The accuracy and influencing factors of Doppler echocardiography in estimating pulmonary artery systolic pressure: comparison with right heart catheterization: a retrospective cross-sectional study.

Background: Noninvasive assessment of pulmonary artery systolic pressure by Doppler echocardiography (sPAP) has been widely adopted to screen for pulmonary hypertension (PH), but there is still a high proportion of overestimation or underestimation of sPAP. We therefore aimed to explore the accuracy and influencing factors of sPAP with right heart catheterization (RHC) as a reference.

Methods: A total of 218 highly suspected PH patients who underwent RHC and echocardiography within 7 days were included. The correlation and consistency between tricuspid regurgitation (TR)-related methods and RHC results were tested by Pearson and Bland-Altman methods. TR-related methods included peak velocity of TR (TR Vmax), TR pressure gradient (TR-PG), TR mean pressure gradient (TR-mPG), estimated mean pulmonary artery pressure (mPAP), and sPAP. With mPAP ≥ 25 mm Hg measured by RHC as the standard diagnostic criterion of PH, the ROC curve was used to compare the diagnostic efficacy of sPAP with other TR-derived parameters. The ratio (sPAP-sPAP)/sPAP was calculated and divided into three groups as follows: patients with an estimation error between - 10% and + 10% were defined as the accurate group; patients with an estimated difference greater than + 10% were classified as the overestimated group; and patients with an estimation error greater than - 10% were classified as the underestimated group. The influencing factors of sPAP were analyzed by ordinal regression analysis.

Results: sPAP had the highest correlation coefficient (r = 0.781, P < 0.001), best diagnostic efficiency (AUC = 0.98), and lowest bias (mean bias = 0.07 mm Hg; 95% limits of agreement, - 32.08 to + 32.22 mm Hg) compared with other TR-related methods. Ordinal regression analysis showed that TR signal quality, sPAP level, and pulmonary artery wedge pressure (PAWP) affected the accuracy of sPAP (P < 0.05). Relative to the good signal quality, the OR values of medium and poor signal quality were 0.26 (95% CI: 0.14, 0.48) and 0.23 (95% CI: 0.07, 0.73), respectively. Compared with high sPAP level, the OR values of low and medium sPAP levels were 21.56 (95% CI: 9.57, 48.55) and 5.13 (95% CI: 2.55, 10.32), respectively. The OR value of PAWP was 0.94 (95% CI: 0.89, 0.99). TR severity and right ventricular systolic function had no significant effect on the accuracy of sPAP.

Conclusions: In this study, we found that all TR-related methods, including sPAP, had comparable and good efficiency in PH screening. To make the assessment of sPAP more accurate, attention should be paid to TR signal quality, sPAP level, and PAWP.