Embodiments of the invention relate to a catheter having an ultrasound energy emitting region that is both rotatable about and slidable along the shaft of the catheter. One embodiment is directed to a catheter comprising an ultrasound transducer coupled to the shaft, and at least one actuator coupled to the handle and the ultrasound transducer that is adapted to move the ultra-sound transducer both longitudinally along the shaft and circumferentially about the shaft. Another embodiment of the invention is directed to a catheter comprising an ultrasound transducer coupled to the shaft, and at least one actuator that is adapted to move the sheath both longitudinally along the shaft and circumferentially about the shaft to orient a window of the sheath in a desired position.