Background Reconstructive surgery is the primary goal in pediatric patients with valve disease.However,in cases with irreparable valve lesions,valve replacement is the only option.This study aimed to retrospectively analyze the clinical experience of heart valve prosthesis replacement in children.Methods Between January 1990 and July 2009,35 pediatric patients (16 boys,19 girls) underwent mechanical valve replacement in Shandong University Qilu Hospital.The ages ranged from 2.5 to 14 years (mean,(8.8±3.8) years) and body weight varied from 11 to 37 kg (mean,(22.1±5.2) kg).Mechanical valve replacement was performed because of congenital heart disease in 23 patients,rheumatic disease in ten patients and infective endocarditis in two patients.St.Jude bileaflet mechanical valves were implanted in all the 35 patients including mitral valve replacement (MVR) in 18,aortic valve replacement (AVR) in 12,tricuspid valve replacement (TVR) in two,AVR and MVR in two and MVR and TVR in one.The size of the prostheses ranged between 19 and 27 mm.All patients received long-term anticoagulation treatment with sodium warfarin,aiming to maintain an international normalized ratio between 1.5 to 2.0.Follow-up was performed in all the patients with a total follow-up of 119.4 patient-years.Results The operative mortality was 8.57% (3/35).One patient,who underwent cardiac debridement and AVR,died 2 hours after being admitted to the intensive care unit because of severe low cardiac output syndrome and ventricular fibrillation.Two patients died of cardiogenic shock and renal failure during initial hospitalization after the operation.One patient who received replacement of a tricuspid valve developed complete heart block requiring temporary pacing and recovered sinus rhythm 4 days later.Thirty-two patients survived and their cardiac function was in New York Heart Association (NYHA) class Ⅰ to class Ⅱ when discharged.Late events included hemorrhage and endocarditis.Two patients required reoperation.No late deaths occurred during the follow-up.Conclusions Mechanical valve replacement remains an acceptable treatment option in children when the valve reparation is impossible or unsuccessful.The operative mortality and incidence of any valve-related events such as endocarditis,reoperation,thromboembolism or anticoagulation-related bleeding are acceptable.