Propranolol plus prazosin compared with propranolol plus isosorbide-5-mononitrate in the treatment of portal hypertension

5-MTHF enhances the portal pressure reduction achieved with propranolol in patients with cirrhosis: A randomized placebo-controlled trial

BACKGROUND & AIMS

β-blockers reduce hepatic venous pressure gradient (HVPG) by decreasing portal inflow, with no reduction in intrahepatic vascular resistance. 5-Methyltetrahydrofolate (5-MTHF) can prevent oxidative loss of tetrahydrobiopterin (BH4), a cofactor for endothelial nitric oxide synthase coupling. It also converts homocysteine (tHcy) into methionine and enables the degradation of asymmetric dimethylarginine (ADMA), an inhibitor of endothelial nitric oxide synthase. The aim of this study was to evaluate the effects of 5-MTHF in combination with propranolol on HVPG and nitric oxide bioavailability markers in patients with cirrhosis and portal hypertension.

METHOD

Sixty patients with cirrhosis and HVPG ≥12 mmHg were randomized 1:1 to receive treatment with 5-MTHF+propranolol or placebo+propranolol for 90 days under double-blind conditions. HVPG and markers of nitric oxide bioavailability (BH4, ADMA and tHcy) were measured again at the end of treatment.

RESULTS

Groups were similar in terms of baseline clinical and hemodynamic data and nitric oxide bioavailability markers. HVPG decreased in both groups, but the magnitude of the change was significantly greater in the group treated with 5-MTHF+propranolol compared to placebo+propranolol (percentage decrease, 20 [29-9] vs. 12.5 [22-0], p = 0.028), without differences in hepatic blood flow. At the end of treatment, 5-MTHF+propranolol (vs. placebo+propranolol) was associated with higher BH4 (1,101.4 ± 1,413.3 vs. 517.1 ± 242.8 pg/ml, p <0.001), lower ADMA (109.3 ± 52.7 vs. 139.9 ± 46.7 μmol/L, p = 0.027) and lower tHcy (μmol/L, 11.0 ± 4.6 vs. 15.4 ± 7.2 μmol/L, p = 0.010) plasma levels.

CONCLUSION

In patients with cirrhosis and portal hypertension, 5-MTHF administration significantly enhanced the HVPG reduction achieved with propranolol. This effect appears to be mediated by improved nitric oxide bioavailability in the hepatic microcirculation.

CLINICAL TRIAL EUDRACT NUMBER

2014-002018-21.

IMPACT AND IMPLICATIONS

Currently, the pharmacological prevention of cirrhosis complications due to portal hypertension, such as esophageal varices rupture, is based on the use of β-blockers, but some patients still present with acute variceal bleeding, mainly due to an insufficient reduction of portal pressure. In this study, we sought to demonstrate that the addition of folic acid to β-blockers is more effective in reducing portal pressure than β-blockers alone. This finding could represent the basis for validation studies in larger cohorts, which could impact the future prophylactic management of variceal bleeding in cirrhosis. Enhancing the benefit of β-blockers with a safe, accessible, cost-effective drug could improve clinical outcomes in cirrhosis, which in turn could translate into a reduction in the rates and costs of hospitalization, and ultimately into improved survival.

The Efficacy of Carvedilol in Comparison to Propranolol in Reducing the Hepatic Venous Pressure Gradient and Decreasing the Risk of Variceal Bleeding in Adult Cirrhotic Patients: A Systematic Review

The most common cause of portal hypertension is liver cirrhosis. Portal hypertension causes many complications in cirrhotic patients; a significant complication is the formation of varices and the subsequent life-threatening variceal bleeding due to elevated portal venous pressures. Hepatic venous pressure gradient (HVPG) is the gold standard for measuring portal hypertension and guides management. Pharmacological treatments lower the HVPG, preventing the progression of varices and subsequent variceal bleeding. The pharmacological treatments frequently used in primary and secondary prophylaxis of a variceal bleed are nonselective beta (β)-adrenergic blockers. Propranolol was the first nonselective β-adrenergic blocker used for lowering HVPG and has been well studied. However, in the past decade, clinical trials have shown that carvedilol has been more effective. This study aims to establish whether carvedilol is more effective than propranolol in reducing the hepatic venous pressure gradient and decreasing the risk of variceal bleeding in adult cirrhotic patients. A systematic review has been conducted to gather relevant clinical trials comparing drugs and their effects on HVPG. Four databases: PubMed (Medical Literature Analysis and Retrieval System Online (MEDLINE)), Google Scholar, the Cochrane Library, and ScienceDirect, were analyzed, and records from January 1, 1999, to January 1, 2023, were chosen. There were a total of 1,235 potentially eligible records across the four databases. Using the eligibility criteria for this systematic review, seven studies of 533 patients were included. Across all seven clinical trials, it was found that carvedilol reduced HVPG more than propranolol and decreased the risk of variceal bleeding in adult cirrhotic patients.

