The Echocardiogram

Abstract
THE first medical application of ultrasound was reported in 1942, when Dussik1 tried to outline the ventricles of the brain. Since then, the biophysical characteristics and the clinical safety requirements of ultrasound have been defined, and this technic has been used diagnostically and therapeutically in a variety of diseases.2 The application of ultrasound in cardiology dates back to 1950, when Keidel3 attempted to measure volume changes in the heart by directing an ultrasound beam through the chest. Subsequent studies by other investigators indicated the potential usefulness of ultrasound in the evaluation of mitral-valve disease4 , 5 and in the detection of atrial . . .