We evaluated the interaction of left atrial and ventricular diastolic performance in asymptomatic children and young adults after ToF-repair (n=25). Those young people, as well as 25 age matched healthy children and young adults were examined using non-invasive conventional echocardiography. Regional systolic and diastolic myocardial strain and strain rate in left atrium and ventricle were analysed using 2D-speckle-tracking (Vivid VII, EchoPacGE). We collected planimetric data about the left atrial and ventricular performance during systole (volumetric LVEF, LV-Tei-Index, MV-E/E'-Ratio) and diastole (LAEF, LVEDV, left atrial volume). Registration of right pulmonary-venous inflow-patterns during ventricular systole, diastole and active atrial contraction was used to support assessment of left atrial function. To verify the timing of left atrial contraction and possible electromechanical delay we measured several ECG-related time-intervals. Statistical analysis included Mann-Whitney-U-Test, Bonferroni-Holm-Test and two-tailed Spearman-Correlation. Systolic pulmonary-venous inflow in ToF-patients was not different compared to the controls. Early diastolic pulmonary-venous inflow was significantly higher in ToF-patients as well as the LV-Tei-Index. The MV-E/E'-ratio, which is closely related to LVEDP, was significantly higher in ToF-patients and correlated with the early diastolic pulmonary venous inflow parameters such as the maximum diastolic bloodflow speed. Diastolic left atrial and ventricular strain and strain rate in ToF-patients did not differ from those in the controls. During late diastole there was a significantly premature timing of maximum myocardial strain rate of the interatrial septum and time-ratio of P-wave origin to maximum reverse pulmonary-venous blood flow and the duration of one heart action. Furthermore the maximum late diastolic reverse pulmonary-venous blood flow was significantly higher in ToF-patients. Those observations indicate a premature active left atrial contraction in late diastole in ToF-patients compared to the controls. In asymptomatic young patients after ToF-repair earlier and increased left atrial contraction was found, which may indicate adaptive compensatory mechanisms to overcome latent and asymptomatic altered systolic and diastolic left ventricular performance. Extensive assessment of left atrial parameters including the pulmonary veins should be considered in terms of an entire evaluation of left heart function in patients after ToF-repair.