, they can no longer effectively support the AV valves. This leads to the inability of the valves to close properly during ventricular systole (the contraction phase of the heart).

4. **Consequences of Rupture**: The rupture results in regurgitation, which is the backflow of blood into the atria during ventricular contraction. This means that instead of blood being pushed out of the heart, some of it flows back into the atria, leading to inefficient circulation.

5. **Conclusion**: Therefore, the correct answer to the question regarding the effects of the rupture of chordae tendineae is that it causes regurgitation of blood into the atria during ventricular systole.

**Final Answer**: The rupture of chordae tendineae causes regurgitation of blood into the atria during ventricular systole.

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