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Formation of a blood clot in a vein

Normal blood flow

Cross section of vein, showing blood flowing normally through valve
slide 1 of 3
slide 1 of 3, Normal blood flow,

Normally, one-way valves in the veins keep blood flowing to the heart.

Blood clot forming

Blood clot forming
slide 2 of 3
slide 2 of 3, Blood clot forming,

A blood clot can form when the valve in a vein does not work properly. If the valve does not open normally, blood cells can collect behind the valve and begin to stick together to form a clot.

Formed blood clot

Cross section of a vein, showing blood clot formed around valve
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slide 3 of 3, Formed blood clot,

When a blood clot gets large enough, it can stop the flow of blood in the vein.

Current as of: August 6, 2023

Author: Healthwise Staff
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