2D shear wave liver elastography by Aixplorer to detect portal hypertension in cirrhosis: An individual patient data meta-analysis

Abstract

Background & aims: Liver stiffness measured with 2-dimensional shear wave elastography by Supersonic Imagine (2DSWE-SSI) is well-established for fibrosis diagnostics, but non-conclusive for portal hypertension.

Methods: We performed an individual patient data meta-analysis of 2DSWE-SSI to identify clinically significant portal hypertension (CSPH), severe portal hypertension and large varices in cirrhosis patients, using hepatic venous pressure gradient and upper endoscopy as reference. We used meta-analytical integration of diagnostic accuracies with optimized rule-out (sensitivity-90%) and rule-in (specificity-90%) cut-offs.

Results: Five studies from seven centres shared data on 519 patients. After exclusion, we included 328 patients. Eighty-nine (27%) were compensated and 286 (87%) had CSPH. 2DSWE-SSI < 14 kPa ruled out CSPH with a summary AUROC (sROC), sensitivity and specificity of 0.88, 91% and 37%, and correctly classified 85% of patients, with minimal between-study heterogeneity. The false negative rate was 60%, of which decompensated patients accounted for 78%. 2DSWE-SSI ≥ 32 kPa ruled in CSPH with sROC, sensitivity, specificity and correct classifications of 0.83, 47%, 89% and 55%. In a subgroup analysis, the 14 kPa cut-off showed consistent sensitivity and higher specificity for patients with compensated cirrhosis, without ascites, viral aetiology or BMI < 25 kg/m² . 2DSWE-SSI ruled out severe portal hypertension and large varices with fewer correctly classified and lower sROC, and with minimal benefit for ruling in.

Conclusion: Liver stiffness using 2-dimensional shear wave elastography below 14 kPa may be used to rule out clinically significant portal hypertension in cirrhosis patients, but this would need validation in populations of compensated liver disease. 2DSWE-SSI cannot predict varices needing treatment.

Keywords: Aixplorer; Decompensated liver disease; compensated advanced chronic liver disease; liver vein catheterization; supersonic shear imagine.