Procoagulant and anticoagulant factor levels were significantly lower in patients after the Fontan operation independent of hemodynamic variables peculiar to the Fontan circulation. Increased factor VIII level requires further evaluation as a cause of thrombosis in patients with Fontan physiology and may also indicate a subset of these patients in whom anticoagulation is indicated.

This longitudinal study in patients with identical cardiac disease and staged surgical procedures confirms the increase in factor VIII level after the Fontan procedure. This is an acquired defect, and although the cause remains to be determined, monitoring factor VIII levels after the Fontan operation could indicate a subset of patients at risk for thrombosis.

No abstract