Contrast Two-Dimensional Echocardiography Provides Clinical Information Not Available with Color Flow Imaging

Contrast two-dimensional (2D) echocardiography using peripheral venous injections of agitated saline provides useful clinical information not available with standard 2D Doppler and color flow imaging techniques. Intraor extracardiac right-to-left shunting in patients with atrial or ventricular septal defects and patent ductus arteriosus can be identified in this manner, and the relative degree of shunt can be assessed. Other conditions, such as left superior vena cava to the coronary sinus or pulmonary arteriovenous malformation, are accurately detected only when contrast 2D echo is incorporated during the noninvasive examination. Recent work has also demonstrated that venous injections of agitated saline can be used to enhance continuous wave Doppler recordings of tricuspid regurgitant jet envelopes when poorly defined, or with color flow imaging to characterize the jet area. Twodimensional visualization of the needle placed in the pericardial sac for drainage of pericardial effusion may be difficult. Injection of agitated saline through the needle may be used to verify proper location in the pericardial sac and not in the ventricular chambers. The role of contrast 2D echocardiography with new agents has been used to assess myocardial perfusion. All of these applications of contrast echo contribute to standard echocardiographic techniques to provide a better characterization of flow dynamics not seen with color flow imaging.