Balloon catheters, and medical devices including balloon catheters, are provided that comprise a balloon assembly disposed at the distal end of an elongated tubular member. The balloon, when in the inflated state, includes a body fluid lumen that extends longitudinally through the balloon and is open at the proximal end of the balloon and the distal end of the balloon. In some aspects, the outer surface of the balloon is contiguous from the proximal end to the distal end of the balloon when the balloon is inflated. In other aspects, an endoluminal prosthesis, for example, a stent that can optionally include a prosthetic valve, surrounds the balloon assembly and is adjacent to the outer surface of the balloon. In still other aspects, endoluminal prosthesis implant devices are provided that are suitable for implanting an endoluminal prosthesis in a body vessel containing a flowing fluid such as a vessel in the heart, e.g., the left or right ventricle inflow or outflow tracks. The endoluminal prosthesis implant