Anatomical basis of retrograde thoracic veins flow and its implications in complex thoracic wall reconstructive surgery.

Purpose: Internal thoracic veins are increasingly used as recipient's vessels in chest wall reconstructive surgery due to their predictable anatomy and to the possibility to make a double venous anastomosis, exploiting the retrograde flow within them. Over the years, retrograde flow had been explained by the absence of valves in internal thoracic veins, which have been found recently instead. Therefore, our aim is to analyze the retrograde flow and its relationship with valves in the internal thoracic veins.