Balloon-occluded Retrograde Transvenous Obliteration (BRTO): Preprocedural Evaluation and Imaging

Abstract

Patients undergoing balloon retrograde transvenous obliteration (BRTO) are mostly decompensated cirrhotic with either bleeding gastric varices (GV) or hepatic encephalopathy. It is crucial that clinicians are up-to-date with the assessments needed prior to BRTO to anticipate and prevent complications, and to deliver critical quality care. These patients will require preprocedural assessments and management, including endoscopic, clinical, laboratory, and imaging evaluation. Endoscopic evaluation is mandatory prior to BRTO, and it is highly recommended that it be performed at the same institution where BRTO will be performed. It is essential that clinicians are aware of the potential benefits and complications that may result from BRTO. These complications should be anticipated and prevented when possible. For GV bleeders, there should be consideration of a transvenous intrahepatic portosystemic shunt (TIPS) during or before BRTO in patients with refractory ascites or pleural effusion, as well as endoscopic banding or a TIPS in patients with high-risk esophageal varices. Patients undergoing BRTO are usually complicated and require a team approach. In this article, the authors address these assessment and preparatory management and planning procedures prior to the BRTO procedure as well as expected outcomes and potential complications.

Keywords: BRTO; Gastric varices; TIPS; liver cirrhosis; portal hypertension; splenorenal shunt.

Figure 1

Anatomy of the portal circulation: Gastric varices due to splenic vein thrombosis tend to arise from the short gastric veins running from the hilum of the spleen to the greater curvature aspect of the stomach rather than through splenorenal (asterisk) or gastrorenal shunts common with portal hypertensive fundal varices. IVC, inferior vena cava; PV, portal vein; LGV,left gastric vein; SMV, superior mesenteric vein; SV, splenic vein; SGV, short gastric vein; LRV, left renal vein. (Courtesy of Dr. Saher Sabri.)

Figure 2

Schematic diagram of Sarin's Endoscopic Classification of Gastric Varices: Fundal varices are included in two of the groups: (A) Type 1 gastroesophageal varices (GOV 1) are typically continuation of esophageal varices into the lesser curvature varices. (B) Type 2 gastroesophageal varices (GOV 2) when the esophageal and fundal varices are present in continuity over the cardia, (C) Type 1 isolated gastric varices (IGV 1), that are usually fundal gastric varices. (D) Type 2 isolated gastric varices (IGV 2) are gastric varices at ectopic sites in the stomach outside the cardiofundal region or the first part of the duodenum. An alternative classification based on vascular anatomy (determined by dominant feeder veins) has been proposed and is especially useful in consideration of balloon retrograde transvenous obliteration.

Figure 3

Preprocedural imaging with contrast-enhanced computed tomography (CECT).(A) Oblique coronal CECT shows patency of the main portal vein (small arrow). The posterior gastric vein (arrowhead) is the main feeding “afferent” vein for the gastric varices (large arrow). (B) Oblique coronal CECT shows gastric fundal varices (arrow) and gastrorenal shunt (arrowheads). (C) Axial CECT shows gastric fundal varices (arrow).

Figure 4

Preprocedural magnetic resonance imaging (MRI). (A) Contrast-enhanced MRI (CEMRI) in the coronal plane showing patency of the portal vein and the left gastric vein (arrowheads) as the main feeding “afferent” vein. (B) CEMRI in the coronal plane showing the posterior gastric vein (arrowheads) as the main feeding “afferent” vein. The gastrorenal shunt is also noted (arrow). CEMRI in the coronal (C) and axial (D) planes showing the gastrorenal shunt (arrowheads) and the opacified gastric fundal varices (arrow). (E) Axial T2-weighted MR image showing the gastric fundal varices as flow voids (arrow).