Beta-blockers in cirrhosis and refractory ascites: a retrospective cohort study and review of the literature

Association of non-selective β blockers with the development of renal dysfunction in liver cirrhosis: a systematic review and meta-analysis

BACKGROUND & AIMS

Non-selective β blockers (NSBBs) may negatively influence renal function through decreasing heart rate and cardiac output. This study aimed to systematically investigate their association.

METHODS

PubMed, EMBASE, and Cochrane library databases were searched to identify all relevant studies evaluating the association of NSBBs with renal dysfunction in cirrhotic patients. Unadjusted and adjusted data were separately extracted. Odds ratios (ORs) and hazard ratios (HRs) were pooled. Subgroup meta-analyses were performed according to the proportions of ascites and Child-Pugh class B/C and the mean model for end-stage liver disease (MELD) score. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework.

RESULTS

Fourteen studies were finally included. Based on unadjusted data, NSBBs significantly increased the risk of developing renal dysfunction (OR = 1.49; p = 0.03), and this association remained significant in subgroup analyses of studies where the proportions of ascites was >70% and Child-Pugh class B/C was 100%. Based on adjusted data with propensity score matching (adjusted OR = 0.61; p = 0.08) and multivariable regression modelling (adjusted HR = 0.86; p = 0.713), NSBBs did not increase the risk of developing renal dysfunction, and this association remained not significant in subgroup analyses of studies where the proportions of ascites was >70% and <70%, the proportion of Child-Pugh class B/C was <100%, and the mean MELD score was <15. The quality of evidence was very low for all meta-analyses.

CONCLUSIONS

NSBBs may not be associated with the development of renal dysfunction in liver cirrhosis. However, more evidence is required to clarify their association in specific populations.

Interventional Management of Portal Hypertension in Cancer Patients

PURPOSE OF REVIEW

To provide an overview of the classifications and clinical hallmarks of common cancer-related conditions that contribute to the high incidence of portal hypertension in this population and provide an update on currently available interventional radiology therapeutic approaches.

RECENT FINDINGS

In the last few decades, there have been significant advancements in understanding the pathophysiology of portal hypertension. This knowledge has led to the development of safer and more effective minimally invasive approaches. The main objective is to provide alternatives to prevent life-threatening complications from clinically significant portal hypertension and to allow the continuation of cancer treatment interventions that would otherwise be stopped. Clinicians involved in cancer care should be aware of risk factors, associated complications, and management of portal hypertension in cancer patients. Interventional radiology offers minimally invasive alternatives that play a central role in improving clinical outcomes and survival of these patients, allowing the continuation of cancer treatments.

Non-selective beta-blockers in patients with ascites: The complex interplay among the liver, kidney and heart

Non-selective beta-blockers (NSBBs) are the cornerstone of the primary and secondary prophylaxis of variceal bleeding in cirrhotic patients. They additionally prevent ascites development and death in compensated patients with clinically significant portal hypertension. After ascites onset, NSBBs remain beneficial for preventing further decompensations. However, as the cirrhosis progresses, the inflammation increases, systemic vasodilatation worsens, ascites turns refractory and cardiodynamic equilibrium becomes extremely fragile. In this scenario, NSBBs can critically impair the cardiac reserve and facilitate a haemodynamic breakdown, imperilling renal perfusion. Consequently, NSBB treatment should be carefully monitored or even avoided in such patients, and other options for portal hypertension management should be considered. In the present review, we explore the effects of NSBBs in patients with ascites and discuss the complex interplay among their hepatic, systemic and renal haemodynamic effects in this scenario.

Management of Portal Hypertension

Portal hypertension is the cause of the clinical complications associated with cirrhosis. The primary complications of portal hypertension are ascites, acute variceal bleed, and hepatic encephalopathy. Hepatic venous pressure gradient measurement remains the gold standard test for diagnosing cirrhosis-related portal hypertension. Hepatic venous pressure gradient more than 10 mmHg is associated with an increased risk of complications and is termed clinically significant portal hypertension (CSPH). Clinical, laboratory, and imaging methods can also aid in diagnosing CSPH non-invasively. Recently, deep learning methods have been demonstrated to diagnose CSPH effectively. The management of portal hypertension is always individualized and is dependent on the etiology, the availability of therapies, and the degree of portal hypertension complications. In this review, we discuss the diagnosis and management of cirrhosis-related portal hypertension in detail. Also, we highlight the history of portal hypertension and future research areas in portal hypertension.

