Intermediate-term results after the aortic valve replacement using bileaflet mechanical prosthetic valve in children

Objective: Intermediate/long-term results after aortic valve replacement using bileaflet mechanical valve in children should be clarified as a standard of treatment of aortic valve disease in children. Methods: Forty-five patients aged under 15 years underwent 46 aortic valve replacements using bileaflet mechanical prosthetic valve. Patients' ages ranged from 1 to 15 years (9 years as a median value), and follow-up period was 9.2 years as a median value (maximum 19 years). Results: In situ valve replacement was performed in 21 procedures, while annular enlargement was required in 25 procedures (Nicks 10, Yamaguchi 3, Manouguian 2, Konno 10). All patients except two received prosthesis 19 mm or larger in size. There was one operative death and two late deaths. Two episodes of cerebral infarction, two valve thrombosis, two re-operations, one infective endocarditis, and one sudden death were recognized as valve-related complications in five patients. The reasons for re-operation were prosthesis-patient mismatch in one (Ross procedure) and valve thrombosis in one (re-replacement). At 15 years after the operation, re-replacement free rate, valve-related event free rate and actuarial survival rate were 94 ± 4%, 86 ± 6% and 92 ± 4%, respectively. The transprosthetic flow velocity estimated by Doppler echocardiography at the final follow-up was well correlated with manufactured valve area index (cm²/body surface area). Conclusions: Although aortic annular enlargement was required in more than half of the cases, intermediate-term results after aortic valve replacement using bileaflet mechanical prosthetic valve in children was satisfactory. Indications for alternative treatment such as Ross procedure might be considered in limited cases.