Alterations of left ventricular mechanics after anterior myocardial infarction: Quantitative analysis by tissue Doppler echocardiography.

Myocardial ischemia is usually responsible for alterations of regional left ventricular function which are not quantified by routine echocardiography. We used tissue Doppler echocardiography to quantitate the three main compo nents (radial, longitudinal and angular) of left ventricular function, and their alterations after acute anterior myocardial infarction. Radial function was assessed by the myocardial velocity gradient derived fr om M-mode color tissue Doppler echocardiography, and longitudinal function by the pulsed wave tissue Doppler echocardiography, in 26 patients who expe rienced a first acute anterior myocardial infarction and in 11 matched heal thy subjects. We describe a new tissue Doppler method for the measurement o f septal angular deformation during cardiac contraction. In healthy subject s, our results showed heterogeneous regional myocardial contraction. Septal angular deformation occurred in the same direction and was of the same ord er as predicted by previous MRI studies. After anterior infarction, systoli c and diastolic myocardial velocity gradients were dramatically decreased i n the anterior wall when compared with controls (p < 0.01), whereas the sys tolic velocity gradient was significantly higher in the opposite wall (p < 0.05). Pulsed wave tissue Doppler echocardiography revealed significant alt erations of longitudinal left ventricular function. Septal angular deformat ion was decreased after anterior infarct, and a good correlation was found between the angle of rotation and the left ventricular ejection fraction by cineangiography. These results indicate that tissue Doppler echocardiography has the potenti al for measuring the three main components of regional left ventricular fun ction, and for quantitatively assessing their functional alterations induce d by acute myocardial ischemia.