An improved stent design and stent delivery catheter assembly for repairing a main vessel and a side branch vessel forming a bifurcation. The stent is advanced to a bifurcation so that the main stent section is in the main vessel, and the portal section covers at least a portion of the opening to the side branch vessel. A low profile catheter having a branch with an inflation balloon and a balloon-less branch are maintained in a joined configuration during delivery of the catheter to the deployment site. Radiopaque markers on the balloon and on the balloon-less shaft enable the longitudinal and rotational orientation of the assembly to be fluoroscopically envisioned. The inflation of the balloon causes the stent to be expanded while the presence of the balloon-less shaft causes the stents side portal to be opened sufficiently to allow for a subsequent expansion procedure.