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The following is a summary of “Correlation and consistency analysis between various indirect portal pressure gradients and actual portal pressure gradient,” published in the April 2025 issue of the BMC Gastroenterology by Chen et al.

Accurate assessment of portal hypertension is essential for guiding therapeutic strategies, including transjugular intrahepatic portosystemic shunt (TIPS) placement. The hepatic venous pressure gradient (HVPG), typically calculated as the difference between wedged hepatic venous pressure (WHVP) and free hepatic venous pressure (FHVP), is widely used to estimate portal pressure. However, discrepancies in venous pressure measurements may affect the accuracy of HVPG. This study aimed to compare the correlation and agreement between two HVPG calculation methods—F-HVPG (WHVP minus FHVP) and I-HVPG (WHVP minus inferior vena cava pressure [IVCP] in the hepatic segment)—with the portal pressure gradient (PPG), which is derived from the difference between portal venous pressure (PVP) and IVCP.

A retrospective analysis was conducted on 112 patients diagnosed with portal hypertension who underwent TIPS, along with intraoperative measurement of hemodynamic parameters, including FHVP, IVCP, WHVP, and PVP. F-HVPG and I-HVPG were calculated accordingly. Pearson’s correlation coefficients and coefficients of determination (R²) were computed to evaluate linear associations between parameters. Agreement between methods was assessed using Bland–Altman analysis, with a particular focus on patients exhibiting a pressure difference (FHVP – IVCP) greater than 2 mmHg.

In the full cohort, the correlation coefficients (r) between FHVP and IVCP, WHVP and PVP, F-HVPG and I-HVPG, F-HVPG and PPG, and I-HVPG and PPG were 0.835, 0.717, 0.946, 0.667, and 0.698, respectively (all p < 0.001). Corresponding R² values were 0.697, 0.514, 0.895, 0.445, and 0.487. Bland–Altman analysis indicated that F-HVPG and I-HVPG demonstrated the narrowest 95% limits of agreement. Among the subset of patients with FHVP–IVCP > 2 mmHg, I-HVPG demonstrated stronger correlation with PPG (r = 0.807, R² = 0.651) compared to F-HVPG (r = 0.648, R² = 0.420), and Bland–Altman plots showed better agreement between I-HVPG and PPG in this group.

Both F-HVPG and I-HVPG show high correlation and consistency in estimating portal pressure. However, I-HVPG appears to correlate more closely with directly measured PPG, particularly in patients with significant discrepancies between FHVP and IVCP. These findings suggest that I-HVPG may serve as a more accurate alternative for assessing portal pressure, especially when FHVP overestimates systemic venous pressure. Importantly, clinicians should be cautious in using HVPG alone to exclude patients from TIPS, given its tendency to underestimate true portal pressure.

Source: bmcgastroenterol.biomedcentral.com/articles/10.1186/s12876-025-03816-z