Echocardiography as an index of cardiac performance.

Ultrasound imaging of the heart provides a noninvasive technique for assessing cardiac performance and diagnosing a wide range of disorders. Recent improvements in two-dimensional, planar instrumentation promise to make echocardiography even more versatile, permitting more comprehensive views of left ventricular function, valve orifice areas, and the spatial relationships of the great vessels and ventricular chambers.