Background: Patients who require extracorporeal membrane oxygenation (ECMO) postsurgery for congenital heart disease (CHD) frequently experience severe bleeding episodes. Whereas recombinant-activated factor VII (rFVIIa) has proven efficacy in counteracting intractable hemorrhage in various scenarios, its use in patients on ECMO is limited by the increased risk for thrombotic events. Methods: Between December 2004 and January 2006, ECMO was used in 10 pediatric patients following cardiac surgery, of whom seven were treated with rFVIIa because of intractable hemorrhage. Their medical records were reviewed with respect to variations in chest tube output and transfusion requirements, occlusion of or thrombus formation in the ECMO circuit and the occurrence of thromboembolic events. Outcome and rate of ECMO circuit occlusion were compared with historic controls. Results: Three patients died, and four survived (none of the deaths was attributable to thrombus formation or bleeding). All patients were treated with aprotinin prior to and during rFVIIa therapy. Two patients developed an occlusion of the oxygenator, one after receiving co-medication with a FXIII concentrate, another after RBC transfusion in the ECMO system. In two patients, thrombus formation was observed in the ECMO system on inspection after discontinuation. Thromboembolic events were not observed. Conclusions: Recombinant-activated factor VII in a median dosage of 90 μg·kg -1 was used in seven pediatric patients on ECMO. Rates of ECMO system occlusions and mortality did not differ from historic controls. Neither the reduction of chest tube output nor the blood product transfusion requirements did reach statistical significance.