CST3 and kidney disorder: We aimed to investigate Fontan-Associated Renal Disease (FARD) through comprehensive phenotyping using biomarkers of renal function and injury, as well as ultrasound assessment of intrarenal hemodynamics.<h4>Methods</h4>We prospectively collected data on serum creatinine and cystatin C levels, and 24-h urine creatinine clearance and albumin excretion in 25 Fontan patients, comparing them to healthy age- and sex-matched controls.