#$%^&*AU2013205766A120130530.pdf#####ABSTRACT An implant assembly is implanted in vivo within a vascular system in which a vessel divides at a furcation into two sub-vessels, with smaller diameters. An implant assembly is released into a vessel e.g. a pulmonary arterial vessel. The assembly has a diameter smaller than or substantially equal to the inner diameter of the vessel and larger than the inner diameters of the sub-vessels. The implant assembly moves downstream along with the blood flow. Reaching the furcation where the vessel divides, the implant assembly is too large and not sufficiently compliant to fit through either of the smaller branch vessels, thus lodges at the furcation, prevented from moving downstream by its size and stiffness and upstream by the blood flow. Alternatively, the implant assembly, upon release, travels down a narrowing vessel until an interference fit is created between the anchor structure and the vessel wall, thereby preventing further distal movement. Fig 41110 30 F3 Fig. 2 36 46 Fig. 3 42 34 55 49 30 5