Repair of ventricular septal defect and aortic regurgitation associated with severe hemophilia B.

A child with severe factor IX deficiency who underwent an open-heart operation using extracorporeal circulation is described. The factor IX level was normalized immediately before operation and at the end of cardiopulmonary bypass by infusing prothrombin complex concentrate and fresh frozen plasma. Partial thromboplastin time and factor IX serum levels were monitored for 20 days postoperatively and showed factor IX activity higher than 50%.