EPO and Dravet syndrome: EPO and VEGF are important in the response to hypoxia as well as promoting new blood vessels and repair of normal tissue.40–43 VEGF plays an important role in regulating angiogenesis and lymphangiogenesis.7,14 In our study, children with DS/CHD had higher EPO and lower VEGF levels at the pre- and post-operative periods than children with CHD only and pre-operatively than controls.