Cirrhotic portal hypertension: From pathophysiology to novel therapeutics

Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients with cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance and a hyperdynamic circulatory state. The latter is characterized by a high cardiac output, increased total blood volume and splanchnic vasodilatation, resulting in increased mesenteric blood flow. Pharmacological manipulation of cirrhotic portal hypertension targets both the splanchnic and hepatic vascular beds. Drugs such as angiotensin converting enzyme inhibitors and angiotensin II type receptor 1 blockers, which target the components of the classical renin angiotensin system (RAS), are expected to reduce intrahepatic vascular tone by reducing extracellular matrix deposition and vasoactivity of contractile cells and thereby improve portal hypertension. However, these drugs have been shown to produce significant off-target effects such as systemic hypotension and renal failure. Therefore, the current pharmacological mainstay in clinical practice to prevent variceal bleeding and improving patient survival by reducing portal pressure is non-selective -blockers (NSBBs). These NSBBs work by reducing cardiac output and splanchnic vasodilatation but most patients do not achieve an optimal therapeutic response and a significant proportion of patients are unable to tolerate these drugs. Although statins, used alone or in combination with NSBBs, have been shown to improve portal pressure and overall mortality in cirrhotic patients, further randomized clinical trials are warranted involving larger patient populations with clear clinical end points. On the other hand, recent findings from studies that have investigated the potential use of the blockers of the components of the alternate RAS provided compelling evidence that could lead to the development of drugs targeting the splanchnic vascular bed to inhibit splanchnic vasodilatation in portal hypertension. This review outlines the mechanisms related to the pathogenesis of portal hypertension and attempts to provide an update on currently available therapeutic approaches in the management of portal hypertension with special emphasis on how the alternate RAS could be manipulated in our search for development of safe, specific and effective novel therapies to treat portal hypertension in cirrhosis.

Can We Add the History of the Nonoperative Therapy of Varices to Other Success Chapters of Modern Medicine?

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Precision medicine in variceal bleeding: Are we there yet?

Variceal bleeding is one of the most feared complications of portal hypertension in patients with cirrhosis because of its deleterious impact on prognosis. Adequate management of patients at risk of developing variceal bleeding includes the prevention of the first episode of variceal bleeding and rebleeding, and is crucial in modifying prognosis. The presence of clinically significant portal hypertension is the main factor determining the risk of development of varices and other liver-related decompensations; therefore, it should be carefully screened for and monitored. Treating patients with clinically significant portal hypertension based on their individual risk of portal hypertension-related bleeding undoubtedly improves prognosis. The evaluation of liver haemodynamics and liver function can stratify patients according to their risk of bleeding and are no question useful tools to guide therapy in an individualised manner. That said, recent data support the idea that tailoring therapy to patient characteristics may effectively impact on prognosis and increase survival in all clinical scenarios. This review will focus on evaluating the available evidence supporting the use of individual risk characteristics for clinical decision-making and their impact on clinical outcome and survival. In primary prophylaxis, identification and treatment of patients with clinically significant portal hypertension improves decompensation-free survival. In the setting of acute variceal bleeding, the risk of failure and rebleeding can be easily predicted, allowing for early escalation of treatment (i.e. pre-emptive transjugular intrahepatic portosystemic shunt) which can improve survival in appropriate candidates. Stratifying the risk of recurrent variceal bleeding based on liver function and haemodynamic response to non-selective beta-blockers allows for tailored treatment, thereby increasing survival and avoiding adverse events.

Dose-dependent effect of propranolol on the hemodynamic response in cirrhotic patients with gastroesophageal varices

OBJECTIVE

Propranolol is always titrated to the maximum tolerated dose to prevent gastroesophageal variceal bleeding. However, some patients do not achieve a hemodynamic response and experience more intolerance and discontinuation. This study evaluated the dose-dependent effect of propranolol on hemodynamic response and tolerance in cirrhotic patients.

PATIENTS AND METHODS

This retrospective study included 95 consecutive patients recruited from our prospective database. After hepatic venous pressure gradient measurement, patients received propranolol 10 mg, twice daily increased 10 mg daily until to 80 or 120 mg/day. Secondary hepatic venous pressure gradient was also measured. For nonresponders at 80 mg/day, propranolol was titrated to 120 mg/day.

RESULTS

For 58 patients, propranolol was titrated to 80 mg/day, whereas for 37 patients, it was titrated to 120 mg/day. Hemodynamic response was similar in both groups (50 vs. 54.1%, P=0.700). Eighteen of the 29 nonresponders at propranolol 80 mg/day received a dose of 120 mg/day. Two patients achieved a hemodynamic response, but two could not tolerate the dose. Nine (15.5%) patients achieved the target dose of propranolol at 80 mg/day, whereas 16 (43.2%) patients at 120 mg/day achieved this (P=0.003). The difference in patients achieving the target dose between responders and nonresponders was not significant (14 vs. 14, P=0.642). Reduction or discontinuation was required by two (6.9%) patients using 80 mg/day propranolol and six (30%) patients using 120 mg/day propranolol (P=0.032).

CONCLUSION

There is no dose-dependent effect of 80-120 mg/day of propranolol on the hemodynamic response in cirrhotic patients with gastroesophageal varices. This indicates that low-dose propranolol below the target dose might lead to a considerable hemodynamic response and is much safer and well tolerated.

