What damages the vein valves in CVI?

This question asks what harms the valves inside leg veins when someone has chronic venous insufficiency. The source answers part of it. The rest it leaves open.

A valve that cannot close

A valve that is damaged cannot close properly. That is the published starting point, and it is where this desk's answer begins and ends.

The passage behind the answer

The publisher is Cleveland Clinic. Its page on chronic venous insufficiency says:

Chronic venous insufficiency happens when the valves in your leg veins don’t work properly. Your leg veins contain valves that help your blood flow in the correct direction (toward your heart). If a valve becomes damaged, it can’t close properly.

Read it as three directives. Know that the valves steer blood toward the heart. Know that a damaged valve fails to close. Know that this failure is what the source calls chronic venous insufficiency.

The desk's reading is narrower than the question. The passage describes what a damaged valve does. It does not list what damages one. This page will not guess at causes the source does not name.

What to do next

Take the open part of the question to your treating clinician. Ask what is likely behind the valve trouble in your own legs, and whether an exam or imaging would show it.

If you want more reading first, the overview of venous disease types and symptoms is a good place to start. The encyclopedia entry on venous insufficiency gives a second description. For skin changes, see the entry on stasis dermatitis and ulcers. A fuller guide to causes, symptoms and treatment of this condition sits behind the passage above.

If you live near Westerville and want a local exam, ask for a vein evaluation rather than a general leg check.

Where the guidance stops

The source defines the problem clearly. It does not say why the valves of any one person failed. Only an exam of your legs can start to answer that.