A stent graft assembly with a sacrificial entry/exit port is disclosed. A first sacrificial port extends from a first branch stent graft and is configured to face a second branch stent graft when the stent graft assembly is in an expanded configuration. Likewise, a second sacrificial port can be provided, and can extend from the second branch stent graft and configured to face the first branch stent graft when the stent graft assembly is in the expanded configuration. The first and optional second sacrificial ports are configured to transition between (i) an open configuration to enable a guidewire or other surgical tool to pass from the first branch stent graft to the second branch stent graft while bypassing the main body, and (ii) a closed configuration to inhibit blood flow therethrough.