Pharmacologic prevention of variceal bleeding and rebleeding

BACKGROUND

Variceal bleeding is a major complication of portal hypertension, which is associated with significant mortality. Moreover, patients surviving a variceal bleeding episode have very high risk of rebleeding, which is associated with mortality as high as that of the first bleed. Because of this, prevention of bleeding from gastroesophageal varices has been one of the main therapeutic goals since the advent of the first effective therapies for portal hypertension.

AIM

This review deals with the present day state-of-the-art pharmacological prevention of variceal bleeding in primary and secondary prophylaxis.

RESULTS

Pharmacological therapy aims to decrease portal pressure (PP) by acting on the pathophysiological mechanisms of portal hypertension such as increased hepatic vascular tone and splanchnic vasodilatation. Propranolol and nadolol block the beta-1 in the heart and the peripheral beta-2 adrenergic receptors. Beta-1 blockade of cardiac receptors reduces heart rate and cardiac output and subsequently decreases flow into splanchnic circulation. Beta-2 blockade leads to unopposed alpha-1 adrenergic activity that causes splanchnic vasoconstriction and reduction of portal inflow. Both effects contribute to reduction in PP. Carvedilol is more powerful in reducing hepatic venous pressure gradient (HVPG) than traditional nonselective beta-blockers (NSBBs) and achieves good hemodynamic response in nearly 75 % of cases. Simvastatin and atorvastatin improve endothelial dysfunction mainly by enhancing endothelial nitric oxide synthase (eNOS) expression and phosphorylation and NO production. In addition, statins deactivate hepatic stellate cells and ameliorate hepatic fibrogenesis. These effects cause a decrease in HVPG and improve liver microcirculation and hepatocyte perfusion in patients with cirrhosis. In addition, several promising drugs under development may change the management of portal hypertension in the coming years.

CONCLUSION

This review provides a background on the most important aspects of the treatment of portal hypertension in patients with compensated and decompensated liver cirrhosis. However, despite the great improvement in the prevention of variceal bleeding over the last years, further therapeutic options are needed.

Novel treatment options for portal hypertension

Portal hypertension is most frequently associated with cirrhosis and is a major driver for associated complications, such as variceal bleeding, ascites or hepatic encephalopathy. As such, clinically significant portal hypertension forms the prelude to decompensation and impacts significantly on the prognosis of patients with liver cirrhosis. At present, non-selective β-blockers, vasopressin analogues and somatostatin analogues are the mainstay of treatment but these strategies are far from satisfactory and only target splanchnic hyperemia. In contrast, safe and reliable strategies to reduce the increased intrahepatic resistance in cirrhotic patients still represent a pending issue. In recent years, several preclinical and clinical trials have focused on this latter component and other therapeutic avenues. In this review, we highlight novel data in this context and address potentially interesting therapeutic options for the future.

A randomized trial to assess whether portal pressure guided therapy to prevent variceal rebleeding improves survival in cirrhosis

Monitoring the hemodynamic response of portal pressure (PP) to drug therapy accurately stratifies the risk of variceal rebleeding (VRB). We assessed whether guiding therapy with hepatic venous pressure gradient (HVPG) monitoring may improve survival by preventing VRB. Patients with cirrhosis with controlled variceal bleeding were randomized to an HVPG-guided therapy group (N = 84) or to a control group (N = 86). In both groups, HVPG and acute β-blocker response were evaluated at baseline and HVPG measurements were repeated at 2-4 weeks to determine chronic response. In the HVPG-guided group, acute responders were treated with nadolol and acute nonresponders with nadolol+nitrates. Chronic nonresponders received nadolol+prazosin and had a third HVPG study. Ligation sessions were repeated until response was achieved. The control group was treated with nadolol+nitrates+ligation. Between-group baseline characteristics were similar. During long-term follow-up (median of 24 months), mortality was lower in the HVPG-guided therapy group than in the control group (29% vs. 43%; hazard ratio [HR] = 0.59; 95% confidence interval [CI] = 0.35-0.99). Rebleeding occurred in 19% versus 31% of patients, respectively (HR = 0.53; 95% CI = 0.29-0.98), and further decompensation of cirrhosis occurred in 52% versus 72% (HR = 0.68; 95% CI = 0.46-0.99). The survival probability was higher with HVPG-guided therapy than in controls, both in acute (HR = 0.59; 95% CI = 0.32-1.08) and chronic nonresponders (HR = 0.48; 95% CI = 0.23-0.99). HVPG-guided patients had a greater reduction of HVPG and a lower final value than controls (P < 0.05).

CONCLUSION

HVPG monitoring, by stratifying risk and targeting therapy, improves the survival achieved with currently recommended treatment to prevent VRB using β-blockers and ligation. HVPG-guided therapy achieved a greater reduction in PP, which may have contributed to reduce the risk of rebleeding and of further decompensation of cirrhosis, thus contributing to a better survival. (Hepatology 2017;65:1693-1707).

Emerging therapies for portal hypertension in cirrhosis

INTRODUCTION

Counteracting splanchnic vasodilatation and increased portal-collateral blood flow has been the mainstay for the treatment of portal hypertension (PH) over the past three decades. However, there is still large room for improvement in the treatment of PH.

