Important advances in technology: echocardiography.

Echocardiography has evolved over the past 45 years from a simple M-mode tracing to an array of technologies that include two-dimensional imaging, pulsed and continuous wave spectral Doppler, color flow and tissue Doppler, and transesophageal echocardiography. Together, these modalities provide a comprehensive anatomic and functional evaluation of cardiac chambers and valves, pericardium, and ascending and descending aorta. The switch from analog to digital signal processing revolutionized the field of ultrasound, resulting in improved image resolution, smaller instrumentation that allows bedside evaluation and diagnosis of patients, and digital image storage for more accurate quantification and comparison with previous studies. It also opened the door for new advances such as harmonic imaging, automated border detection and quantification, 3-dimensional imaging, and speckle tracking. This article offers an overview of some newer developments in echocardiography and their promising applications.