Background: Endothelial activation and vascular inflammation are thought to be the mechanisms of pulmonary hypertension. Increased expression of the intercellular adhesion molecule (ICAM-1) and raised serum level of its soluble form (sICAM-1) are found in various conditions associated with endothelial activation.
Methods: Serum samples from 31 children (14 boys and 17 girls; age, 4.9 +/- 4.6 years) with congenital heart disease (CHD) collected at the time of cardiac catheterization were analyzed for sICAM-1 level. Uni- and multivariable stepwise linear regression analyses were performed for the following variables against the sICAM-1 level: age, hemoglobin, serum creatinine, systemic arterial pressure (SAP), pulmonary arterial pressure (PAP), pulmonary blood flow (Qp) and resistance (Rp), systemic blood flow (Qs) and resistance (Rs), Qp/Qs, Rp/Rs, and pulmonary and systemic oxygen saturation.
Results: The sICAM-1 levels in children who had CHD with and without pulmonary hypertension were 411 +/- 110 and 344 +/- 81 ng/ml, respectively (p = 0.11). In the univariable models, age, serum creatinine, systolic PAP, mean PAP, diastolic PAP, Rp, and Rp/Rs were significantly correlated with sICAM-1 level. In the multiple stepwise regression model, only mean PAP remained as an independent predictor of sICAM-1 level (r = 0.55; p = 0.002).
Conclusion: Children with CHD and pulmonary hypertension had a trend toward elevated sICAM-1 compared with CHD children who had no pulmonary hypertension. A linear correlation was found between mean pulmonary arterial pressure and sICAM-1 level.