A inflatable catheter balloon for placement of a stent in the curved segment of the aortic arch for treatment of coarctation of the aorta is constructed having an inflated curved structure mounted off-center on a pre-curved shaft to create unequal balloon lengths on opposing sides of the shaft. In an alternate construction the balloon is curved and constructed having a convex surface and a concave surface wherein the convex surface is longer than its concave side. In another alternate construction two inflatable balloons are mounted on opposing sides of the pre-curved shaft. The longer balloon has a steeper taper at its opposing ends than the shorter of the two balloons. The longer balloon has its fluid-filling opening located at one of its two tapered ends. The shorter balloon has its fluid-filling opening located in the center section of the balloon.
