Pre– and Post–Balloon-Occluded Retrograde Transvenous Obliteration Clinical Evaluation, Management, and Imaging: Indications, Management Protocols, and Follow-up

Balloon-occluded retrograde transvenous obliteration for treatment of portal hypertensive related varices

PURPOSE OF REVIEW

Balloon-occluded retrograde transvenous obliteration (BRTO) is becoming a more commonly used procedure to manage various complications of liver disease. It is important to understand the technique of the procedure, the indications for its use, and also potential associated complications.

RECENT FINDINGS

BRTO is superior to endoscopic cyanoacrylate injection and transjugular intrahepatic portosystemic shunt for bleeding gastric varices associated with a portosystemic shunt and should be considered a first line therapy in these patients. In addition, it has been shown to be useful in controlling ectopic variceal bleeding, improving portosystemic encephalopathy, and also in modulating blood flow in the post liver transplant setting. Modified versions of BRTO, plug assisted retrograde transvenous obliteration and coil assisted retrograde transvenous obliteration, have been developed to reduce procedure time and improve complication rates.

SUMMARY

As the use of BRTO expands in clinical practice it will be important for gastroenterologists and hepatologists to better understand the procedure. There are still many research questions left to answer regarding the use of BRTO in specific situations and for specific patient populations.

Transvenous obliteration of gastric varices

Gastric varices on the background of portal hypertension occur less frequently than esophageal varices but they develop at lower portal pressure and are associated with more massive bleedings and higher mortality rate. Balloon-occluded retrograde transvenous obliteration (BRTO) has been well documented as an effective therapy for gastric varices caused by portal hypertension. However, BRTO requires long-term, higher-level post-procedural monitoring and can have complications related to balloon rupture and adverse effects of sclerosing agents. Several modified BRTO techniques have been developed, including vascular plug-assisted retrograde transvenous obliteration, coil-assisted retrograde transvenous obliteration, and balloon-occluded antegrade transvenous obliteration. This article provides an overview of BRTO various and modified BRTO techniques.

Hepatic venous pressure gradient after balloon-occluded retrograde transvenous obliteration and liver stiffness measurement predict the prognosis of patients with gastric varices

BACKGROUND

Balloon-occluded retrograde transvenous obliteration (BRTO) is a treatment option for patients with gastric varices (GVs). This study aimed to clarify the clinical significance of portal hypertension estimated by the hepatic venous pressure gradient (HVPG), subsequent exacerbation of esophageal varices (EVs), and prognosis of patients who underwent BRTO for GVs.

METHODS

Thirty-six patients with GVs treated with BRTO were enrolled in this study, and their HVPG was measured before (pre-HVPG) and on the day after BRTO (post-HVPG). After BRTO, patients were followed-up for a median interval of 24.5 (3-140) months. Clinical factors related to EVs exacerbation and prognosis after BRTO were retrospectively analyzed.

RESULTS

Post-HVPG increased compared to pre-HVPG in 21 out of 36 patients (58%), and post-HVPG was overall significantly higher compared to pre-HVPG (P = 0.009). During the observation period, 19 patients (53%) developed EVs exacerbation, and the cumulative EVs exacerbation rates at 1, 3 and 5 years after BRTO were 27%, 67%, and 73%, respectively. Pre-HVPG was not related to EVs exacerbation, although elevation of post-HVPG to ≥ 13 mmHg (P < 0.01) and high level of serum aspartate aminotransferase (P < 0.05) were significant independent risk factors for EVs exacerbation after BRTO. Fourteen patients (38.9%) died during the observation period. An elevated value of liver stiffness measurement (LSM) of ≥ 21 kPa was a significant independent risk factor for poor prognosis after BRTO (P < 0.05).

CONCLUSIONS

HVPG increases after BRTO. HVPG after BRTO has greater predictive ability for subsequent EVs exacerbation than HVPG before BRTO. LSM is a potential prognostic parameter in patients who undergo BRTO.

