Abstract
There are many parameters for assessing global left ventricular function such as ejection fraction and transmitral flow. We assess global function when we want to know the severity of a disease, judge the timing of surgery and determine the prognosis of the disease. We have to choose the most suitable one from among many parameters to achieve our purpose. There are also many parameters for assessing regional left ventricular function such as wall motion and tissue velocity, although tissue velocity may be affected by whole heart motion. We want a regional parameter that can detect subtle changes in regional function because such regional changes may precede global changes. Myocardial strain can be such a parameter. Myocardial strain can be obtained by tissue Doppler echocardiography but has a limitation of Doppler angle dependency. Recent development of the speckle tracking technique facilitates easy measurements of myocardial strain irrespective of Doppler incident angle and may open new avenues for the assessment of regional function.
