A system (1) for delivering a staple (9) to the locus of an artery (2) comprises a delivery conduit (5) for inserting into the lumen of an artery through which conduit a staple can be delivered to the locus, and an elongate element (6) such as a catheter for a balloon (7) for translating axial advancement of the delivery conduit through the artery into movement of the distal end of the delivery conduit away from the longitudinal axis of the artery and towards the artery wall.