RK, K. MRP. Review of Applied Anatomy, Hemodynamics, and Endovascular Management of Ectopic Varices

Portal hypertension leads to the opening up of collateral pathways to bypass the occlusion or resistance in the portal system. Ectopic varices are formed by such collaterals at many various sites along the gastrointestinal tract other than the usual location, that is, gastroesophageal region. Early diagnosis of ectopic varices needs strong clinical suspicion and contrast-enhanced computed tomography scan as endoscopy may often fail to pinpoint a source. In contrast to gastric varices where the understanding of the disease, as well as endovascular management, is widely studied and documented, the same is not true for ectopic varices due to low incidence. Understanding the applied anatomy and hemodynamic classification is important to decide the most suitable therapy. Interventional radiological procedures are aimed at either decompressing the varices or obliterating them and depend on the patency of the portal system, underlying etiology, and local expertise.

AGA Clinical Practice Update on Management of Bleeding Gastric Varices: Expert Review

Management of bleeding gastric varices (GV) presents a unique challenge for patients with portal hypertension. Despite over thirty years of diagnostic and treatment advances standardized practices for bleeding GV are lacking and unsupported by adequate evidence. There are no definitive natural history studies to help with risk assessment or prospective clinical trials to guide clinical decision making. Available literature on the natural history and management of gastric varices consists of case series, restricted cohort studies, and a few small randomized trials, all of which have significant selection biases. This review summarizes the available data and recommendations based on expert opinion on how best to diagnose and manage bleeding from gastric varices. Table 1 summarizes our recommendations.

Management of portal hypertension severe complications

Portal hypertension is a clinical syndrome characterized by an increase in the portal pressure gradient, defined as the gradient between the portal vein at the site downstream of the site of obstruction and the inferior vena cava. The most frequent cause of portal hypertension is cirrhosis. In patients with cirrhosis, portal hypertension is the main driver of cirrhosis progression and development of hepatic decompensation (ascites, variceal hemorrhage and hepatic encephalopathy), which defines the transition from compensated to decompensated stage. In decompensated patients, treatments aim at lowering the risk of death by preventing further decompensation and/or development of acute-on-chronic liver failure. Decompensated patients often pose a complex challenge which typically requires a multidisciplinary approach. The aims of the present review were to discuss the current knowledge regarding interventional treatments for patients with portal hypertension complications as well as to highlight useful information to aid hepatologists in their clinical practice. Specifically, we discussed the indications and contraindications of transjugular intra-hepatic portosystemic shunt and for the treatment of gastro-esophageal variceal hemorrhage in patients with decompensated cirrhosis (first section); we reviewed the use of interventional treatments in patients with hepatic vein obstruction (Budd-Chiari Syndrome) and in those with portal vein thrombosis (second section); and we briefly comment on the most frequent applications of selective splenic embolization in patients with and without underlying cirrhosis (third section).

Management Options for Gastric Variceal Hemorrhage

Importance

Varices are one of the main clinical manifestations of cirrhosis and portal hypertension. Gastric varices are less common than esophageal varices but are often associated with poorer prognosis, mainly because of their higher propensity to bleed.

Observations

Currently, treatments used to control and manage gastric variceal bleeding include β-blockers, endoscopic injection sclerotherapy, endoscopic variceal ligation, endoscopic variceal obturation, shunt surgery, transjugular intrahepatic portosystemic shunts, balloon-occluded retrograde transvenous obliteration (BRTO), and modified BRTO. In the past few decades, Western (United States and Europe) interventional radiologists have preferred transjugular intrahepatic portosystemic shunts that aim to decompress the liver and reduce portal pressure. Conversely, Eastern radiologists (Japan and South Korea) have preferred BRTO that directly targets the gastric varices. Over the past 20 years, BRTO has evolved and procedure-related risks have decreased. Owing to its safety and efficiency in treating gastric varices, BRTO is now starting to gain popularity among Western interventional radiologists. In this review, we present a comprehensive literature review of current and emerging management options, including BRTO and modified BRTO, for the treatment of gastric varices in the setting of cirrhosis and portal hypertension.

