An endograft comprising a proximal end and a distal end is disclosed. The endograft includes a tube of biocompatible material. The tube includes a main lumen extending longitudinally from the proximal end to the distal end, the main lumen including a proximal portion, an intermediate portion and a distal portion; a branch lumen within the intermediate portion of the main lumen; and a seam, the seam extending longitudinally beside both the branch lumen and the distal portion of the main lumen, wherein the tube includes a lateral cross-section defining a tubular wall pinched together by the seam to form a branch portion. The branch portion includes an entrance within the intermediate portion of the main lumen and an exit through the tubular wall of the main lumen.