AREAS COVERED

The basic mechanism leading to portal hypertension is the increased hepatic vascular resistance to portal blood flow caused by liver structural abnormalities inherent to cirrhosis and increased hepatic vascular tone. Molecules modulating microvascular dysfunction which have undergone preclinical and clinical trials are summarized, potential drug development issues are addressed, and situations relevant to design of clinical trials are considered.

EXPERT OPINION

Experimental and clinical evidence indicates that molecules modulating liver microvascular dysfunction may allow for 30-40% reduction in portal pressure. Several agents could be utilized in the earlier stages of cirrhosis (antifibrotics, antiangiogenics, etiological therapies) may allow reduction of fibrosis and halt progression of PH. This 'nip at the bud' policy, by combining therapies with existing agents used in advanced phase of cirrhosis and novel agents which could be used in early phase of cirrhotic spectrum, which are likely to hit the market soon would be the future strategy for PH therapy.

Influence of CYP2D6 and β2-adrenergic receptor gene polymorphisms on the hemodynamic response to propranolol in Chinese Han patients with cirrhosis

BACKGROUND AND AIM

Propranolol is widely used to prevent gastroesophageal variceal bleeding; however, some patients could not benefit from propranolol. This study is to evaluate the relationship between CYP2D6 and β2-adrenergic receptor (β2-AR) gene polymorphisms and the hemodynamic response to propranolol in Chinese Han patients.

METHODS

The clinical data of patients with gastroesophageal varices undergoing hepatic venous pressure gradient (HVPG) measurement before and 7 days after oral propranolol administration in our department were collected. Four single nucleotide polymorphisms of CYP2D6 and β2-AR genes were detected. The relationship was identified by logistic regression model.

RESULTS

Thirty patients were involved in the analysis. Sixty milligram propranolol twice each day was well tolerated by all the patients. The initial and secondary average of HVPG was 17.4 ± 5.8 mmHg vs. 13.2 ± 4.8 mmHg, respectively (t = 5.726, P < 0.001). Twenty patients responded to propranolol. The mean reduction value of HVPG was 6.6 ± 3.6 mmHg (range from 3 to 19). Genotype analysis showed: 20 homozygotes for C/C188 and 10 for heterozygous C/T188, 8 homozygotes for G/G4268 and 22 heterozygotes for G/C4268, 14 homozygotes for Gly16 and 10 heterozygotes, and 6 homozygotes for Arg16, 27 homozygotes for Gln27 and 3 heterozygotes. The multivariate logistic regression analysis indicated that CYP2D6 (188C>T) genotype was an independent predicting factor for HVPG response to propranolol (P = 0.033).

CONCLUSIONS

CYP2D6 (188C>T) gene polymorphisms influence the hemodynamic response to propranolol in this population of Chinese Han patients with gastroesophageal varices. However, HVPG response cannot be completely predicted from CYP2D6 and β2-AR gene polymorphisms.

The Role of Medical Therapy for Variceal Bleeding

Acute variceal hemorrhage (AVH) is a lethal complication of portal hypertension and should be suspected in every patient with liver cirrhosis who presents with upper gastrointestinal bleed. AVH-related mortality has decreased in the last few decades from 40% to 15%-20% due to advances in the general and specific management of variceal hemorrhage. This review summarizes current management of AVH and prevention of recurrent hemorrhage with a focus on pharmacologic therapy.

Pathophysiology of Portal Hypertension

The bases of our current knowledge on the physiology of the hepatic portal system are largely owed to the work of three pioneering vascular researchers from the sixteenth and the seventeenth centuries: A. Vesalius, W. Harvey, and F. Glisson. Vesalius is referred to as the founder of modern human anatomy, and in his influential book, De humani corporis fabrica libri septem, he elaborated the first anatomical atlas of the hepatic portal venous system (Vesalius 2013). Sir William Harvey laid the foundations of modern cardiovascular research with his Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (Harvey 1931) in which he established the nature of blood circulation. Finally, F. Glisson characterized the gastrointestinal-hepatic vascular system (Child 1955). These physiological descriptions were later complemented with clinical observations. In the eighteenth and nineteenth centuries, Morgagni, Puckelt, Cruveilhier, and Osler were the first to make the connection between common hepatic complications – ascites, splenomegaly, and gastrointestinal bleeding – and obstruction of the portal system (Sandblom 1993). These were the foundations that allowed Gilbert, Villaret, and Thompson to establish an early definition of portal hypertension at the beginning of the twentieth century. In this period, Thompson performed the first direct measurement of portal pressure by laparotomy in some patients (Gilbert and Villaret 1906; Thompson et al. 1937). Considering all these milestones, and paraphrasing Sir Isaac Newton, if hepatologists have seen further, it is by standing on the shoulders of giants.

Nowadays, our understanding of the pathogenesis of portal hypertension has largely improved thanks to the progress in preclinical and clinical research. However, this field is ever-changing and hepatologists are continually identifying novel pathological mechanisms and developing new therapeutic strategies for this clinical condition. Hence, the aim of this chapter is to summarize the current knowledge about this clinical condition.

