A coronary predilatation and stent deployment catheter assembly includes a single sheathless unitary catheter body having a proximal end and a distal end, a predilatation balloon located at the distal end of the body, and a stent inflation balloon located along the body a distance of between about 5 millimeters and about 15 millimeters proximally of the predilatation balloon. An expandable stent is disposed over the stent balloon. A predilatation balloon inflation connection is located proximally of the stent inflation balloon and in fluid communication with the predilatation balloon through a predilatation inflation lumen. A stent balloon inflation connection is located proximally of the stent inflation balloon and in fluid communication with the stent inflation balloon through a stent balloon inflation lumen. At least one radiopaque marker is disposed on the predilatation balloon and at least one radiopaque marker is disposed on the stent inflation balloon. A guidewire lumen extends through the body distal of the predilatation balloon inflation connection and extending through the body to the distal end of the body.