A modified 4-strata risk assessment incorporating TAPSE/sPAP for pulmonary arterial hypertension: evidence from a large chinese real-world cohort
S Li, Z Huang, Q Zhao, L Deng, Q Zeng, Y Wu, Z Zhao, Y Ran, Z Liu, Q LuoAbstract
Background
Pulmonary arterial hypertension (PAH) is a progressive disease with poor prognosis. The 2022 ESC/ERS guidelines recommend the 4-strata risk model based on WHO functional class (WHO-FC), N-terminal pro-brain natriuretic peptide (NT-proBNP) and 6-minute walk distance (6MWD) to assess one-year mortality risk and guide treatment decisions at follow-up. However, in routine practice in China, 6MWD is frequently unavailable. The tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (TAPSE/sPAP) ratio, an echocardiographic marker of right ventricular–pulmonary artery coupling with established prognostic value is routinely assessed in PH centers and may offer a practical alternative for follow-up risk assessment.
Purpose
To develop and internally validate a modified 4-strata risk assessment model incorporating TASPE/sPAP as a practical alternative to 6MWD for follow-up risk stratification in PAH.
Methods
This single-center retrospective cohort study included treatment-naïve, newly diagnosed PAH patients who underwent right heart catheterization and had follow-up assessment with either 6MWD or echocardiography at a cardiovascular disease specialized hospital between 1 January 2018 and 30 November 2024. The cohort was randomly divided into training and test sets (70%:30%). WHO-FC and NT-proBNP were scored according to 2022 ESC/ERS 4-strata risk tool. Intermediate-low- and intermediate-high-risk TAPSE/sPAP cut-offs were derived from multivariable Cox regression optimized for 1-, 2-, and 3-year mortality, while low- and high-risk thresholds followed ESC guidelines. Model discrimination was assessed using the C-index and time-dependent AUC. Changes in risk strata from baseline to first follow-up were also evaluated.
Results
Among 12,858 screened patients, 769 were eligible and 542 with TAPSE/sPAP follow-up were analyzed (mean age 36.1 ± 11.8 years; 78.8% female). A modified 4-strata model integrating WHO FC, NT-proBNP, and TAPSE/sPAP was developed. The model showed good discrimination, with C-indices of 0.79 (training) and 0.72 (test). Two- and three-year AUCs were 0.82 and 0.83 in the training set, and 0.74 and 0.73 in the test set. The optimal TAPSE/sPAP cut-off was 0.26, and thresholds defining 4-strata were 0.19, 0.26, and 0.32. An univariable TAPSE/sPAP model remained robust (C-index 0.71). Five-year survival rates were 97.4%, 87.4%, 67.6%, and 27.8% from low to high risk (P<0.001). The model further discriminated prognosis within intermediate-risk patients, particularly for long-term outcome. Risk distribution shifted from 22.0%, 40.6%, 26.2%, and 11.2% at baseline to 40.8%, 35.8%, 17.0%, and 6.4% at follow-up.
Conclusion
A modified 4-strata model incorporating TAPSE/sPAP provides good discrimination for follow-up risk stratification in a real-world Chinese PAH cohort and may serve as a practical alternative when 6MWD is unavailable.Survival Analysis by Risk GroupFor image description, please refer to the figure legend and surrounding text.Sankey Diagram of Risk StratificationFor image description, please refer to the figure legend and surrounding text.