Cardiac imaging techniques: which, when, and why
JAMES D. THOMAS, MD
BRIAN P. GRIFFIN, MDAddress reprint requests to B.P.G., Department of Cardiology, F15, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195.
RICHARD D. WHITE, MD
Although a variety of cardiac imaging methods are available, their effective use requires knowledge of their underlying principles, clinical applications, potential pitfalls, and expense. This review outlines, for the generalist, the basics of echocardiography, nuclear imaging, and magnetic resonance imaging (MRI) and provides insight into their appropriate use.KEY POINTS
Two-dimensional echocardiography provides a highly detailed image of cardiac structure and function, and is particularly useful in assessing global and regional left ventricular contraction, valvular morphology, and congenital abnormalities.
Doppler echocardiography allows evaluation of the velocity, direction, and turbulence of blood flow.
Transesophageal echocardiography provides extremely high-resolution images, particularly of structures around the cardiac base.
Echocardiography during cardiac stress testing can demonstrate regional wall-motion abnormalities that evolve under increasing metabolic demands on the heart.
Nuclear imaging techniques are useful in delineating normally perfused tissue from tissue that is either underperfused or nonviable.
Positron-emission tomography can image the heart with very great accuracy.
Magnetic resonance imaging provides highly detailed, three-dimensional images.