Chung Sim Lim1, Moushumi Baruah2, Sandeep S Bahia3. 1. Department of Vascular Surgery, Royal Free London NHS Foundation Trust, London NW3 2QG, UK cslim@doctors.org.uk. 2. Burney Street Practice, Greenwich, London SE10 8EX, UK. 3. St George's Vascular Institute, St George's University Hospitals NHS Foundation Trust, London SW17 0QT, UK.