Fig. 9.

Navi-Bossing technique. Antegrade and retrograde catheter/guidewire systems are in two separate subintimal planes. An antegrade Navicross catheter (Terumo, Somerset, NJ) is rotated slightly in one direction and then the other and at the same time advanced back and forth in the chronic total occlusion on each side of the guidewire from below. This disrupts the tissues between both subintimal planes eventually allowing through and through access of the wire and/or 0.018-inch catheter from below. The retrograde wire or catheter/wire system can then be externalized through the 4-Fr Navicross catheter.