Reappraisal of the reliability of Doppler echocardiographic estimations for mean pulmonary artery pressure in patients with pulmonary hypertension: a study from a tertiary centre comparing four formulae

Different Doppler echocardiography (DE) models have been proposed for estimation of mean pulmonary arterial pressures (PAMP) from tricuspid regurgitation (TR) jet velocity. We aimed to compare four TR-derived DE models in predicting the PAMP measured by right heart catheterization (RHC) in different groups of precapillary pulmonary hypertension (PH). A total of 287 patients with hemodynamically pre-capillary PH were enrolled (mean age = 51 ± 17.4 years, 59.9% female). All patients underwent DE before RHC (< 3 h) and four formulae (F) were used for TR-derived PAMP estimation (PAMP-DE). These were as follows: F1 = Chemla (0.61 × systolic pulmonary artery pressure [PASP] + 2); F2 = Friedberg (0.69 × PASP - 0.22), F3 = Aduen (0.70 × PASP); and F4 = Bech-Hanssen (0.65 × PASP - 1.2). The PASP and PAMP (mmHg) measured by RHC were 89.1 ± 30.4 and 55.8 ± 20.8, respectively. In the overall PH group, DE estimates for PASP (r = 0.59, P = 0.001) and PAMP (r = 0.56, P = 0.001 for all) showed significant correlations with corresponding RHC measures. Concordance was noted between Chemla and Bech-Hanssen, and Aduen and Bech-Hanssen. The Bland-Altman plot showed that Chemla and Bech-Hanssen overestimated and Friedberg and Aduen underestimated PAMP-RHC measures. Paired-t test showed significant systematic biases for Aduen and Bech-Hanssen while Passing-Bablok non-parametric analysis revealed significant systematic biases all four PAMP-DE estimates. There was poor agreement between PAMP-RHC measures and PAMP-DE deciles (Kappa values were 0.112, 0.097, 0.095, and 0.121, respectively). This study showed a poor agreement between PAMP-DE estimates by four TR-derived formulae and PAMP-RHC in patients with PH, regardless of the etiology. However, these results can not be fully extrapolated to a normal population and did not address the reliability of DE estimates for PH screening procedures.