Emergency pulmonary autograft mitral valve replacement in a child.

Mitral valve replacement in small children imposes significant clinical difficulties because of the relatively small mechanical prosthetic valves required and the need for lifelong anticoagulation therapy. A child weighing 10.4 kg presented with thrombosis of her 19-mm mechanical mitral prosthesis 4 weeks after implantation despite appropriate oral anticoagulation therapy. An emergency mitral valve replacement with a pulmonary autograft was successfully performed with encouraging short-term results.