Mechanism of Action The Pro-V laser uses a 1319 nm wavelength, the optimal wavelength for fast and comfortable endovenous laser ablation. Absorption of laser light occurs in water within the vein and vein wall, and the heat generated by absorption of laser energy contracts and collapses the vein wall. This halts the formation of future varicosities and results in complete vessel closure. With blood flow to the insufficient vein interrupted, the pooling and bulging that causes varicose veins will begin to subside. The ablated vein is absorbed by the body and blood circulation redirects itself to healthy veins. Endovenous Ablation Results