Modular multibranch stent assembly and method

A method comprising:

• introducing a single branch stent device via femoral access;
• advancing the single branch stent device into the ascending aorta;
• deploying the single branch stent device such that a main body of the single branch stent device engages the aorta and a branch coupling perfuses the brachiocephalic artery;
• introducing a modular stent device via supra aortic access through an artery distal of the brachiocephalic artery;
• advancing the modular stent device such that a main body of the modular stent device is located within the main body of the single branch stent device;
• and
• deploying the modular stent device such that the main body of the modular stent device engages the main body of the single branch stent device, a bypass gate of the modular stent device engages the aorta, and an artery branch of the modular stent device is located within the artery distal of the brachiocephalic artery.