In order to compare the ECG patterns to several echocardiographic morphological indexes in different left ventricular overloadings, 15 cases of systolic left ventricular overloading (SLVO) and 17 cases of diastolic left ventricular overloading (DLVO) were analyzed. The current ECG changes of left ventricular hypertrophy and some original parameters of ventricular repolarization have been correlated with volumes, ejection fraction and mass of the left ventricle (calculated by Reichek's formula) and with left ventricular diastolic and systolic eccentricity indexes, derived by the application of Fishl's formula to the 2D echocardiographic four or two chamber apical view. In both SLVO and DLVO we found a correlation between the left ventricular mass and Romhilt-Estes point score system (p = 0.02) as well as the degree of ventricular repolarization abnormalities (p = 0.01). In SLVO we found a direct correlation between negative P wave deflection on lead V1 and diastolic as well as systolic eccentricity index: that is, the more negative P wave the more elongated left ventricular geometry. Moreover, in SLVO we found an interesting apposite correlation, compared with DLVO, between the systolic eccentricity index and the degree of ventricular repolarization abnormalities: in SLVO ST depression or T wave inversion on left limb or left precordial leads was associated with the maintenance of an elongated shape of left ventricle, while in DLVO the same ventricular repolarization abnormalities were associated with the loss of the elongated geometry of left ventricle which became spheric. Thus ECG correlates with echocardiographic left ventricular mass if poliparametric voltage indexes are considered.(ABSTRACT TRUNCATED AT 250 WORDS)