Association Between Biomarkers and Kidney Function Decline in Pulmonary Hypertension

Inclusion Criteria: * Inpatients aged ≥18 years * Undergoing right heart catheterization (RHC) Exclusion Criteria: * multifactorial or indeterminate PH, for which no single underlying mechanism could be reliably classified * active tumor disease requiring targeted therapy * inflammatory or autoimmune disease with renal involvement requiring systemic immunosuppressive treatment * unexplained kidney function decline, defined as serum creatinine increase ≥0.5 mg/dL from baseline within the prior 7 days before RHC * Chronic kidney disease with eGFR \<20 ml/min/1.73 m2 * non-kidney failure requiring extracorporeal or peritoneal ultrafiltration for diuretic-resistant volume overload * if they had received non-steroidal anti-inflammatory drugs or intravenous contrast within 72 hours before RHC * prediagnosed glomerulonephritis * polycystic kidney disease * postrenal obstruction * single kidney (functional or anatomical) * solid organ transplantation * anticipated life expectancy of \<12 months * likelihood of receiving advanced therapy (mechanical circulatory assist device/lung or cardiac transplant) * pregnancy or possibility of pregnancy in the next 12 months * inability to cooperate with respiratory maneuvers during renal Doppler * refusal to participate * not available for follow-up visits