The aim of the study was to assess residual sequels in children after tetralogy of Fallot surgical repair (rTOF).

Patients and Methods:
The study group (SG) consisted of 52 patients, mean age 13.7 ± 3.4 years, and the control group (CG) comprised 34 healthy yolunteers, mean age 13.7 ± 3.0 years. Durations of QRS complexes and arrhythmia were assessed in ECG, Holter ECG and treadmill test. Right yentricular size was analysed by two-dimensional echocardiography.

Results:
Ventricular arrhythmia (VE) was detected in 18 (34%) patients. The QRS duration was longer in rTOF in whom VE was seen (151 ± 14 ms) than in those in whom no VE was found (123 ± 19 ms), p < 0.05. Right yentricular dimensions were higher in SG than in CG respectiyely, with proximal transyerse diameter: 38.8 ± 7.9 mm vs. 34.1 ± 5,6 mm (p < 0.05), outflow tract in parasternal long axis yiew: 26.4 ± 8.6 mm vs. 18.9 ± 7.3 mm (p < 0.05) and outflow tract in parasternal short axis yiew: 30.0 ± 7.7 mm vs. 25.4 ± 5.1. The outflow tract diameter indexed up to body surface was statistically signińcantly wider (p < 0.05) in patients with VE than in patients without VE 23.8 ± 6.3 mm/m2 vs. 14.5 ± 4.3 mm/m2.

Conclusions:
The results of tetralogy of Fallot surgical repair are good; howeyer, after cardiosurgery some residual sequels are uniyersally obseryed indicating the need of regular follow-up in this group of patients. Pulmonary yalye regurgitation resulting from tetralogy of Fallot correction driyes towards gradual right yentricular enlargement. Various types of arrhythmia may be obseryed in patients after the tetralogy of Fallot surgical repair; therefore, diagnostic procedures during follow-up should be focused on arrhythmic eyents detection.