Echo enhancing agents have been used in echocardiography since 1968 for a variety of applications. Until recently, the agents were unable to survive transit through the pulmonary circulation following intravenous injection, and the technique was therefore restricted to investigations of the right side of the heart. Levovist is an echo enhancing agent capable of left heart--and even systemic--enhancement to improve the images obtained with B-mode and Doppler echocardiography. This agent offers important practical advantages in "routine" echocardiography, particularly in patients in whom image quality is suboptimal or baseline examination fails due to physical limitations. Potential future uses of contrast-enhanced echocardiography include quantitative analysis of coronary artery flow.