Systematic review with meta-analysis: the haemodynamic effects of carvedilol compared with propranolol for portal hypertension in cirrhosis

BACKGROUND

Propranolol is recommended for prophylaxis of variceal bleeding in cirrhosis. Carvedilol is a nonselective beta-blocker with a mild anti-alfa-1-adrenergic activity. Several studies have compared carvedilol and propranolol, yielding inconsistent results.

AIM

To perform a systematic review and meta-analysis of the randomised clinical trials comparing carvedilol with propranolol for hepatic vein pressure gradient reduction.

METHODS

Studies were searched on the MEDLINE, EMBASE and Cochrane library databases up to November 2013. The weighted mean difference in percent hepatic vein pressure gradient reduction and the relative risk of failure to achieve a hemodynamic response (reduction ≥20% of baseline or to ≤12 mmHg) with each drug were used as measures of treatment efficacy.

RESULTS

Five studies (175 patients) were included. Indication to treatment was primary prophylaxis of variceal bleeding in 76% of patients. There were overall three acute (60-90 min after drug administration) and three long-term (after 7-90 days of therapy) comparisons. The summary mean weighted difference in % of reduction in hepatic vein pressure gradient was: acute -7.70 (CI -12.40, -3.00), long-term -6.81 (CI -11.35, -2.26), overall -7.24 (CI -10.50, -3.97), favouring carvedilol. The summary relative risk of failure to achieve a hemodynamic response with carvedilol was 0.66 (CI 0.44, 1.00). Adverse events were nonsignificantly more frequent and serious with carvedilol. However, quality of trials was mostly unsatisfactory.

CONCLUSIONS

Carvedilol reduces portal hypertension significantly more than propranolol. However, available data do not allow a satisfactory comparison of adverse events. These results suggest a potential for a cautious clinical use.

Carvedilol or propranolol in portal hypertension? A randomized comparison

OBJECTIVES

Carvedilol is a non-selective β-blocker with intrinsic anti-α(1)-adrenergic activity, potentially more effective than propranolol in reducing hepatic venous pressure gradient (HVPG). We compared the long-term effect of carvedilol and propranolol on HVPG and assessed whether the acute response to oral propranolol predicted the long-term HVPG response on either drug.

MATERIAL AND METHODS

HVPG was measured in 38 patients with cirrhosis and HVPG ≥ 12 mm Hg at baseline and then again 90 min after an oral dose of 80 mg propranolol. Patients were double-blinded randomized to either carvedilol (21 patients) or propranolol (17 patients) and after 90 days of treatment HVPG measurements were repeated.

RESULTS

HVPG decreased by 19.3 ± 16.1% (p < 0.01) and by 12.5 ± 16.7% (p < 0.01) in the carvedilol and propranolol groups, respectively, with no significant difference between treatment regimens (p = 0.21). Although insignificant, an acute decrease in HVPG of ≥12% was the best cut-off value to predict long-term HVPG response to propranolol when using ROC curve analysis.

CONCLUSIONS

This randomized study showed that carvedilol is at least as effective as propranolol on HVPG after long-term administration. Furthermore, a predictive value of an acute propranolol test on HVPG could not be confirmed.

Managing varices: drugs, bands, and shunts

Drugs, bands, and shunts have all been used in the treatment of varices and variceal hemorrhage and have resulted in improved outcomes. However, the specific use of each of these therapies depends on the setting (primary or secondary prophylaxis, treatment of AVH) and on patient characteristics. The indications for each are summarized in Table 4.

Carvedilol in the treatment of portal hypertension

Variceal bleeding is a major event in the natural history of end-stage liver disease with a subsequent high mortality rate. Non-selective β-blockers are currently the drugs of choice for preventing first variceal bleeding. Endoscopic rubber band ligation of high risk varices features as a first line option if cirrhotic patients cannot tolerate β-blockers. Despite adequate β-blockade, some patients may still present with variceal bleeding. The effect of carvedilol, a non-selective β and α-1 receptor-blocker, on lowering portal pressure has been investigated in several clinical trials and found to be superior to propranolol in both acute and chronic hemodynamic studies. Recently, carvedilol has also been compared with band ligation for primary prophylaxis against variceal bleeding with equivalent results to band ligation. Patient tolerance to carvedilol in advanced liver disease remains a source of concern. This review examines the place of carvedilol as an alternative to the currently recommended pharmacological therapy in prophylaxis against variceal bleeding.

Management of varices in cirrhosis

INTRODUCTION

Acute variceal bleeding is a medical emergency and one of the main causes of mortality in patients with cirrhosis. Timely and effective treatment of the acute bleeding episode results in increased survival, and appropriate prophylactic treatment can prevent bleeding or rebleeding from varices.

AREAS COVERED

We discuss the prevention of development and growth of varices, the primary and secondary prophylaxis of bleeding, the treatment of acute bleeding, and the management of gastric varices. We systematically reviewed studies, without time limits, identified through Medline and searches of reference lists, and provide an overview of the evidence underlying the -treatment options in the management of varices in cirrhosis.

