Surgical treatment

I am a 38 years old female and I have had vein reconstruction on my right leg in 2001 and on my left leg in 2003. The veins in the left leg are leaking again and the doctor wants to repair the valve, not just the vein. The insurance company won't pay for the valve repair, because they say it's not necessary. My doctor tells me if I just have the vein repaired, I'll be back in another surgery within a year. What will happen if I don't have the surgery on the veins. Can you tell me what my worse case scenario might be.