IL6 and pulmonary artery-aorta diameter ratio measurement: Among the participants in group 3, those with uncomplicated PAA had median (IQR) serum IL-6 values of 17.2 pg/mL (8.5–36.8), and those with complicated PAA had 60.25 pg/mL (27.1–169) serum IL-6 (P < 0.001).