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The concept of obliterating varices that complicate portal hypertension dates back to the 1970s, but its minimally invasive clinical utilization was probably lost with the advent of the transjugular intrahepatic portosystemic shunt (TIPS). The conception of retrograde obliteration of a gastrorenal shunt via the left renal vein was reported by Olson et al from the University of Indiana. However, the definition, development, technical perfection, and clinical implementation of the balloon-occluded retrograde transvenous obliteration (BRTO) occurred in Japan (by Kanagawa et al and others). The BRTO-procedure is currently undergoing a renaissance in the United States particularly for patients who are not TIPS candidates.

Variceal bleeding is one of the major complications of portal hypertension. Gastric variceal (GV) bleeding is less common than esophageal variceal (EV) bleeding, however, is associated with a high morbidity and mortality. Balloon-occluded retrograde transvenous obliteration (BRTO) is an established procedure for the management of gastric varices in Japan and has shown promising results in the past decade. The technical success rate, intent-to-treat (including technically failed BRTO-procedures) obliteration rate, and the obliteration rate of gastric varices of technically successful BRTO procedures was 91% (79–100%), 86% (73–100%), and 94% (75–100), respectively. BRTO is successful in controlling active gastric variceal bleeding in 95% of cases (91–100%) and in significantly reducing or resolving encephalopathy in 100% of cases. However, BRTO diverts blood into the portal circulation and increases the portal hypertension, thus aggravating esophageal varices with their potential for bleeding. The 1-, 2-, and 3-year esophageal variceal aggravation rates are 27–35%, 45–66%, and 45–91%, respectively. The gastric variceal rebleed rate of successful BRTO procedures, the intent-to-treat gastric variceal rebleed rate, and the global (all types of varices) variceal rebleed rate are 3.2–8.7%, 10–20%, and 19–31%, respectively. However, the advantage of diverting blood into the portal circulation and potentially toward the liver is improved hepatic function and possible patient survival. Unfortunately, the improved hepatic function is transient (for 6–12 months); however, it is preserved in the long-term (1–3 years). Patient 1-, 2-, 3-, and 5-year survival rates are 83–98%, 76–79%, 66–85%, and 39–69%, respectively. Patient survival is determined by baseline hepatic reserve and the presence of hepatocellular carcinoma.

Alternative routes for transvenous obliteration are often sought in the management of gastric varices, as well as in the management of other nongastric varices (ectopic varices) such as duodenal and mesenteric varices. These alternative routes can be classified into A-portal venous access routes and B-systemic venous access routes. Anecdotally, alternative routes are more commonly required with duodenal and mesenteric varices compared with gastric varices. Twelve percent (2-19%) of patients with gastric varices require alternative/adjunctive variceal access routes. The most common alternative route described for transvenous obliteration of gastric varices is the percutaneous transhepatic route, which is commonly referred to in the Japanese literature as percutaneous transhepatic obliteration (PTO). The percutaneous transhepatic obliteration route can be performed alone or in combination with the more traditional balloon-occluded retrograde transvenous obliteration (BRTO) transrenal route. Percutaneous transhepatic obliteration by itself is successful in 44-100% of cases for obliterating gastric varices and is rarely unsuccessful when it is combined with BRTO. Other alternative routes are less commonly described and as a result, their clinical outcomes are relatively anecdotal. However, they are technically more challenging and are less commonly successful. These routes include, but are not confined to transphrenic, transileocolic, trans-TIPS (transvenous intrahepatic portosystemic shunt), transgonadal, transazygous, and transrenal capsular vein approaches.