Sildenafil Exposure and Hemodynamic Effect After Fontan Surgery

9 children post Fontan single-ventricle surgical palliation undergoing elective cardiac catheterization, median age 5.2 years, 55% boys, 67% systemic right ventricle.

Single-dose IV sildenafil (0.25, 0.35, or 0.45 mg/kg over 20 min).

Baseline measurements before sildenafil administration.

Peak sildenafil and desmethyl sildenafil concentration, and change in hemodynamic variables measured by cardiac catheterization and echocardiography immediately after administration.surrogate