Role of echocardiographic studies in the ambulatory patient.

M-mode echocardiography has been extremely useful in confirming the clinical diagnosis of a wide variety of both congenital and acquired heart diseases. With the present state of the art and science of echocardiogarphy, it is the opinion of the author that M-mode coupled with phonocardiography, external arterial and venous tracings, and two-dimensional ultrasonic cardiac imaging are complementary and together provide the most information in a given patient. Two-dimensional imaging of the heart is superior in the evaluation of congenital heart disease, particularly when used in conjunction with injection of indocyanine green dye43 and with cardiac catheterization. With improvement in technology and greater clinical experience, two-dimensional ultrasound cardiac imaging will ultimately replace M-mode echocardiography in the noninvasive evaluation of cardiac disorders.