Pre- and post-operative studies of fibrinolysis and prothrombin in cyanotic congenital heart disease.

Multiple components of the fibrinolytic mechanism (plasminogen, plasmin, antiplasmin, fibrinogen, fibrin degradation products) and factor II (prothrombin) levels were studied in 40 children with cyanotic congenital heart disease (CCHD) prior to corrective surgery. Seven of these were also studied post-operatively. A further 17 children were studied after corrective surgery only. Pre-operatively, increased fibrinolysis could bedemonstrated in only 7.5-12% of patients, and there was no correlation between the levels of fibrinolytic components and the severity of polycythemia or post-operative blood loss. There was no evidence of fibrinolysis post-operatively. Pre-operatively, low prothrombin levels were common (25%), were correlated with the amount of post-operative bloodloss and were restored to normal by corrective surgery. Hypoprothrombinaemia is one of the most significant haematological abnormalities in CCHD.