Systems, methods, and catheters for endovascular treatment of a blood vessel

In one aspect, a system for endovascular treatment of a blood vessel includes a control unit, an ultrasound device, an actuator, and a catheter having a treatment portion. The ultrasound device is communicatively coupled to the control unit. The ultrasound device includes an ultrasound probe having a subject contact surface. The actuator is coupled to the ultrasound probe and is operable to move the subject contact surface of the ultrasound prove relative to a treatment zone of a subject. The control unit is configured to determine a position of the treatment portion of the catheter as the catheter is advanced through the blood vessel, and move the subject contact surface of the ultrasound probe relative to the treatment zone of the subject with the actuator to follow the position of the catheter as the catheter is advanced through the blood vessel.