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The assessment of regional left ventricular (LV) function has been an important yet unresolved problem since the introduction of echocardiography as a diagnostic tool. Abnormal regional LV wall motion is an early finding in multiple cardiac pathologies and its diagnosis is of critical importance. In the last few years diagnostic procedures based on combined use of existing echocardiographic technologies were geared toward improving the accuracy of detection of baseline and/or induced regional wall motion abnormalities. One of the assumptions is that the combination of reduced LV wall thickening and reduced myocardial velocities can be used to accurately diagnose regional myocardial dysfunction. In this article we will discuss several new techniques for the quantification of regional LV function using Doppler echocardiography.

Pulsed-wave Doppler tissue imaging (DTI) allows the examination of regional wall motion at a very high temporal resolution and therefore constitutes an excellent technique for assessing diastolic motion of left ventricular walls. Regional relaxation has been well characterized in normal subjects using this technique, and physiological time intervals and motion wave profiles are described. In an experimental model of acute ischemia, local relaxation impairment was observed showing highly characteristic local diastolic abnormalities. Interestingly, these findings took place before any decrease in systolic motion was recordable. In a prospective clinical study, noninvasive regional DTI parameters were compared with coronary angiography to assess the feasibility and clinical value of the technique; the diagnostic accuracy is discussed in detail. Also, the association between regional diastolic parameters and global regional function as assessed by Doppler analysis of transmitral left ventricular filling flow was studied, stressing the impact of regional diastolic function on overall ventricular performance. Finally, the diagnostic role of pulsed-wave DTI on stress testing, identification of myocardial viability, and microvascular angina is reviewed.