Use of Nonselective β-Blockers in Patients With End-Stage Liver Disease and Select Complications

Objective: To review the literature and recommendations for nonselective β-blockers (NSBBs) in the setting of variceal bleeding prophylaxis and decompensated liver disease. Data Sources: Literature search of MEDLINE was performed (1988 to October 2019) using the following search terms: cirrhosis, advanced cirrhosis, β-blocker, decompensation, prophylaxis. Abstracts, peer-reviewed publications, clinical practice guidelines, and product monographs were reviewed. Study Selection and Data Extraction: Relevant English language studies and those conducted in humans were considered for analysis and inclusion. Data Synthesis: Evidence that suggests that NSBBs are harmful in advanced cirrhosis is overshadowed by confounding variables and small patient populations. The majority of the available evidence suggests neutral or beneficial effects on mortality with continuation of NSBBs despite liver disease progression. Based on the available literature, guidelines, and expert consensuses, NSBBs can be considered within this patient population and may have a positive impact on the majority of these patients. Relevance to Patient Care and Clinical Practice: This review summarizes current place in therapy for NSBBs in the setting of cirrhosis and variceal bleeding prophylaxis. It also includes a discussion of the literature for use of NSBBs within the setting of different acute decompensations in which the data and recommendations for use are less clear. Conclusions: Recent evidence shows neutral or positive results for NSBB use in particular decompensation subgroups, which suggests that NSBBs can be used cautiously with close monitoring in patients with advanced cirrhosis. Questions still remain regarding optimal agent and dose and whether agents can be safely restarted after an acute decompensation episode.

Effect of Nonselective β-Blockers on Mortality in Patients With End-Stage Cirrhosis

Background: Data regarding safety of nonselective β-blockers (NSBBs) in patients with end-stage cirrhosis are conflicting, making it difficult for practitioners to justify if benefits outweigh the risks. Objective: Evaluate the effect of NSBB use on mortality in patients with end-stage cirrhosis. Methods: We performed a dual-center retrospective study of patients who received octreotide for a variceal bleed. Patients were stratified into 2 groups based on whether or not a NSBB was prescribed at hospital discharge. The primary outcome was 24-month mortality. Multivariable logistic regression, with 24-month mortality as the dependent variable, was performed to identify independent risk factors for the primary outcome. Results: 255 patients met inclusion criteria; 24-month mortality was 32.8%. The NSBB and no-NSBB groups had similar mortality rates at 24 months (32.0% vs 38.5%, P = 0.51). Mortality at 3 months (11.6% vs 23.3%, P = 0.08) and 12 months (22.2% vs 30.0%, P = 0.36) were similar, and there were no differences in rate of variceal bleeding (22.7% vs 13.3%, P = 0.34) or cirrhosis-related cause of death (20.4% vs 23.3%, P = 0.81). In the multivariable model, age, model for end-stage liver disease with sodium and hepatocellular carcinoma were independent risk factors for 24-month mortality. NSBB therapy had no effect on 24-month mortality (adjusted odds ratio = 1.05; 95% CI = 0.32 to 3.40). Conclusion and Relevance: In patients with end-stage cirrhosis, use of NSBBs did not affect 24-month mortality. More research is needed to determine when, and if, NSBBs should be discontinued in end-stage cirrhosis.

Assessing the safety of beta-blocker therapy in cirrhosis patients with ascites: A meta-analysis

BACKGROUND & AIMS

Beta-blocker therapy is effective at reducing risks of variceal bleeding. However, beta-blockers may detrimentally exacerbate the underlying haemodynamic changes in cirrhosis. A systematic review and meta-analysis was performed to evaluate impact of beta-blockers on all-cause mortality among cirrhosis patients with ascites.

