Once regarded as “noise”, the Doppler shift recorded from moving myocardium provides a great deal of information about cardiac function and forms the basis of tissue Doppler imaging (TDI). TDI is rapidly becoming a routine part of echocardiographic evaluation of the heart. Given the large amplitude signal obtained with TDI, recordings of myocardial velocities are technically easy to acquire and they provide reproducible, quantitative measurements even when 2- dimensional images are suboptimal. Although TDI has broad potential utility in cardiac functional assessment, its most rigorously validated applications include: 1) estimation of left ventricular filling pressures; 2) assessment of systolic and diastolic function; 3) quantification of ventricular dyssynchrony and evaluation for cardiac resynchronization therapy; and 4) detection of myocardial ischemia or segmental contractile dysfunction. Here we highlight some of the fascinating discoveries that led to the development of TDI and discuss its clinical application in each of these areas. Because TDI is such a powerful means of noninvasively assessing cardiac physiology and pathophysiology, its application in clinical practice will undoubtedly continue to increase as it is becomes more widely understood.
Keywords: Tissue doppler imaging, mechanical dyssynchrony, ischemia, regional contraction, diastole, hemodynamic assessment