A cannula having a proximal end, a distal end, and a lumen extending between the proximal and distal ends is provided. The diameter of the lumen of the cannula can be varied to take into account differences in the diameter of access and target vessels during cannulation. The cannula is further characterized...http://www.google.fr/patents/US7967776?utm_source=gb-gplus-shareBrevet US7967776 - High performance cannulas
