2003 Volume 1 Issue 1 Pages 29-42
The widespread use of the pulsed Doppler echocardiography has facilitated the noninvasive evaluation of hemodynamic abnormalities of the left atrium and left ventricle (LV) based on transmitral and pulmonary venous flow velocity patterns. However, it has been shown that loading conditions, especially preload, influence the indices obtained from these velocity patterns. Recently, tissue Doppler imaging (TDI) has been applied to the clinical setting to assess LV myocardial function. In particular, this procedure has the following characteristics: 1) it can provide circumferential and longitudinal information for the LV myocardium; 2) the early diastolic LV myocardial parameters determined by TDI are not influenced by preload; 3) LV myocardial contractility can be evaluated from the early systolic parameters; 4) LV systolic and diastolic asynchrony can be detected; 5) myocardial velocity gradients obtained from color-coded TDI are not influenced by the entire heart motion; and 6) TDI parameters are useful for establishing the prognosis of patients with LV heart failure. In the future, technologic improvements will elucidate the tissue characteristics based on tissue velocity information in patients with myocardial disease or allow the detection of endocardial and/or epicardial involvement of the LV myocardium in patients with ischemic heart disease.