The global myocardial function in patients after repair of tetralogy of Fallot (TOF) can be assessed by cardiovascular magnetic resonance (CMR) and measurement of B-type natriuretic peptides. Two-dimensional echocardiography-derived strain and strain rate (2D strain) facilitate the assessment of regional myocardial function. We evaluated myocardial function in 16 children with residual severe pulmonary valve regurgitation and right ventricular (RV) volume overload after TOF repair before, 1 month after, and 6 months after pulmonary valve replacement (PVR). In 2D strain echocardiography preoperatively, the longitudinal systolic RV strain was reduced (p < 0.05). One month after PVR, longitudinal systolic RV strain decreased further (p < 0.05), while systolic and early diastolic radial left ventricular strain and strain rate increased (each p < 0.05), followed by a return toward preoperative values after 6 months. Six months after PVR, preoperatively elevated RV end-diastolic volume (p < 0.01) assessed by CMR and N-terminal pro-B-type natriuretic peptide (p < 0.05) decreased. In conclusion, the impairment of the regional myocardial after TOF repair and transient changes after PVR can be subtly analyzed by 2D strain echocardiography in addition to the established assessment of myocardial function with CMR and measurement of B-type natriuretic peptides.