METHODS

A literature search identified studies that evaluated beta-blocker vs no beta-blocker therapy in cirrhosis patients with ascites. The primary outcome was all-cause mortality with subcohort analysis of patients with refractory or severe ascites. Quality of observational studies was assessed with Newcastle-Ottawa Scale and overall certainty of the evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

RESULTS

Eight observational studies, representing 3627 cirrhosis patients with ascites (1630 treated with beta-blockers and 1997 not treated), were included. Pooled all-cause mortality was 38.6% in beta-blocker group vs 42.2% in no beta-blocker group (RR 0.93, 95% CI 0.77-1.13, χ²  = 54.03, I²  = 87%). Subcohort analysis of cirrhosis patients with refractory or severe ascites demonstrated 33.3% mortality in beta-blocker group vs 32.1% in no beta-blocker group (RR 0.99, 95% CI 0.70-1.40, χ²  = 32.99, and I²  = 82%). Three studies were good quality and five studies were fair quality. GRADE rating was 'very low' certainty of evidence, given concern for bias and inconsistency stemming from significant heterogeneity.

CONCLUSION

No significant increase in all-cause mortality was observed in cirrhosis patients with ascites treated with beta-blockers. However, given the low certainty of the evidence, high quality prospective studies are needed.

Curcumin and α/β-Adrenergic Antagonists Cotreatment Reverse Liver Cirrhosis in Hamsters: Participation of Nrf-2 and NF-κB

Liver cirrhosis is the result of an uncontrolled fibrogenetic process, due to the activation and subsequent differentiation into myofibroblasts of the hepatic stellate cells (HSC). It is known that HSC express adrenoreceptors (AR), and the use of AR antagonists protects experimental animals from cirrhosis. However, several studies suggest that the toxicity generated by metabolism of these antagonists would hinder its use in cirrhotic patients. In addition, liver fibrosis may be associated with a decrease of the antioxidant response of the nuclear factor erythroid 2-related factor 2 (Nrf-2) and the overregulation of the proinflammatory pathway of nuclear factor kappa B (NF-κB). Therefore, in the present work, the capacity of doxazosin (α1 antagonist), carvedilol (nonselective beta-adrenoceptor blocker with alpha 1-blocking properties), and curcumin (antioxidant and anti-inflammatory compound) to reverse liver cirrhosis and studying the possible modulation of Nrf-2 and NF-κB were evaluated. Hamsters received CCl4 for 20 weeks, and then treatments were immediately administered for 4 weeks more. The individual administration of doxazosin or carvedilol showed less ability to reverse cirrhosis in relation to concomitantly curcumin administration. However, the best effect was the combined effect of doxazosin, carvedilol, and curcumin, reversing liver fibrosis and decreasing the amount of collagen I (Sirius red stain) without affecting the morphology of hepatocytes (hematoxylin and eosin stain), showing normal hepatic function (glucose, albumin, AST, ALT, total bilirubin, and total proteins). In addition, carvedilol treatment and the combination of doxazosin with curcumin increased Nrf-2/NF-κB mRNA ratio and its protein expression in the inflammatory cells in the livers, possibly as another mechanism of hepatoprotection. Therefore, these results suggest for the first time that α/β adrenergic blockers with curcumin completely reverse hepatic damage, possibly as a result of adrenergic antagonism on HSC and conceivably by the increase of Nrf-2/NF-κB mRNA ratio.

Low-Dose Propranolol as Secondary Prophylaxis for Varix Bleeding Decreases Mortality and Rebleeding Rate in Patients with Tense Ascites

Background and Aim: The risk and benefit of non-selective propranolol in patients with tense ascites are controversial. This study aimed to investigate the effect of propranolol as secondary prophylaxis on varix rebleeding and overall mortality in patients with tense ascites. Methods: This study used a database of the Health Insurance Review and Assessment Service (HIRAS), which provides health insurance to 97.2% of the total population in Korea. A total of 80,071 patients first variceal bleeding as the first decompensated complication enrolled from 2007 to 2014. Results: There were 2274 patients with large-volume ascites prescribed propranolol as secondary prophylaxis after first varix bleeding. The average prescription dose of propranolol as secondary prophylaxis was 74 mg/day in patients with large-volume ascites. The mean duration of rebleeding was 22.8 months. Result of analysis showed that low-dose propranolol (40–120 mg/day) compared to inadequate propranolol dose (<40 mg/day) as secondary prophylaxis decreased overall mortality and varix rebleeding in patients with tense ascites. Conclusions: Low-dose propranolol (40–120 mg/day) as secondary prophylaxis for variceal re-bleeding decreased overall mortality and varix rebleeding recurrence in patients with tense ascites.

