Tricuspid Annular Plane Systolic Excursion/Systolic Pulmonary Artery Pressure Ratio and Cardiorenal Syndrome Type 2 in the Systemic Sclerosis EUSTAR Cohort

Objective: The aim of the study was to evaluate the association between the tricuspid annular plane systolic excursion (TAPSE)/systolic pulmonary artery pressure (sPAP) ratio and estimated glomerular filtration rate (eGFR) and their association with mortality in the European Scleroderma Trials and Research (EUSTAR) cohort. Methods: Patients with systemic sclerosis (SSc) from the EUSTAR database with TAPSE, sPAP, and parameters required to calculate eGFR were included. Logistic regression and Cox regression analysis were performed to evaluate TAPSE/sPAP as a risk factor for chronic kidney disease (CKD) and overall survival. Results: A total of 2,370 patients with SSc were included; 284 (12%) patients had CKD stage 3a–5. TAPSE/sPAP (odds ratio [OR] 0.479; 95% CI 0.310–0.743; P < 0.001), arterial hypertension (OR 3.118; 95% CI 2.173–4.475; P < 0.001), diastolic dysfunction (OR 1.670; 95% CI 1.148–2.428; P < 0.01), and N-terminal pro-B-type natriuretic peptide (OR 1.165; 95% CI 1.041–1.304; P < 0.01) were associated with CKD stage 3a–5. TAPSE/sPAP ≤0.32 mm/mm Hg (hazard ratio [HR] 3.589; 95% CI 2.236–5.761; P < 0.001), eGFR <60 mL/min per 1.73 m² (HR 2.818; 95% CI 1.777–4.468; P < 0.001), and age (HR 1.782; 95% CI 1.348–2.356; P < 0.001) were the most significant predictive factors for all-cause mortality. A total of 276 patients with SSc had pulmonary hypertension (PH) confirmed by right heart catheterization, with 69 (25%) having CKD stage 3a–5. No difference was found in eGFR between patients with PH with reduced or normal cardiac index. Conclusion: Reduced TAPSE/sPAP ratio is independently associated with CKD. TAPSE/sPAP ratio ≤0.32 mm/mm Hg and eGFR <60 mL/min per 1.73 m² are prognostic factors for all-cause mortality. In patients with SSc with PH, eGFR is independent by reduced cardiac output.