[Alterations of left ventricular mechanics after anterior myocardial infarction. Quantitative analysis by tissue...

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 components (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 from M-mode color tissue Doppler echocardiography, and longitudinal function by the pulsed wave tissue Doppler echocardiography, in 26 patients who experienced a first acute anterior myocardial infarction and in 11 matched healthy subjects. We describe a new tissue Doppler method for the measurement of septal angular deformation during cardiac contraction. In healthy subjects, our results showed heterogeneous regional myocardial contraction. Septal angular deformation occurred in the same direction and was of the same order as predicted by previous MRI studies. After anterior infarction, systolic and diastolic myocardial velocity gradients were dramatically decreased in the anterior wall when compared with controls (p < 0.01), whereas the systolic velocity gradient was significantly higher in the opposite wall (p < 0.05). Pulsed wave tissue Doppler echocardiography revealed significant alterations of longitudinal left ventricular function. Septal angular deformation 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 potential for measuring the three main components of regional left ventricular function, and for quantitatively assessing their functional alterations induced by acute myocardial ischemia.