Balloon-occluded retrograde transvenous obliteration

Balloon-occluded retrograde transvenous obliteration (BRTO) is a technique used by interventional radiologists in the treatment of gastric varices, particularly those with prominent infra-diaphragmatic portosystemic venous shunts (e.g. gastro-renal and gastro-caval shunts).

The technique is more popular in Asia, where it is a first-line treatment for gastric variceal hemorrhage . Nonetheless, modified BRTO techniques are gaining popularity in Western countries, particularly in the setting of failed endoscopic intervention and in patients with a contraindication for TIPS .

Indications

  • gastric varices
    • active hemorrhage, after failed endoscopic treatment
    • contraindications for TIPS (e.g. high MELD scorehepatic encephalopathy)
    • prophylaxis against re-bleeding in the setting of primary endoscopic therapy

Procedure

The classic BRTO procedure has been largely supplanted by modified techniques which involve shorter procedure times. These include:

  • vascular plug-assisted retrograde transvenous obliteration (PARTO)
  • coil-assisted retrograde transvenous obliteration (CARTO)
  • balloon-occluded antegrade transvenous obliteration (BATO)

The techniques employed are typically adapted depending on specific portosystemic anatomy and operator experience and preference.

Preprocedural evaluation
  • standard laboratory studies, including liver enzymes and coagulation panel
  • CT imaging - ideally immediately preceding BRTO intervention. To define:
    • afferent & efferent gastric variceal anatomy
    • splenic & portal vein patency
Technique

The classic BRTO procedure is as follows:

  • systemic venous access obtained via femoral vein approach, alternatively via internal jugular vein approach
  • a 6 to 12-French vascular sheath placed
  • the target shunt (typically gastro-renal shunt via left renal vein) catheterized using with selective catheter (e.g. Simmons or Cobra selective catheter)
  • occlusive balloon is inflated to occlude the shunt, then contrast injected upstream of the occlusion (retrograde venography) to further evaluate variceal anatomy and identify major collateral vessels
  • significant efferent collateral vessels are embolized using coils, and/or gelfoam and sclerosant
  • sclerosant is injected upstream of the balloon into the gastric varices themselves, with the occlusive balloon remaining in place for 4-20 hours until abdominal radiograph shows stasis of sclerosant
  • Modified techniques such as PARTO, CARTO, and BATO essentially follow the same procedure, except that shunt occlusion is permanently achieved by vascular plugging or coiling. This significantly reduces procedure time and decreases the risk of balloon rupture.

    Complications

    • common
      • typically transient and self-limited
        • epigastric/back pain
        • fever
        • hematuria
        • nausea
      • worsening of esophageal varices
      • temporary worsening of ascites or hydrothorax
    • altered respiratory function (presumably secondary to altered pulmonary perfusion)
    • portal or renal vein thrombosis - usually asymptomatic
    • bacterial peritonitis

    Outcomes

    • high rate of technical success (range 77-100%)
    • re-bleeding rates up to 15%, although more commonly reported ~5%

    See also