1 From the Charing Cross Hospital (M.S., G.S., S.M.), Imperial College Healthcare NHS Trust; and Chelsea and Westminster Hospital (M.S., G.S., S.M.), Chelsea and Westminster Hospital NHS Foundation Trust, London, UK.
2 From the Charing Cross Hospital (M.S., G.S., S.M.), Imperial College Healthcare NHS Trust; and Chelsea and Westminster Hospital (M.S., G.S., S.M.), Chelsea and Westminster Hospital NHS Foundation Trust, London, UK. stephen.murphy22@nhs.net.