The EkoSonic Endovascular System employs high frequency (2-2.5 MHz), low power (0.585 watt average power per transducer) ultrasound to facilitate the delivery of physician-specified fluids in the peripheral vasculature and to deliver solutions into the pulmonary arteries. || The EkoSonic Endovascular System is intended for the controlled and selective infusion of physician-specified fluids, including thrombolytics, into the peripheral vasculature and the infusion of solutions into the pulmonary arteries. The reusable EKOS EkoSonic Control Unit provides power to the system and the user interface for operator control. A reusable, non sterile Connector Interface Cable connects the EKOS EkoSonic Control Unit to the EkoSonic Endovascular Device.