An angioplasty apparatus for facilitating accurate placement of a lumen stent for dilating a stenosis, the apparatus includes arcuate low pressure balloon segment(s) connected at a distal end of a guiding catheter with gap(s) to facilitate blood flow during a stenting procedure. Optimal positioning of a stent at a lumen bifurcation is facilitated to obviate any tendency of a stent to miss a proximal end of a stenosis branch lumen while concomitantly preventing the stent from protruding into an original lumen, such as a patient's aorta.
