Complications are rare but bleeding, infection, superficial or deep vein thrombosis (clotting), and paresthesia (numbness) can occur. Thankfully all are very uncommon. There are literally thousands of superficial veins in the legs. Following endovenous ablation, blood simply returns to the deep vein and back to the heart, resulting in much healthier circulation. There is much less pressure on the deep vein because the total volume of blood in the legs is less without the reflux and pooling caused by diseased superficial veins.