Predictive value of echocardiographic parameters for screening pulmonary hypertension in the revised ESC/ERS guidelines

Background The current guideline recommends a peak tricuspid regurgitation velocity (TRV) ≥2.8 m/s on echocardiography for pulmonary hypertension (PH) screening; however, the threshold was based on the previous PH definition (mean pulmonary arterial pressure [mPAP] ≥25 mmHg). Therefore, It remains unclear whether this cut-off value is still appropriate under the revised PH definition (mPAP >20 mmHg). Purpose To evaluate the optimal cut-off value of peak TRV and whether an additional echocardiographic parameter using inferior vena cava diameter can improve the predictive performance in screening PH with mPAP >20 mmHg. Methods We retrospectively analyzed patients who underwent both right heart catheterization and echocardiography at our institute between January 2018 and December 2023. Peak TRV and inferior vena cava diameter were measured within five days before and after right heart catheterization. We categorized estimated right atrial pressure (eRAP) into four levels: 3 (0-5), 8 (5-10), 13 (10-15), and 18 (15-20) mmHg using an inferior vena cava diameter (cut-off 17 mm) and respiratory variation (50 %). We quantified the risk of PH with mPAP >20 mmHg by echocardiographic parameters using logistic regression models. The discrimination of peak TRV and eRAP for screening PH was assessed by receiver operating characteristic curve analysis, using the Youden Index for the optimal cut-off value. We further assessed the predictive performance of the cross-categorization of peak TRV and eRAP for the risk of PH. Result In a total of 598 individuals, 248 patients (41%) were diagnosed as PH with mPAP >20 mmHg. The median mPAP was 19 mmHg (IQR: 15–25), and the median pulmonary vascular resistance was 2.0 Wood Units (IQR: 1.3–3.3). Peak TRV was significantly associated with the risk of PH (per 0.1 m/s, odds ratio 14.2 and 95% CI [8.6-23.5]). The c-statistic for peak TRV in detecting PH was 0.79 (95% CI: 0.75–0.83). At an optimal cut-off value of 2.7 m/s, peak TRV demonstrated moderate sensitivity 0.66 and high specificity 0.84 for detecting PH. Adding eRAP to peak TRV significantly improved diagnostic performance with the c-statistic of 0.81 (95% CI: 0.78–0.85) and net reclassification improvement of 0.15 (p = 0.009) (Figure 1). Furthermore, eRAP ≥10 mmHg was associated with a higher PH risk and those with both elevated peak TRV and eRAP showed the strongest association with PH risk (Figure 2A). We developed a PH risk score using eRAP ≥10 mmHg (1 point) and peak TRV ≥2.7 m/s (2 points), showing a linear association with the risk for PH (Figure 2B). Conclusion In the revised PH definition (mPAP >20 mmHg), a peak TRV of 2.7 m/s was suggested as the optimal cut-off value for PH screening. Although peak TRV alone showed limited performance in the prediction of PH, the addition of eRAP to peak TRV may be promising for the assessment of PH by simple echocardiographic measurements.