Conclusions and Relevance

Balloon-occluded retrograde transvenous obliteration has emerged as a safe and effective alternative treatment option for gastric variceal hemorrhage. A proper training, evidence-based consensus and guideline, thorough preprocedural and postprocedural evaluation, and a multidisciplinary team approach with BRTO and modified BRTO are strongly recommended to ensure best patient care.

Coexistence of "extra-gastric afferent-efferent direct connection" with gastric varices: CT evaluation and clinical significance

PURPOSE

To evaluate the prevalence of extra-gastric direct connection between afferent and efferent veins of gastric varices (GVs) (i.e., EAEDC) and its clinical significance during balloon-occluded retrograde transvenous obliteration (BRTO).

MATERIALS AND METHODS

57 patients who underwent BRTO for GVs obliteration were retrospectively enrolled in this study. Pre-procedural CT images were reviewed for the presence of EAEDC. Patients were categorized into group A (patients with EAEDC) and group B (Patients with no detectable EAEDC). Intraprocedural images were reviewed to see if EAEDCs could be seen and if additional techniques were used to preserve or occlude them. Post-procedural CT images were reviewed for GVs obliteration, portal/splenic vein thrombosis, EAEDC patency, and ascites exacerbation. Post-procedural esophageal varices aggravation was evaluated by upper endoscopy.

RESULTS

39 EAEDCs were identified in CT images of 35 patients (i.e., group A = 61.4%). Among them, only 20 EAEDCs were visualized during BRTO. In the remaining 22 patients, EAEDC was not identified in CT images or during BRTO (i.e., group B = 38.6%). There was no statistically significant difference between group A and B regarding post-BRTO GVs obliteration and portal/splenic vein thrombosis. Use of additional techniques to preserve EAEDC patency had significantly reduced the incidence of ascites and esophageal varices exacerbation (p = 0.036 and 0.028, respectively). In patients with EAEDC diameter ≥ 5 mm, EAEDC preservation or obliteration by coils or balloon had significantly reduced the injected sclerosant volume (p = 0.003).

CONCLUSION

CT is very useful for EAEDC detection. EAEDC preservation may decrease the incidence of post-BRTO ascites and esophageal varices exacerbation.

Balloon occluded retrograde transvenous obliteration for bleeding gastric varices: Eyes see what the mind knows

Approximately one in six patients with portal hypertension who develop varices at sites of portosystemic venous collaterals has gastric varices due to hepatofugal flow into the gastric veins. Bleeding from gastric varices, though less common, has a higher mortality and morbidity compared to bleeding esophageal varices, which are easier to manage endoscopically. The efferent channel for gastric varices is mostly the gastrorenal shunt (GRS) which opens into the left renal vein. Balloon-occluded transvenous obliteration (BRTO) involves accessing the GRS with an aim to temporarily occlude its outflow using a balloon catheter and at the same time injecting sclerosant mixture within the varix so as to cause its thrombosis and thereby obliteration. BRTO is one of the mainstays of minimally invasive treatment for bleeding gastric varices. In the minority of cases where the GRS is absent, conventional BRTO is technically not possible. However, accessing the small alternate shunt from the inferior phrenic vein may be possible if one is aware of its existence.

A Comprehensive Review of Portosystemic Collaterals in Cirrhosis: Historical Aspects, Anatomy, and Classifications

Portosystemic collateral formation in cirrhosis plays an important part in events that define the natural history in affected patients. A detailed understanding of collateral anatomy and hemodynamics in cirrhotics is essential to envisage diagnosis, management, and outcomes of portal hypertension. In this review, we provide detailed insights into the historical, anatomical, and hemodynamic aspects to portal hypertension and collateral pathways in cirrhosis with emphasis on the various classification systems.

