Fig. 1. Anatomical details of the surgical implantation of a cannula in the sinus venosus. (A) Schematic drawing showing the position of insertion in the V^th gill arch. (B) Picture showing the thin-walled left duct of Cuvier (LDC) bulging from the incision site. (C) Picture showing the two silk snares in place before the cannulation. The tied snare (top one) is used to pull the vessel wall during the procedure, the untied snare (bottom one) is used to secure the cannula to the LDC after insertion.