EXPERT OPINION

The management of variceal hemorrhage relies on nonspecific interventions (e.g., adequate fluid resuscitation, airway protection) and on specific interventions. These are routine prophylactic antibiotics, vasoactive drugs and endoscopic treatment. Procedures such as the placement of a Sengstaken-Blakemore tube or a transjugular intrahepatic portosystemic shunt (TIPS) can be lifesaving. The primary and secondary prophylaxis of bleeding is based on nonselective beta-blockers and endoscopy, even though TIPS or, less frequently, surgery have a role in selected cases.

Clinical pharmacology of portal hypertension

Portal hypertension is an increase in pressure in the portal vein and its tributaries. It is defined as a portal pressure gradient (the difference in pressure between the portal vein and the hepatic veins) greater than 5 mm Hg. Although this gradient defines portal hypertension, a gradient of 10 mm Hg or greater defines clinically significant portal hypertension, because this pressure gradient predicts the development of varices, decompensation of cirrhosis, and hepatocellular carcinoma. The most direct consequence of portal hypertension is the development of gastroesophageal varices that may rupture and lead to the development of variceal hemorrhage. This article reviews the pathophysiologic bases of the different pharmacologic treatments for portal hypertension in patients with cirrhosis and places them in the context of the natural history of varices and variceal hemorrhage.

Role of endoscopy in primary prophylaxis for esophageal variceal bleeding

Cirrhosis is the leading cause of portal hypertension in the Western world. From a clinical standpoint, the most significant consequence of portal hypertension is the development of esophageal varices. Despite the many advances in the management of variceal bleeding, it remains a life-threatening complication of portal hypertension. Primary prophylaxis to prevent the first bleeding episode in patients with cirrhosis and esophageal varices is therefore critically important in the management of patients with cirrhosis.

Systematic review: endoscopic and imaging-based techniques in the assessment of portal haemodynamics and the risk of variceal bleeding

BACKGROUND

Invasive measurement of the hepatic venous pressure gradient (HVPG) is regarded as the gold standard for risk stratification and the evaluation of pharmaceutical agents in patients with portal hypertension.

AIM

To review the techniques for endoscopic and imaging-based assessment of portal haemodynamics, with particular emphasis on trials where the results were compared with HVPG or direct portal pressure measurement.

METHODS

Systematic search of the MEDLINE electronic database with keywords: portal hypertension, variceal bleeding, variceal pressure, endoscopic ultrasound, Doppler ultrasonography, magnetic resonance angiography, CT angiography, hepatic venous pressure gradient.

RESULTS

Computed tomography angiography and endoscopic ultrasound (EUS) have been both employed for the diagnosis of complications of portal hypertension and for the evaluation of the efficacy of endoscopic therapy. Colour Doppler ultrasonography and magnetic resonance angiography has given discrepant results. Endoscopic variceal pressure measurements either alone or combined with simultaneous EUS, correlate well with HVPG and risk of variceal bleeding and have a low interobserver variability.

CONCLUSIONS

Endoscopic and imaging-based measurements of portal haemodynamics provide an alternate means for the assessment of complications of portal hypertension. Further studies are required to validate their use in risk stratification and the evaluation of drug therapies in patients with portal hypertension.

The clinical use of HVPG measurements in chronic liver disease

Portal hypertension is a severe, almost unavoidable complication of chronic liver diseases and is responsible for the main clinical consequences of cirrhosis. Measurement of the hepatic venous pressure gradient (HVPG) is currently the best available method to evaluate the presence and severity of portal hypertension. Clinically significant portal hypertension is defined as an increase in HVPG to >or=10 mmHg; above this threshold, the complications of portal hypertension might begin to appear. Measurement of HVPG is increasingly used in clinical hepatology, and numerous studies have demonstrated that the parameter is a robust surrogate marker for hard clinical end points. The main clinical applications for HVPG include diagnosis, risk stratification, identification of patients with hepatocellular carcinoma who are candidates for liver resection, monitoring of the efficacy of medical treatment, and assessment of progression of portal hypertension. Patients who experience a reduction in HVPG of >or=20% or to <12 mmHg in response to drug therapy are defined as 'responders'. Responders have a markedly decreased risk of bleeding (or rebleeding), ascites, and spontaneous bacterial peritonitis, which results in improved survival.

Prognostic value of acute hemodynamic response to i.v. propranolol in patients with cirrhosis and portal hypertension

BACKGROUND/AIMS

Cirrhotic patients chronically treated with beta-blockers who achieve a decrease of hepatic venous pressure gradient (HVPG) > or =20% from baseline or to < or =12 mmHg have a marked reduction of first bleeding or re-bleeding. However, two HVPG measurements are needed to evaluate response. This study was aimed at investigating the predictive role of acute HVPG response to i.v. propranolol for bleeding and survival.

METHODS

We retrospectively studied 166 cirrhotic patients with varices with HVPG response to i.v. propranolol (0.15 mg/kg). All patients subsequently received non-selective beta-blockers to prevent first bleeding (n=78) or re-bleeding (n=88).