Balloon-occluded retrograde transvenous obliteration versus transjugular intrahepatic portosystemic shunt for treatment of gastric varices due to portal hypertension: A meta-analysis

BACKGROUND AND AIM

The aim of this study was to compare the feasibility and safety of both balloon-occluded retrograde transvenous obliteration (BRTO) versus transjugular intrahepatic portosystemic shunt (TIPS) for treatment of gastric varices due to portal hypertension through the method of meta-analysis.

METHODS

PubMed, Embase, and Cochrane Library were searched for both randomized controlled trials and cohort studies concerning BRTO compared with TIPS in the treatment of gastric varices from their inception to April 26, 2015. The Cochrane network RevMan 5.3 software was used for statistic analysis. The primary markers that need to be evaluated contained technical success rate, hemostasis rate, incidence rate of postoperative rebleeding, incidence rate of hepatic encephalopathy, and postoperative procedure-related complication. Study-specific odds ratios (ORs) were combined to calculate pooled value by using random effects model.

RESULTS

Five original studies were included in total. Meta-analysis showed that BRTO and TIPS had no difference in aspects of technical success rate (OR, 0.19; 95% confidence interval [CI], 0.03-1.08; P = 0.06), hemostasis rate (OR, 3.41; 95% CI, 0.33-35.40; P = 0.30), and incidence rate of postoperative procedure-related complication (OR, 1.98; 95% CI, 0.44-8.84; P = 0.37). However, BRTO had a lower incidence rate of post-operative rebleeding (OR, 0.27; 95% CI, 0.09-0.81; P = 0.02) and a lower incidence rate of postoperative encephalopathy (OR, 0.05; 95% CI, 0.02-0.13; P < 0.00001).

CONCLUSIONS

Balloon-occluded retrograde transvenous obliteration was a technically feasible as well as a secure method for the treatment of gastric varices originated from portal hypertension. It may have the potential to be an alterative shunt approach of TIPS, when suitable patients selected.

Endovascular management of gastric varices

Bleeding from gastric varices is a major complication of portal hypertension. Although less common than bleeding associated with esophageal varices, gastric variceal bleeding has a higher mortality. From an endovascular perspective,transjugular intrahepatic portosystemic shunts (TIPS) to decompress the portal circulation and/or balloon-occluded retrograde transvenous obliteration (BRTO) are utilized to address bleeding gastric varices. Until recently, there was a clear medical cultural divide between the strategy of decompressing the portal circulation (TIPS creation, for example) and transvenous obliteration for the management of gastric varices. However, the practice of BRTO is gaining acceptance in the United States and its practice is spreading rapidly. Recently, the American College of Radiology has identified BRTO to be a viable alternative to TIPS in particular anatomical and clinical scenarios. However, the anatomical and clinical applications of BRTO were not defined beyond the conservative approach of resorting to BRTO in non-TIPS candidates. The article discusses the outcomes of BRTO and TIPS for the management of gastric varices individually or in combination. Definitions, endovascular technical concepts and contemporary vascular classifications of gastric variceal systems are described in order to help grasp the complexity of the hemodynamic pathology and hopefully help define the pathology better for future reporting and lay the ground for more defined stratification of patients not only based on comorbidity and hepatic reserve but on anatomy and hemodynamic classifications.

Balloon-occluded retrograde transvenous obliteration for recurrent fundal gastric variceal bleeding in an adolescent

Gastric variceal bleeding is associated with high morbidity and mortality. Balloon-occluded retrograde transvenous obliteration is a relatively new treatment used to control bleeding gastric varices that involves transvenous sclerosis of gastric varices through a spontaneous gastrorenal shunt. Here, we report on a 14-yr-old patient that underwent balloon-occluded retrograde transvenous obliteration for refractory bleeding fundal varices in the setting of esophageal varices and cirrhosis, which did not respond to medical management or endoscopic injection. This case report serves as a reminder that balloon-occluded retrograde transvenous obliteration can successfully control fundal variceal bleeding in pediatric patients and may serve as a bridge to liver transplantation.

