One-Way Valves Become Weakened or Damaged
Veins have one-way valves to channel blood back to your heart. Varicose veins develop when the valves of your veins become weakened or damaged.
Causes of Weakness or Damage
- High blood pressure inside the superficial leg veins
- Standing for long periods of time
- Weakness in the walls of the veins
Blood Pooling Becomes Visible Below Skin
When the valves become weakened or damaged, blood pools in the veins, enlarging them and often making the veins just below the skin visible.
There is also a strong genetic component.