Nonselective Beta-Blockers Do Not Affect Survival in Cirrhotic Patients with Ascites

BACKGROUND

The role of nonselective beta-blockers in cirrhotic patients with ascites has been recently questioned; however, definitive evidence in this regard is still lacking.

AIMS

To analyze published data on the influence of nonselective beta-blockers as compared to control group on survival of cirrhotic patients with ascites.

METHODS

Computerized bibliographic search on the main databases was performed. Hazard ratios from Kaplan-Meier curves were extracted in order to perform an unbiased comparison of survival estimates. Secondary outcomes were mortality in patients with refractory ascites, pooled rate of nonselective beta-blockers interruption, spontaneous bacterial peritonitis and hepato-renal syndrome incidence.

RESULTS

Three randomized controlled trials and 13 observational studies with 8279 patients were included. Overall survival was comparable between the two groups (hazard ratio = 0.86, 0.71-1.03, p = 0.11). Study design resulted as the main source of heterogeneity in sensitivity analysis and meta-regression. Mortality in refractory ascites patients was similar in the two groups (odds ratio = 0.90, 0.45-1.79; p = 0.76). No difference in spontaneous bacterial peritonitis (odds ratio = 0.78, 0.47-1.29, p = 0.33) and hepato-renal syndrome incidence (odds ratio = 1.22, 0.48-3.09; p = 0.67) was observed. Pooled rate of nonselective beta-blockers interruption was 18.6% (5.2-32.1%).

CONCLUSIONS

Based on our findings, nonselective beta-blockers should not be routinely withheld in patients with cirrhosis and ascites, even if refractory.

Beta-blockers in patients with advanced liver disease: Has the dust settled?

Nonselective beta-blockers (NSBBs) have been the backbone for the treatment of portal hypertension in cirrhosis for the last 3 decades. A publication in 2010 of a prospective observational study suggested that NSBBs could increase mortality in patients with refractory ascites. This opened a controversy about the safety and efficacy of NSBBs in patients with advanced liver disease and led to the publication of a large corpus of observational data assessing the safety of NSBBs in patients with advanced cirrhosis. In this article, we briefly review the clinical pharmacology of NSBBs, the pathophysiological basis for the underlying benefits and harms of NSBBs in advanced cirrhosis, and the evidence in favor and against the use of NSBBs in specific scenarios. Finally, we summarize the current recommendations and propose areas of opportunity for future research. Liver Transplantation 23 1058-1069 2017 AASLD.

Beta adrenergic blockade and decompensated cirrhosis

Non-selective betablockers (NSBBs) remain the cornerstone of medical treatment of portal hypertension. The evidence for their efficacy to prevent variceal bleeding is derived from prospective trials, which largely excluded patients with refractory ascites and renal failure. In parallel to the increasing knowledge on portal hypertension-induced changes in systemic hemodynamics, cardiac function, and renal perfusion, emerging studies have raised concerns about harmful effects of NSBBs. Clinicians are facing an ongoing controversy on the use of NSBBs in patients with advanced cirrhosis. On the one hand, NSBBs are effective in preventing variceal bleeding and might also have beneficial non-hemodynamic effects, however, they also potentially induce hypotension and limit the cardiac reserve. An individualized NSBB regimen tailored to the specific pathophysiological stage of cirrhosis might optimize patient management at this point. This article aims to give practical recommendations on the use of NSBBs in patients with decompensated cirrhosis.

Non-selective β-blockers in advanced cirrhosis: a critical review of the effects on overall survival and renal function

Introduction

Non-selective β-blockers (NSBBs) are widely prescribed in patients with cirrhosis for primary and secondary prophylaxis of bleeding oesophageal varices. Furthermore, it has been suggested that the clinical benefits of NSBBs may extend beyond their haemodynamic effects. Recently, a potentially harmful effect has been described in patients with refractory ascites or spontaneous bacterial peritonitis.

Methodology

A comprehensive literature search on β-blockers and cirrhosis survival using the electronic databases PubMed/MEDLINE, AMED, CINAHL and the Cochrane Central Register of Controlled Trials. Full-text manuscripts published over more than 35 years, from 1980 to April 2016 were reviewed for relevance and reference lists were cross-checked for additional pertinent studies regarding potential NSBB effects, especially focused on those concerned with survival and/or acute kidney injury (AKI).

