The techniques of this disclosure generally relate to modular stent device and method of deploying the same. The method includes introducing a delivery system including the modular stent device via supra aortic access. The delivery system is advanced into the ascending aorta. Once positioned, the modular stent device is deployed from the delivery system such that an artery leg of the modular stent device engages the brachiocephalic artery and a bypass gate engages the aorta, wherein the artery leg partially collapses the bypass gate. The artery leg has a greater radial force than the bypass gate such that the artery leg remains un-collapsed and opened. Accordingly, blood flow through the artery leg and perfusion of the brachiocephalic artery and preservation of blood flow to cerebral territories including the brain is insured.
