Ebstein's anomaly is an uncommon lesion of the tricuspid valve characterized by downward displacement of the tricuspid valve. The aim of the study was an analysis of the form, clinical outcome and treatment results in patients (pts) diagnosed with Ebstein anomaly. METHODS 28 pts were analysed. Material has been divided into 3 groups, depending on clinical symptoms. The group A was formed with mild shape of the defect, group B all pts presenting significant clinical symptoms requiring treatment, and group C made of pts having severe symptoms requiring intensive treatment including surgical intervention. RESULTS Anomaly had been detected in 13 boys and in 15 girls. Group A consisted of 6 children, including one boy diagnosed with defect prenatally. Described patient currently is followed-up in pulmonology outpatient clinic due to asthma. Other children are doing well and require no treatment. Group B was represented by 8 children requiring treatment of: sepsis, arrhythmia due to WPW syndrome and in one case ASD 2. Group C consisted of 14 patients. In 7 pts Ebstein anomaly was part of a complex congenital heart defect. In 5 cases dominating symptoms were severe heart failure with cyanosis and arrhythmia and in two cases sepsis. 10 pts had been treated surgically (7 pts had Blalock-Taussig shunt, 1 pt artificial valve replacement, 1 pt Fontan op. and 1 pt ASD 2 suture) where 8 died. The causes of death were: right ventricle failure and arrhythmia in 4, sepsis in 2, and pulmonary artery hypoplasia and metabolic acidosis also in 2 cases. CONCLUSIONS Ebstein anomaly includes wide spectrum of anatomical and clinical findings. The most severe forms require surgical intervention, however it can be a high risk procedure.