Portosystemic shunt syndrome and endovascular management of hepatic encephalopathy

The term "portosystemic shunt syndrome" was coined by Kumamoto et al referring to reduction of the hepatic reserve (reflected by progression of the Child-Pugh score) over 5 years compared with portal hypertensive cirrhotics without gastrorenal shunts or with prior history of obliterated gastrorenal shunts. Saad et al elaborated on this term further by describing a complete syndrome with clinical findings (including worsening liver failure and hepatic encephalopathy [HE]) and imaging findings (including hepatic atrophy, portal vein thrombosis, and paucity of intrahepatic portal vein radicles). This article discusses the syndrome in detail. In addition, the article describes the types of HE and the endovascular management of shunt-related HE.

Management of gastric varices

According to their location, gastric varices (GV) are classified as gastroesophageal varices and isolated gastric varices. This review will mainly focus on those GV located in the fundus of the stomach (isolated gastric varices 1 and gastroesophageal varices 2). The 1-year risk of GV bleeding has been reported to be around 10%-16%. Size of GV, presence of red signs, and the degree of liver dysfunction are independent predictors of bleeding. Limited data suggest that tissue adhesives, mainly cyanoacrylate (CA), may be effective and better than propranolol in preventing bleeding from GV. General management of acute GV bleeding must be similar to that of esophageal variceal bleeding, including prophylactic antibiotics, a careful replacement of volemia, and early administration of vasoactive drugs. Small sample-sized randomized controlled trials have shown that tissue adhesives are the therapy of choice for acute GV bleeding. In treatment failures, transjugular intrahepatic portosystemic shunt (TIPS) is considered the treatment of choice. After initial hemostasis, repeated sessions with CA injections along with nonselective beta-blockers are recommended as secondary prophylaxis; whether CA is superior to TIPS in this scenario is not completely clear. Balloon-occluded retrograde transvenous obliteration (BRTO) has been introduced as a new method to treat GV. BRTO is also effective and has the potential benefit of increasing portal hepatic blood flow and therefore may be an alternative for patients who may not tolerate TIPS. However, BRTO obliterates spontaneous portosystemic shunts, potentially aggravating portal hypertension and its related complications. The role of BRTO in the management of acute GV bleeding is promising but merits further evaluation.

Thrombocytopenia in Patients with Gastric Varices and the Effect of Balloon-occluded Retrograde Transvenous Obliteration on the Platelet Count

OBJECTIVES

Gastric varices primarily occur in cirrhotic patients with portal hypertension and splenomegaly and thus are probably associated with thrombocytopenia. However, the prevalence and severity of thrombocytopenia are unknown in this clinical setting. Moreover, one-third of patients after balloon-occluded retrograde transvenous obliteration (BRTO) have aggravated splenomegaly, which potentially may cause worsening thrombocytopenia. The aim of the study is to determine the prevalence and degree of thrombocytopenia in patients with gastric varices associated with gastrorenal shunts undergoing BRTO, to determine the prognostic factors of survival after BRTO (platelet count included), and to assess the effect of BRTO on platelet count over a 1-year period.

MATERIALS AND METHODS

This is a retrospective review of 35 patients who underwent BRTO (March 2008-August 2011). Pre- and post-BRTO platelet counts were noted. Potential predictors of bleeding and survival (age, gender, liver disease etiology, platelet count, model for end stage liver disease [MELD]-score, presence of ascites or hepatocellular carcinoma) were analyzed (multivariate analysis). A total of 91% (n = 32/35) of patients had thrombocytopenia (<150,000 platelet/cm(3)) pre-BRTO. Platelet counts at within 48-h, within 2 weeks and at 30-60 days intervals (up to 6 months) after BRTO were compared with the baseline pre-BRTO values.

