A method of deploying a stent graft in a blood vessel with at least one side branch vessel, comprising: (a) forming a blood flow conduit between the branch vessel and the blood vessel such that a vessel section of the conduit is axially located inside the blood vessel and a branch section is positioned inside the branch vessel (b) deploying the stent graft inside the blood vessel so that blood flow into said at least one side branch is blocked by the stent graft and continues through the blood flow conduit (c) forming an opening suitable for allowing blood flow between the blood vessel and the branch vessel and (d) interrupting blood flow in the vessel section of the conduit.
