This study will be used to train an algorithm using Methacetin breath test (MBT) measures and to select a cut-off to determine presence or absence of Clinically Significant Portal Hypertension (CSPH) as defined by Hepatic Venous Gradient Pressure (HVPG) ≥ 10mmHg,

The portal pressure leaving the liver is measured by using a balloon catheter before and after a wedge. The difference of the pressure between the wedge and the free is the hepatic venous pressure gradient. Methacetin breath test is hypothesized to also identify CSPH and the agreement to the reference standard (HVPG) will be assessed in this study.

Inclusion Criteria:

• Adult men or women (>18 years of age)
• Known chronic liver disease with cirrhosis
• Europe: Indicated to undergo HVPG testing
• US: Consented for HVPG
• For patients treated with beta blockers: They have to be on a stable dose for at least 6 weeks prior to any study related tasks
• For patients who stopped their treatment with beta blockers: Their last dose should be at least 6 weeks prior to any study related tasks

Exclusion Criteria:

• Decompensated cirrhosis as clinically defined by the presence of ascites, hepatic encephalopathy, variceal bleeding or hepatorenal syndrome
• Renal failure (creatinine > 2.5 mg/dl)
• Known acute renal tubular disease Known hypotension (Systolic Pressure <100mmHg)
• Hypocoagulablity defined as PT >6 and INR >2.3.
• Congestive heart failure (assessed clinically as NIHA >2)
• Known pulmonary hypertension (right ventricular systolic pressure > 45 mm Hg)
• Uncontrolled diabetes mellitus (HBA1C >9.5gr%)
• Concurrent prednisone or immunosuppressive treatment, if therapy and/or response to treatment are not stable for at least 3 months.
• Documented or suspected hepatocellular carcinoma
• Gastric bypass surgery or extensive small bowel resection
• Total parenteral nutrition
• Any organ transplant recipient
• Pregnant or breast feeding
• Allergy to acetaminophen and/or other related medications
• Documented drug-related concurrent hepatotoxicity or drug-related silent steatosis or drug-related fibrosis (e.g. amiodarone, methotrexate and tamoxifen)
• Uncontrolled malabsorption or diarrhea
• Documented non-cirrhotic PHT, partial / complete portal venous occlusion, hepatic venous occlusion, previous PHT surgery, or placement of a transjugular intrahepatic portosystemic shunt (TIPS)
• Primary or secondary biliary cirrhosis, primary or secondary sclerosing cholangitis, hepatic sarcoidosis, or other cholestatic disorders
• Subjects unable to perform the MBT within 7 days of HVPG procedure.
• Subject should not have taken any of the following for at least 48 hours prior to the breath test: Acyclovir , allopurinol, amiodarone, carbamazepine, cimetidine, ciprofloxacin, daidzein, (herbal) disulfiram, echinacea, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, montelukast, norfloxacin, phenylpropanolamine, phenytoin, propafenone, rifampin, terbinafine, ticlopidine, thiabendazole, verapamil, zileuton or oral contraceptives or any medication that might interfere with Methacetin metabolism or might affect CYP 1A2
• Subject should not have taken amiodarone or statins within the last 30 days prior to the breath test or HVPG procedure

The Methacetin used in the breath test has a high extraction rate and is removed after less than 48 hours. Follow up was done for 48 hours after breath test. After 30 days another follow up phone call was made.