A catheter device incorporating combined ultrasound ablation and balloon dilation components. The catheter device generally comprises an elongate catheter body having proximal and distal ends and an outer surface. Disposed on the outer surface of the catheter body is a dilation balloon. At least one balloon inflation lumen fluidly connects the proximal end of the catheter body to the dilation balloon to permit injection of inflation fluid into the dilation balloon. Extending longitudinally through the catheter body is an ultrasound transmission member having a proximal end and a distal end, with the proximal end being connectable to an ultrasound transducer such that ultrasonic energy will pass through the ultrasound transmission member to the distal end thereof. In alternative embodiments of the present invention, there are provided catheter devices incorporating combined ultrasound ablation and laser ablation components as well as combined ultrasound ablation and atherectomy ablation components.