Abstract 128

The Anticardiolipin antibodies (aCL) are autoantibodies that are associated with thrombophilia. These aCL antibodies may bind to endothelial cells and interfere with its normal function in maintaining homeostasis between the procoagulant and fibrinolytic pathways. Cyanosis in congenital heart disease is associated with a hypercoagulable state. In acyanotic congenital heart disease with shunts the pulmonary vascular endothelium is subjected to shear forces. The endothelium plays a critical role in the regulation of thrombosis and when it is activated by shear stress, it has the potential to secrete prothrombotic substances. We evaluated patients with underlying congenital heart disease for the presence of these antibodies. In the normal population the prevalence of aCL is < 2%. METHODS: Consecutive patients who consented formed our study groups. Sera was collected from 16 patients ages 4 years ±4.9 (mean ±SD) with acyanotic congenital heart disease prior to surgery (14/16 had significant shunts to require surgery),) and 8 patients ages 13.2 years ±7.3 with cyanotic congenital heart disease. Sera were also collected from 30 healthy patients, aged 5.8 years ±3.6 who served as the control population. The IgG, IgM and IgA aCL were measured by ELISA (Sigma, St. Louis, Mo., USA) in all patients. Normal for adults are IgM ≤ 5 U, IgG ≤ 14 U, and IgA≤ 15 U. None of the patients had history of thromboembolism or recent infections. No patient had an acquired valvular heart disease. RESULTS: Only one patient from the healthy control groups was positive for aCL per adult values. All others were negative. CONCLUSION: The prevalence of anticardiolipin antibodies in children with underlying congenital heart disease is probably same as the normal population. It may be of interest to follow these children for development of aCL as they grow older.