RESULTS

35 Patients with adequate platelet follow-up were found. A total of 92% and 17% of patients had a platelet count of <150,000/cm(3) and <50,000/cm(3), respectively. There was a trend for transient worsening of thrombocytopenia immediately (<48 h) after BRTO, however, this was not statistically significant. Platelet count was not a predictor of post-BRTO rebleeding or patient survival. However, MELD-score, albumin, international normalized ratio (INR), and etiology were predictors of rebleeding.

CONCLUSION

Thrombocytopenia is very common (>90% of patients) in patients undergoing BRTO. However, BRTO (with occlusion of the gastrorenal shunt) has little effect on the platelet count. Long-term outcomes of BRTO for bleeding gastric varices using sodium tetradecyl sulfate in the USA are impressive with a 4-year variceal rebleed rate and transplant-free survival rate of 9% and 76%, respectively. Platelet count is not a predictor of higher rebleeding or patient survival after BRTO.

Ectopic varices: anatomical classification, hemodynamic classification, and hemodynamic-based management

Ectopic varices are dilated splanchnic (mesoportal) veins/varicosities and/or are dilated portosystemic collaterals that can occur along the entire gastrointestinal tract outside the common pathologic variceal sites. Ectopic varices are complex and highly variable entities that are not fully understood. Ectopic varices represent 2%-5% of a gastrointestinal tract variceal bleeding. However, ectopic varices have a 4-fold increased risk of bleeding when compared with esophageal varices and can have a mortality rate as high as 40%. All treatment strategies and techniques have been utilized in managing these potentially mortal varices and have shown poor outcomes. The debate of whether to manage these varices by decompression with a transjugular portosystemic shunt, or other portosystemic shunts, vs transvenous obliteration is unresolved. The rebleed rates after transjugular portosystemic shunt decompression are 20%-40%. The rebleed rates after transvenous obliteration and the mortality rate at 3-6 months are 30%-40% and 50%-60%, respectively. Hemodynamically from an etiology standpoint, there are 2 types: occlusive (type-b) and nonocclusive (oncotic or type-a). Hemodynamically from a vascular-shunting standpoint, there could be a component of portoportal or portosystemic shunting or both with varying dominance. This is the basis of the new classification system described herein. Management strategies (decompression vs sclerosis) are discussed. The ideal management strategy is a treatment that leads to prompt hemostasis but also addresses the etiology or hemodynamics of the ectopic varices. It is the hope that with better understanding, description, and categorization of ectopic varices comes a more systematic approach to this rare but menacing problem.

Balloon-occluded retrograde transvenous obliteration of gastric varices

Balloon-occluded retrograde transvenous obliteration (BRTO) of gastric varices is an image-guided transcatheter procedure used to treat gastric varices with sclerosants rather than decompression of the portal venous system. The history of its development, relevant portal venous, and systemic venous anatomic considerations, techniques, indications, and early results will be reviewed. In addition, the status of the practice of BRTO in the United States will be discussed.

Balloon-occluded retrograde transvenous obliteration of gastric varices

OBJECTIVE

The purpose of this review is to describe the clinical factors related to balloon-occluded retrograde transvenous obliteration, including the preparation needed, the technique and challenges, and the outcomes.

CONCLUSION

Although the procedure can be performed when transjugular intrahepatic portosystemic shunt is contraindicated or when endoscopic management fails, balloon-occluded retrograde transvenous obliteration is successful as a first-line or second-line therapy. Gastric variceal rebleeding rates are low and serious complications are rare. Randomized controlled trials are required to evaluate the superiority of this procedure over other methods of treating gastric varices and to determine which sclerosant should be used. In the near future, this procedure may play a larger role in emergency care and in the management of nongastric varices.