Patients with advanced chronic liver diseases treated at the Vienna General Hospital of the Medical University of Vienna will be offered to participate in this prospective observational trial - including an optional participation in a biobank.

Clinical parameters and laboratory parameters will be recorded for all patients and patients will undergo a regular follow-up schedule with clinical visits at the Vienna General Hospital.

This study is linked to a biobank with serum/plasma, ascitic fluid, urine, GI tract mucosal biopsies, liver biopsies and stool collected from the study participants.

Patients with advanced chronic liver disease (ACLD) as evident by HVPG>5mmHg or liver biopsy showing F3/F4 fibrosis or as suggested by liver stiffness measurement (LSM) ≥10kPa can be included in the VICIS study. Most patients will be recruited on the day of HVPG measurement performed for screening of clinically significant portal hypertension (CSPH) or on the day of upper GI endoscopy for screening for the presence of varices. Next to the detailed characterization of patients by epidemiologic, clinical and laboratory parameters, the degree of portal hypertension will be assessed by HVPG, liver (LSM) and spleen (SSM) stiffness will be assessed by transient elastography, the presence of ascites, splenomegaly, portosystemic collaterals, PVT and liver lesions will be assessed by ultrasound and optionally cross-sectional imaging.

In addition, patients will be asked to (optionally) participate in biobank sampling including serum/plasma, ascitic fluid, urine, GI tract mucosal biopsies, stool, liver biopsies and stool. All patients recruited in the VICIS study will be prospectively followed every 3 months (decompenated ACLD) or every 6 months (compensated ACLD) patients with clinical visits at the Cirrhosis Outpatient Clinic at the Vienna General Hospital. These assessments include a detailed assessment of risk factors (such as a structured interview of alcohol consumption), the recording of decompensating events (such as ascites, hepatic encephalopathy, variceal bleeding), screening for PVT and HCC, recording of medications and other clinically-relevant information.

Inclusion Criteria:

• Age >18 years and <100 years
• Diagnosis of advanced chronic liver disease (by liver stiffness ≥10kPa, HVPG>5mmHg or Histology F3/F4)
• Written informed consent

Exclusion Criteria:

• Withdrawal of written informed consent

Patient with advanced chronic liver disease diagnosed and/or treated at the Medical University of Vienna will be screened for inclusion/exclusion criteria.