Congenital heart disease in children does not affect ADP-dependent platelet aggregation before cardiac surgery

Background Previous research has indicated that congenital heart defects may cause an impaired coagulation capacity in children. Identifying this effect before surgery could enable clinicians to take steps to prevent postoperative coagulopathy. Objectives 1) Compare the preoperative platelet aggregation response in children with congenital heart defects with that of a control group of healthy children using multiple electrode aggregation and vasodilator stimulated phosphoprotein, and 2) measure the effect of cardiac surgery on platelet aggregation in the congenital heart defects group using the same analyses. Methods Thirty-six children with congenital heart defects were enrolled in this prospective, observational study. Platelet aggregation was measured before surgery, at the end of cardiopulmonary bypass, and on the first postoperative day using multiple electrode aggregation and vasodilator stimulated phosphoprotein. Multiple electrode aggregation and vasodilator stimulated phosphoprotein were also analyzed in a control group of healthy children. Results There were no differences in the preoperative multiple electrode aggregation or vasodilator stimulated phosphoprotein results between the groups. Platelet aggregation as measured with multiple electrode aggregation decreased significantly from preoperative levels to the end of CPB, with ADP-induced aggregation dropping from 68 U (SD 21 U) to 31 U (SD 26 U), p < 0.01. On the first postoperative day, aggregation had returned to preoperative levels or increased. Vasodilator stimulated phosphoprotein results decreased steadily, from a preoperative mean of 87 % (SD 4 %) to 82 % (SD 7 %) at the end of CPB, and 78 % (SD 11 %) on the first postoperative day. Conclusion Platelet aggregation does not differ between children with congenital heart defects and healthy children when analyzed with multiple electrode aggregation or vasodilator stimulated phosphoprotein. The multiple electrode aggregation values returned to normal on the first day after surgery, while vasodilator stimulated phosphoprotein values continued to decrease.