Published online Aug 15, 2020. doi: 10.4251/wjgo.v12.i8.931
Peer-review started: January 16, 2020
First decision: April 18, 2020
Revised: May 8, 2020
Accepted: July 1, 2020
Article in press: July 1, 2020
Published online: August 15, 2020
Processing time: 208 Days and 18.4 Hours
Portal pressure accurately predicts the risk of peri-operative morbidity and mortality in liver carcinoma. The limitations of HVPG measurement are that it is invasive and impractical for routine clinical practice. Thus, non-invasive measurement methods are urgently needed.
Doppler sonography offers real-time observation of blood flow with qualitative and quantitative assessments, and the application of microbubble-based contrast agents has improved the detectability of peripheral blood flow. The aim of this study was to clarify whether simple, non-invasive US parameters correlate with the invasive transjugular PPG measurement and to develop a formula to estimate PPG.
To investigate whether ultrasonography (US)-based portal pressure assessment could replace invasive transjugular measurement.
A cohort of 102 patients with HCC was selected (mean age: 54 ± 13 years, male/female: 65/37). Pre-operative US parameters were assessed by two independent investigators, and multivariate logistic analysis and linear regression analysis were conducted to develop a predictive formula for the portal pressure gradient (PPG). The estimated PPG predictors were compared with the transjugular PPG measurements. Validation was conducted on another cohort of 20 non-surgical patients.
The mean PPG was 17.32 ± 1.97 mmHg. Univariate analysis identified the association of the following four parameters with PPG: Spleen volume, portal vein diameter, portal vein velocity (PVV), and portal blood flow (PBF). Multiple linear regression analysis was performed, and the predictive formula using the PVV and PBF was as follows: PPG score = 19.336-0.312 x PVV (cm/s) + 0.001x PBF (mL/min). The PPG score was confirmed to have good accuracy with an area under the curve (AUC) of 0.75 (0.68-0.81) in training patients. The formula was also accurate in the validation patients with an AUC of 0.820 (0.53–0.83).
The formula based on ultrasonographic Doppler flow parameters shows a significant correlation with invasive PPG and, if further confirmed by prospective validation, may replace the invasive transjugular assessment.
The formula for the prediction of PPG should be verified on a larger and external validation cohort for widespread acceptance.