Alfapump® System in the Treatment of Refractory or Recurrent Ascites (POSEIDON Study)

Inclusion Criteria: At the time of Initial Screening: 1. Patients \> 18 years of age 2. Cirrhosis of the liver defined by histological and/or clinical, endoscopic, laboratory and radiological criteria. 3. Refractory or recurrent ascites primarily managed with periodic therapeutic paracentesis . Patients must have a minimum of 2 therapeutic paracenteses in the 30 Days prior to enrollment 4. Not a candidate for (e.g. refused, contraindicated) Transjugular intrahepatic portosystemic shunt (TIPS) or previously implanted TIPS is permanently obstructed or non-functioning. 5. Screened for esophageal varices and on optimal management 6. Absence of contraindications to prophylactic antibiotic use from time of pump implant 7. Life expectancy of at least 6 months following pump implant (approximately 10 months from enrollment) 8. Capable of giving written informed consent, willing to comply with study procedures including the 3-month pre-implant observation period and ability to operate and charge the device. 9. Women of childbearing age should use adequate contraceptives. Reassessed at time of implant procedure (Pivotal Cohort Only): 10. Has required a minimum of 5 therapeutic paracenteses in the 3-month observation period prior to pump implant Exclusion Criteria: At the time of Initial Screening: 1. Renal failure defined as serum creatinine higher than 1.5 mg/dL 2. More than one episode of spontaneous bacterial peritonitis over the previous 6 months 3. More than one episode of bacterascites over the previous 6 months 4. Recurrent urinary infections as per standard criteria, defined as 2 or more episodes over the last 6 months 5. Evidence of loculated ascites, as per imaging 6. Hepatocellular carcinoma, exceeding Milan criteria or for which RF ablation is anticipated 7. Pregnant females or females anticipating pregnancy during study period 8. Patients currently enrolled in another interventional clinical study that has not reached the primary endpoint assessment point, or (for pivotal cohort) patients who have previously had an alfapump implanted 9. Immuno-modulatory treatment (including azathioprine, methotrexate, anti-TNF therapies) used within last 4 months (corticosteroids at stable dose over the last 4 months but \< 15 mg/day, or in tapering doses are allowed) 10. Known or suspected hepatic or extra hepatic malignancy (other than skin cancer and in-situ cancers), unless adequately treated or in complete remission for ≥ 3 years 11. History of bladder cancer 12. BMI\>40 presenting a risk for technical difficulties for surgery or catheter implantation 13. Contraindications to general anesthesia 14. Comorbid condition or other reason (example hypertension) that may preclude stopping diuretics after enrollment 15. MELD-Na Score \> 20 16. Budd Chiari syndrome (Pivotal cohort only) 17. Clostridium difficile infection within the past year Assessed or re-assessed at time of pump implant: 18. Acute gastrointestinal hemorrhage requiring transfusions over the previous 42 days 19. Condition that prevents continued cessation of diuretic use 20. Patient condition does not allow the implant procedure to be performed within the limits of acceptable risk (e.g. cardiovascular comorbidities, variceal bleeding within the previous 6 weeks, skin infections or skin ulcers of the anterior abdominal wall within 2 weeks of device placement) 21. Hepatocellular carcinoma exceeding Milan criteria or for which RF ablation is anticipated 22. ICU admission since enrollment in the 30 days preceding pump implant procedure 23. INR \>/= 2.0 24. Platelet count of \< 50,000 /μL at the time of implantation, unless the platelet count is ≥30,000 / μL and bleeding risk can be satisfactorily addressed with means such as platelet infusion during the implant procedure and/or thrombopoietin receptor agonists 25. Bacterial peritonitis within 4 weeks of implant procedure (this includes peritonitis diagnosed at the time of intervention) 26. Bacterascites within 4 weeks of implant procedure (this includes bacterascites diagnosed at the time of intervention). Note: at the time of final eligibility (just prior to implantation) the subject will not be allowed to move forward with the procedure if he/she has experienced an episode bacterascites within four weeks of the implant procedure date. 27. Serum sodium \<125 mmol/L 28. Urinary infection within the last 2 weeks 29. Obstructive uropathy, residual urinary volume exceeding 100 ml, or any bladder anomaly which might contraindicate implantation of the device 30. Evidence of renal failure, defined as serum creatinine higher than or equal to 1.5 mg/dL, in the preceding 30 days 31. Evidence of loculated ascites, as per imaging 32. Pregnant females or females anticipating pregnancy during study period