RESULTS

Thirty-seven patients developed a portal hypertension-related bleeding over 2 years of follow-up. Decrease (12%) in HVPG was the best cut-off for bleeding risk discrimination. This parameter was used to classify patients in responders (n=95) and non-responders (n=71). In primary prophylaxis (54 responders vs. 24 non-responders) the actuarial probability of bleeding was half in responders than in non-responders (12% vs. 23% at 2 years; ns). In secondary prophylaxis (41 responders vs. 47 non-responders) a good hemodynamic response was also significantly and independently associated with a 50% decrease in the probability of re-bleeding (23% at 2 years vs. 46% in non-responders; p=0.032) and a better survival (95% vs. 65%; p=0.003).

CONCLUSION

The evaluation of acute HVPG response to i.v. propranolol before initiating secondary prophylaxis for variceal bleeding is a useful tool in predicting the efficacy of non-selective beta-blockers. If adequately validated, this might be a more cost-effective strategy than the chronic evaluation of HVPG response and might be useful to guide therapeutic decisions in these patients.

Effects of probiotic therapy on portal pressure in patients with cirrhosis: a pilot study

BACKGROUND

Recent literature has supported the role of bacterial translocation as a mediator of splanchnic vasodilatation and portal hypertension. The objective of this study was to determine whether the probiotic VSL#3 would reduce portal pressure in patients with cirrhosis.

METHODS

Eight patients with compensated or very early decompensated cirrhosis and hepatic venous pressure gradient (HVPG) >10 mmHg, received 2 months of VSL#3 (3600 billion bacteria daily). The HVPG, intestinal permeability, endotoxin, tumour necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, renin and aldosterone were measured at baseline and study end.

RESULTS

There was no change in the HVPG or intestinal permeability from baseline to study end but there was a trend to reduction in plasma endotoxin (P=0.09), a mild but significant increase in serum TNF-alpha (P=0.02) and a significant reduction in plasma aldosterone (P=0.03).

CONCLUSIONS

Within the limitations of small sample size, there does not appear to be a benefit of probiotic therapy for portal pressure reduction in patients with compensated or early decompensated cirrhosis. The reductions in endotoxin and aldosterone suggest possible beneficial effects of probiotics for this patient population. The clinical significance of the small but unexpected increase in TNF-alpha is unclear. Future studies are planned in patients with decompensated cirrhosis.

Review: Vasoconstrictors for the treatment of portal hypertension

Vasoconstrictors have long been used in an attempt to mitigate the effects of portal hypertension. In this review, we discuss the current understanding of portal hypertension and the use of vasoconstrictors in the management of its sequlae, including variceal hemorrhage, hepatorenal syndrome, and paracentesis-induced circulatory dysfunction. Experimental and clinical evidence for the use of vasoconstrictors is considered, and several exciting recent developments are reviewed.

Clinical trial: a randomized controlled study on prevention of variceal rebleeding comparing nadolol + ligation vs. hepatic venous pressure gradient-guided pharmacological therapy

BACKGROUND

Hepatic venous pressure gradient (HVPG) monitoring of therapy to prevent variceal rebleeding provides strong prognostic information. Treatment of nonresponders to beta-blockers +/- nitrates has not been clarified.

AIM

To assess the value of HVPG-guided therapy using nadolol + prazosin in nonresponders to nadolol + isosorbide-5-mononitrate (ISMN) compared with a control group treated with nadolol + ligation.

METHODS

Cirrhotic patients with variceal bleeding were randomized to HVPG-guided therapy (n = 30) or nadolol + ligation (n = 29). A Baseline haemodynamic study was performed and repeated within 1 month. In the guided-therapy group, nonresponders to nadolol + ISMN received nadolol and carefully titrated prazosin and had a third haemodynamic study.

RESULTS

Nadolol + prazosin decreased HVPG in nonresponders to nadolol + ISMN (P < 0.001). Finally, 74% of patients were responders in the guided-therapy group vs. 32% in the nadolol + ligation group (P < 0.01). The probability of rebleeding was lower in responders than in nonresponders in the guided therapy group (P < 0.01), but not in the nadolol + ligation group (P = 0.41). In all, 57% of nonresponders rebled in the guided-therapy group and 20% in the nadolol + ligation group (P = 0.05). The incidence of complications was similar.

CONCLUSIONS

In patients treated to prevent variceal rebleeding, the association of nadolol and prazosin effectively rescued nonresponders to nadolol and ISMN, improving the haemodynamic response observed in controls receiving nadolol and endoscopic variceal ligation. Our results also suggest that ligation may rescue nonresponders.

Acute variceal bleeding: pharmacological treatment and primary/secondary prophylaxis

Variceal bleeding is one of the most severe complications of portal hypertension related to liver cirrhosis. Primary prophylaxis is considered mandatory in patients with cirrhosis and high-risk oesophageal varices, and once varices have bled, every effort should be made to arrest the haemorrhage and prevent further bleeding episodes. In acute variceal bleeding, vasoactive drugs that lower portal pressure should be started even before endoscopy, and should be maintained for up to 5 days. The choice of vasoactive drug should be made according to local resources. Terlipressin, somatostatin and octreotide can be used; vasopressin plus transdermal nitroglycerin may be used if no other drug is available. In variceal bleeding, antibiotic therapy is also mandatory. In primary and secondary prophylaxis, beta-blockers are the mainstay of therapy. In secondary prophylaxis (but not in primary prophylaxis) these drugs can be combined with organic nitrates.

