In the present study, we found that serum CA 125 levels were weakly correlated with functional status (6MWD, WHO-FC, and NT-proBNP) and echocardiographic (LVED, RVED, and pericardial effusion) and haemodynamic (SvO2, mRAP, and CI) parameters of PH after adjustment. The gene discussed is NPPB; the disease is pericardial effusion.