BACKGROUND: Congenital heart disease (CHD) is a risk factor for infective endocarditis (IE). We aimed to assess the impact of cardiac interventions on the frequency and microbial profile of IE in children with CHD. METHODS: Episodes of IE were analyzed in children aged < or =18 years with CHD between 1995 and 2005 with respect to cardiac surgery or catheter interventions with or without implantation of foreign material. RESULTS: Diagnosis of IE was made in 14 (0.36%) of 3826 children with CHD including native IE in 6 and postinterventional IE in 8 patients. During the period 3029 cardiac interventions (1944 surgeries; 1085 catheters) were performed; foreign material was implanted in 1360 interventions (1139 surgeries; 221 catheters) including all 8 patients with postinterventional IE. Cardiac intervention by itself did not change the risk for IE compared with no intervention. The risk of IE after implantation of foreign material was higher than following intervention without implantation (odds ratio, 21.0; 95% confidence interval, 1.2-365; P < 0.05). Pacemaker implantation was associated with the highest risk for IE (odds ratio, 11.0; 95% confidence interval, 2.6-46.5; P < 0.001). Staphylococci were the most frequently isolated organisms in foreign material-associated IE. CONCLUSIONS: Cardiac intervention in children with CHD does not increase the risk for IE. Postinterventional IE in children with CHD is strongly linked to implantation of foreign material, especially of pacemaker.