Approaches to the Diagnosis of Portal Hypertension: Non-Invasive or Invasive Tests?

Abstract: Portal hypertension is the main driver of complications in patients with advanced chronic liver disease (ACLD) and is defined by values of hepatic venous pressure gradient measurement (HVPG) > 5 mmHg. Values of HVPG ≥ 10 mmHg determine the presence of clinically significant portal hypertension (CSPH), the main predictor of the risk of variceal bleeding, hepatic decompensation, and mortality. However, its measurement is invasive and requires high expertise, so its routine use outside third level centers or clinical trials is limited. In the last decades, several non-invasive tests (NITs) have been developed and validated for the diagnosis of portal hypertension. Among these, liver (LSM) and spleen stiffness measurement (SSM) are the most promising tools available, as they have been proven accurate to predict CSPH, high-risk esophageal varices, decompensation, and mortality in patients with ACLD. In the last Baveno VI Consensus proceedings, LSM evaluation was recommended for the first time for diagnosis of CSPH (LSM > 20-25 kPa) and the screening of patients with a low probability of having high-risk varices (LSM < 20 kPa and platelet count > 150.000/mm 3 ). In this review, we aimed to summarize the growing evidence supporting the use of non-invasive tests for the evaluation of portal hypertension in patients with chronic liver disease. Keywords: liver stiffness, spleen stiffness, portal hypertension, hepatic venous pressure gradient, liver cirrhosis