Discussion

The proposed review will be able to provide valuable evidence to help decision making in the use of NSBB for the treatment of advanced cirrhosis and highlights some limitations in existing evidence to direct future research.

Rethinking the role of non-selective beta blockers in patients with cirrhosis and portal hypertension

Non-selective beta blockers (NSBB) are commonly used to prevent portal hypertensive bleeding in cirrhotics. Nevertheless, in the last years, the use of NSBB in critically decompensated patients, especially in those with refractory ascites, has been questioned, mainly for an increased risk of mortality and worsening of systemic hemodynamics. Moreover, even if NSBB have been reported to correlate with a higher risk of renal failure and severe infection in patients with advanced liver disease and hypotension, their use has been associated with a reduction of risk of spontaneous bacterial peritonitis, modification of gut permeability and reduction of bacterial translocation. This manuscript systematically reviews the published evidences about harms and benefits of the use of NSBB in patients with decompensated cirrhosis.

Nonselective β-Blockers and Survival in Patients With Cirrhosis and Ascites: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Nonselective β-blockers (NSBBs), given to reduce the risk of variceal bleeding, have been associated with increased mortality in patients with cirrhosis and refractory ascites in some, but not all, studies. We performed a systematic review and meta-analysis to evaluate the effect of NSBBs on all-cause mortality in patients with cirrhosis and refractory ascites.

METHODS

We performed a comprehensive search of MEDLINE, Embase, Web of Science, and Scopus databases through January 2015, supplemented with a manual search. Trial-specific risk ratios (RRs) were pooled using the random-effects model.

RESULTS

Our analysis included 3 randomized control trials and 8 observational studies of propranolol, carvedilol, nadolol, and metoprolol, reporting 1206 deaths among 3145 patients with ascites. The control groups received other interventions to prevent variceal bleeding. NSBB use was not associated with increased all-cause mortality in all patients with ascites (RR, 0.95; 95% confidence interval [CI], 0.67-1.35); nonrefractory ascites alone (RR, 0.96; 95% CI, 0.50-1.82), or refractory ascites alone (RR, 0.95; 95% CI, 0.57-1.61). Results were similar in randomized controlled trials and observational studies. Use of NSBBs was not associated with increased mortality at 6, 12, 18, and 24 months. Overall, the included studies had a medium to high risk of bias, except for 3 clinical trials in which the risk of biased was determined to be low.

CONCLUSIONS

The use of NSBBs was not associated with a significant increase in all-cause mortality in patients with cirrhosis and ascites or refractory ascites. Certainty in the available estimates is low; a randomized trial of only patients with ascites is needed to answer this question. This meta-analysis does not support the position that NSBBs routinely be withheld from patients with ascites.

Non-selective beta-blockers in cirrhosis: Current concepts and controversies

Non-selective beta-blockers (NSBBs) have been at the forefront in the management of portal hypertension in liver cirrhosis for the last three decades, a trusty component in the armamentarium of the Hepatologist. The role of beta-blockers has been cemented for years in cardiac disease including angina, hypertension and in heart failure, however NSBBs with their non-selective effects on β1 and β2 receptors have led to them fondly being termed “the hepatologist’s aspirin”. NSBBs’ role in reduction of portal pressure in the setting of primary and secondary prophylaxis for variceal haemorrhage has been well established. NSBBs include propranolol, nadolol and carvedilol - with the latter having been shown to be effective in patients who often fail to demonstrate a haemodynamic response to propranolol. Recent observational studies however have served for the Hepatology community to question the beneficial role of NSBBs in portal hypertension, especially in advanced cases with refractory ascites. The deleterious effect in patients with refractory ascites in a few studies led to a U-turn in clinical practice, with some in the Hepatology community withdrawing their usage in patients with advanced cirrhosis. This also led to the “window hypothesis” suggesting there may be only be a finite time frame when NSBBs have a beneficial effect in portal hypertension. The window hypothesis proposed the window for the benefits of NSBBs is closed in early portal hypertension, opening as portal hypertension progresses with it closing in advanced liver disease. The window was proposed to close in conditions such as refractory ascites or spontaneous bacterial peritonitis when patients may not necessarily mount a compensatory haemodynamic response when on NSBBs. Some centres however have continued the practice of NSBBs in advanced cirrhosis with published data challenging the scepticisms of other groups who stop NSBBs. Thus the debate, like the window hypothesis has opened, with more questions to be answered about NSBB’s mechanism of action not only in reducing portal hypertension but also their effects on systemic haemodynamics and on the pro-inflammatory pathways often activated in cirrhosis especially in advanced disease. This article serves to review the role of NSBBs in the management of portal hypertension/cirrhosis and concentrate on current concepts and controversies in this field.

