Significance of echocardiographic metrics including TRV and TAPSE/SPAP in mild haemodynamic pulmonary hypertension - data from EVIDENCE-PAH UK.

Abstract

Background: The 2022 ESC/ERS guidelines redefined pulmonary hypertension (PH) as a mean pulmonary artery pressure (mPAP) >20 mmHg on right heart catheterisation (RHC). Echocardiography, using metrics such as tricuspid regurgitation velocity (TRV), tricuspid annular plane systolic excursion (TAPSE), and TAPSE/systolic pulmonary artery pressure (TAPSE/SPAP), guides referral for RHC. However, the few studies evaluating echocardiographic performance using the ESC/ERS 2022 thresholds have combined the newly included population as a relatively modest subgroup within their overall analysis.

Results: We present a sample of 1,991 individuals from the EVIDENCE-PAH UK database. Our data demonstrate higher TRV and sPAP values and lower TAPSE/SPAP values with higher haemodynamic category. ROC analysis demonstrates that TRV, SPAP and TAPSE/SPAP perform well as predictors of mPAP > 20 mmHg and ≥25 mmHg (AUCs 0.785-0.830), but less well at predictive mPAP 21-24 mmHg (AUCs 0.656-0.686). In all PH patients and the mild PH (21-24 mmHg) subgroup, TAPSE/SPAP < 0.31 mm/mmHg predicted reduced survival (HR 2.01-3.14, p < 0.001). Similarly, in haemodynamically mild PH, TRV > 3.4 m/s was associated with worse survival compared to TRV < 2.5 m/s or 2.5-2.8 m/s (p < 0.001).

Conclusions: While established echocardiographic metrics (TRV, TAPSE/SPAP) are strong predictors of significant PH (mPAP ≥25 mmHg), they are less accurate for mild PH (mPAP 21-24 mmHg). Importantly, mild PH itself is associated with increased mortality, and within this group, TRV >3.4 m/s and TAPSE/SPAP <0.31 mm/mmHg identify patients at highest risk, supporting their prognostic utility even in early haemodynamic disease.