Congenital Cardiac Lesions Involving Systolic Flow Abnormalities Are Associated With Platelet Dysfunction in Children

Background Shear stress-induced platelet dysfunction (PD) is prevalent among adults with aortic stenosis. Our aim was to determine whether abnormal platelet function was associated with specific congenital cardiac lesions in children. Methods The charts of 407 children who had undergone cardiopulmonary bypass and had preoperative platelet function analysis were evaluated. Patients were assigned to 1 of 11 different lesion categories. Platelet dysfunction (PD) was defined as prolonged closure time (CT) as measured with a platelet function analyzer. Odds ratio (OR) estimates for prolonged CT were calculated for each lesion category. Mean CTs were compared with Tukey-Kramer separated means testing. Analysis of variance modeling was used to determine association between hematocrit value and CT. Results CT in patients with ventricular septal defects (VSD) and right ventricular outflow tract obstruction (RVOTO) lesions was prolonged. OR analysis found that patients with VSDs (OR, 2.46) or RVOTO (OR, 2.88) had at least a 95% probability of an abnormal CT. In contrast, patients with atrial septal defect (ASD), bidirectional Glenn procedure (BDG), and pulmonary insufficiency (PI) had a reduced probability of a prolonged CT ( p p Conclusions PD was common in children with congenital cardiac lesions involving systolic flow abnormalities and was uncommon among children with lesions having diastolic abnormalities. Lower preoperative hematocrit values were associated with prolonged CTs, suggesting subclinical bleeding secondary to excessive platelet shearing.