Treatment with non-selective beta blockers is associated with reduced severity of systemic inflammation and improved survival of patients with acute-on-chronic liver failure

BACKGROUND & AIMS

Non-selective beta blockers (NSBBs) have been shown to have deleterious outcomes in patients with refractory ascites, alcoholic hepatitis and spontaneous bacterial peritonitis leading many physicians to stop the drug in these cases. Acute-on-chronic liver failure (ACLF) is characterized by systemic inflammation and high mortality. As NSBBs may have beneficial effects on gut motility and permeability and, systemic inflammation, the aims of this prospective, observational study were to determine whether ongoing use of NSBBs reduced 28-day mortality in ACLF patients.

METHODS

The study was performed in 349 patients with ACLF included in the CANONIC study, which is a prospective observational investigation in hospitalized cirrhotic patients with acute deterioration. The data about the use of NSBBs, its type and dosage was specifically recorded. Patient characteristics at enrollment significantly associated with treatment and mortality were taken into account as potential confounders to adjust for treatment effect. A logistic regression model was fitted.

RESULTS

164 (47%) ACLF patients received NSBBs whereas 185 patients did not. Although the CLIF-C ACLF scores were similar at presentation, more patients in the NSBB treated group had lower grades of ACLF (p=0.047) at presentation and significantly more patients improved. Forty patients (24.4%) died in NSBB treated group compared with 63 patients (34.1%) (p=0.048) [estimated risk-reduction 0.596 (95%CI: 0.361-0.985; p=0.0436)]. This improvement in survival was associated with a significantly lower white cell count (NSBB: 8.5 (5.8); no NSBB: 10.8 (6.6); p=0.002). No long-term improvement in survival was observed.

CONCLUSIONS

This study shows for the first time that ongoing treatment with NSBBs in cirrhosis is safe and reduces the mortality if they develop ACLF. Careful thought should be given before stopping NSBBs in cirrhotic patients.

Varices and Variceal Hemorrhage in Cirrhosis: A New View of an Old Problem

The management of portal hypertension in cirrhosis has evolved over time, leading to improvements in the care and survival of patients with varices and variceal hemorrhage, particularly in patients who achieve a significant reduction in portal pressure. In addition to better treatment strategies and improved therapeutic options, the issue of risk stratification has become essential to identify different patient subpopulations that require a different treatment. We now recognize that the management of varices and variceal hemorrhage must be taken in the context of other complications of cirrhosis (ascites, encephalopathy, jaundice) and that the goals of therapy should be based on the presence of such complications. Evolving knowledge of the predominant pathophysiological mechanisms at each of the stages of cirrhosis also has evolved and will continue to lead to improvements in therapy. This review focuses on the management of varices and variceal hemorrhage with respect to refinements in the risk stratification of patients with cirrhosis.

Complications of cirrhosis. A 50 years flashback

In patients with cirrhosis and portal hypertension, it is largely the frequency and severity of complications relating to the diseased liver, degree of portal hypertension and hemodynamic derangement that determine the prognosis. It can be considered as a multiple organ failure that apart from the liver involves the heart, lungs, kidneys, the immune systems and other organ systems. Progressive fibrosis of the liver and subsequent metabolic impairment leads to a systemic and splanchnic arteriolar vasodilatation. With the progression of the disease development of portal hypertension leads to formation of esophageal varices and ascites. The circulation becomes hyperdynamic with cardiac, pulmonary as well as renal consequences for dysfunction and reduced survival. Infections and a changed cardiac function known as cirrhotic cardiomyopathy may be involved in further aggravation of other complications such as renal failure precipitating the hepatorenal syndrome. Patients with end-stage liver disease and related complications as for example the hepatopulmonary syndrome can only radically be treated by liver transplantation.