Proximal Splenic Artery Embolization (PSAE) for the Treatment of Refractory Ascites in Decompensated Cirrhosis

Refractory ascites is a common complication of decompensated cirrhosis and carries a substantial symptom burden and reduced quality of life. Standard management includes repeated large-volume paracentesis and, for eligible candidates, placement of TIPS. TIPS is effective for many patients but carries a meaningful risk of hepatic decompensation, new or worsening hepatic encephalopathy and is not a safe option for patients with a high Model for End-Stage Liver Disease (MELD) score, prior encephalopathy, cardiac dysfunction, or unfavorable vascular anatomy.

PSAE is a catheter-based procedure in which coils and/or vascular plugs are placed in the proximal splenic artery to reduce arterial blood flow to the spleen while preserving splenic viability through collateral vessels. By lowering splenic blood flow into the portal venous system, PSAE is expected to reduce portal pressure and the driving force behind ascites formation, without creating a new vascular connection that could trigger hepatic encephalopathy.

This is a prospective, multi-center, single-arm, open-label study. Eligible participants undergo a single PSAE procedure, with Hepatic Venous Pressure Gradient (HVPG) measurement performed immediately before and after embolization, followed by 6 months of structured follow-up including laboratory testing, imaging, and patient-reported assessments. An independent Data Safety Monitoring Board (DSMB) reviews safety data at pre-specified intervals throughout the study.

The co-primary effectiveness endpoints are the change from baseline to Month 6 in the average monthly number of large-volume paracentesis sessions and the change in the average monthly volume of ascitic fluid drained. The primary safety endpoint is the proportion of participants who experience a major procedure-related adverse event within 6 months of PSAE.

Secondary endpoints include change in HVPG, hepatic artery resistive index by Doppler ultrasound, diuretic dose, and time to resolution of paracentesis dependence. Additional assessments capture patient-reported symptom burden and quality of life, physical frailty, hepatic encephalopathy grading, laboratory measures of liver and kidney function, and body composition by CT.

Inclusion criteria

• Age ≥ 18 years at the time of informed consent.
• Decompensated cirrhosis confirmed by clinical, laboratory, radiographic, or histologic criteria.
• Portal hypertension of sinusoidal origin. Pre-sinusoidal (e.g., idiopathic non-cirrhotic portal hypertension, schistosomiasis) and post-sinusoidal (e.g., Budd-Chiari syndrome, right-heart failure, constrictive pericarditis) etiologies are excluded.
• Refractory or recurrent ascites defined as ascites not controlled by maximum tolerated diuretic therapy (spironolactone ≤ 400 mg/day + furosemide ≤ 160 mg/day, or maximum tolerated doses below these limits) and sodium restriction, or diuretic-intractable due to diuretic-induced complications.
• Demonstrated large-volume paracentesis (LVP) dependence for ≥ 3 consecutive months prior to screening, with ≥ 2 LVP sessions per month on average during that window, documented in the institutional medical record or in external paracentesis procedure records released to the investigator.
• Ineligible or relatively contraindicated for TIPS. Acceptable reasons include but are not limited to: MELD-Na > 18 with additional risk factors, pre-existing or recurrent overt hepatic encephalopathy, advanced age with comorbidity, clinically significant cardiopulmonary disease, or anatomic contraindication.
• Life expectancy ≥ 6 months in the judgment of the enrolling investigator.
• Able and willing to provide written informed consent and to adhere to the study visit and assessment schedule.
• Abdominal cross-sectional imaging (CT or MRI) within 60 days of enrollment confirming patency of the main portal vein and main splenic vein, and absence of findings that would contraindicate PSAE.

Exclusion criteria

• Age < 18 years.
• Unable to provide informed consent and without an appropriate legally authorized representative.
• Pre-sinusoidal or post-sinusoidal portal hypertension (e.g., extrahepatic portal vein thrombosis, idiopathic non-cirrhotic portal hypertension, schistosomiasis, Budd-Chiari syndrome, hepatic sinusoidal obstruction syndrome, constrictive pericarditis, right-heart failure).
• Main portal vein thrombosis, splenic vein thrombosis, or superior mesenteric vein thrombosis on screening imaging.
• Active listing for liver transplantation with MELD-Na ≥ 20 at screening, or any listing status in which transplantation within 6 months is judged highly likely by the site transplant team. (Listed participants with MELD-Na < 20 and low anticipated short-term transplant probability may be enrolled with documented site transplant-team concurrence.)
• Pre-existing splenectomy, prior distal splenic artery embolization, or pre-existing splenic abscess, large splenic infarction (≥ 30% of splenic parenchyma), or splenic mass on imaging.
• Active or uncontrolled systemic infection, including spontaneous bacterial peritonitis in the prior 14 days, bacteremia in the prior 14 days, or any infection requiring parenteral antibiotics at the time of screening.
• Active gastrointestinal bleeding within 14 days, or untreated high-risk esophageal or gastric varices (primary prophylaxis not yet established) - treatable prior to enrollment.
• Severe coagulopathy not correctable to INR ≤ 2.0 and platelets ≥ 30 × 10⁹/L on the day of the procedure.
• Known severe allergy to iodinated contrast not manageable with standard pre-medication, or contrast contraindication precluding cross-sectional CT imaging.
• eGFR < 30 mL/min/1.73 m² not on renal replacement therapy, unless iodinated contrast use can be minimized per site protocol and nephrology concurrence is documented.
• Pregnancy or breastfeeding. Participants of childbearing potential must have a negative serum pregnancy test at screening and agree to effective contraception through Month 6.
• Hepatocellular carcinoma beyond BCLC Stage A, or any active extrahepatic malignancy with life expectancy < 6 months.
• Active substance use disorder other than alcohol or tobacco that, in the investigator's judgment, would preclude protocol adherence. Active alcohol use disorder is not exclusionary but is captured (AUDIT-C) and analyzed as a pre-specified covariate.
• Enrollment in another interventional clinical trial within 30 days or concurrent with this study that could confound endpoints, including TIPS-related trials.
• Any medical, psychiatric, or social condition that in the investigator's judgment would preclude safe participation or adherence to the protocol.