Preventing first variceal hemorrhage in cirrhosis

Variceal bleeding is still a life-threatening complication of portal hypertension responsible for an appreciable rate of morbidity and mortality. The most appropriate treatment approach, whether drugs (nonselective beta-blockers) or endoscopic (variceal band ligation) therapy, to prevent the initial bleed, or primary prophylaxis, is an issue of controversy. Meta-analysis of randomized controlled trials indicates that banding seems to be somehow slightly more effective than beta-blockers at preventing a first bleeding episode, but this does not translate to improved survival. The firmness of this conclusion is, in addition, diminished by the small sample size and short follow-up of most studies. Moreover, adverse events due to banding are more severe than those associated with beta-blockers. Thus, beta-blockers remain as first-line therapy in patients with cirrhosis and large esophageal varices. Prophylactic therapy with beta-blockers can be considered in patients with small varices, especially in those with red signs or Child class C liver disease. The available evidence does not support the idea that organic nitrates improve the efficacy of beta-blockers in primary prophylaxis. The method used to establish the dose of beta-blockers and check its effect on hepatic venous pressure gradient (HVPG) has also been disputed. An attractive strategy is to measure the HVPG response to beta-blockers as a guide to primary prophylaxis, with the aim of switching to another therapy, that is, band ligation, in HVPG nonresponders. However, no study has yet demonstrated that banding as rescue therapy in nonresponders lowers the risk of first bleeding and improves survival.

Octreotide enhances portal pressure reduction induced by propranolol in cirrhosis: a randomized, controlled trial

BACKGROUND

In vitro, octreotide potentiates vasoconstriction in isolated, preconstricted, mesenteric arterial vessels. In cirrhotic patients, portal pressure (HVPG) reduction induced by propranolol is partly due to splanchnic vasoconstriction.

AIM

To evaluate HVPG effects of octreotide administration in cirrhotic patients receiving long-term propranolol.

PATIENTS AND METHODS

A randomized, controlled trial. First study: a total of 28 patients were studied at baseline and 30 and 60 minutes after octreotide (200 mug) (N = 14) or placebo (N = 14) and then treated with propranolol for approximately 30 days (106 +/- 5 mg/day). Second study: after baseline evaluation patients received octreotide or placebo as they were assigned to in the first study and measurements repeated 30 and 60 minutes later.

RESULTS

In the first study baseline HVPG was 18.7 +/- 0.9 mmHg and decreased to 17.1 +/- 1.1 mmHg and 17.1 +/- 1.0 mmHg (both P < 0.05 vs baseline) at 30 and 60 minutes after octreotide, respectively. Eight patients decreased their HVPG after octreotide. In the second study baseline HVPG was 15.6 +/- 1.3 mmHg (P < 0.01 vs baseline HVPG in first study) and decreased to 14.1 +/- 1.2 mmHg and 14.1 +/- 1.3 mmHg (25.7 +/- 5% lower than baseline HVPG in the first study, P < 0.01) (both P < 0.05 vs baseline) at 30 and 60 minutes after octreotide, respectively. Nine patients (2 responders/7 nonresponders to propranolol) decreased their HVPG after octreotide. Octreotide effects may be mediated by potentiation and additive mechanisms.

CONCLUSIONS

Octreotide enhances HVPG reduction induced by propranolol in cirrhotic patients.

The extent of the collateral circulation influences the postprandial increase in portal pressure in patients with cirrhosis

BACKGROUND

In cirrhosis, repeated flares of portal pressure and collateral blood flow provoked by postprandial hyperaemia may contribute to variceal dilation and rupture.

AIM

To examine the effect of the extent of the collateral circulation on the postprandial increase in portal pressure observed in cirrhosis.

PATIENTS AND METHODS

The hepatic venous pressure gradient (HVPG), hepatic blood flow and azygos blood flow were measured in 64 patients with cirrhosis before and after a standard liquid meal.

RESULTS

Peak increases in HVPG (median+14.9%), hepatic blood flow (median+25.4%), and azygos blood flow (median+32.2%) occurred at 30 min after the meal. Compared with patients with marked postprandial increase in HVPG (above the median, n = 32), those showing mild (<15%, n = 32) increase in HVPG had a higher baseline azygos flow (p<0.01) and underwent a greater postprandial increase in azygos flow (p<0.02). Hepatic blood flow increased similarly in both groups. Postprandial increases in HVPG were inversely correlated (p<0.001) with both baseline azygos flow (r = -0.69) and its postprandial increase (r = -0.72). Food intake increased nitric oxide products in the azygos (p<0.01), but not in the hepatic vein. Large varices (p<0.01) and previous variceal bleeding (p<0.001) were more frequent in patients with mild increase in HVPG.

CONCLUSIONS

Postprandial hyperaemia simultaneously increases HVPG and collateral flow. The extent of the collateral circulation determines the HVPG response to food intake. Patients with extensive collateralisation show less pronounced postprandial increases in HVPG, but associated with marked flares in collateral flow. Collateral vessels preserve their ability to dilate in response to increased blood flow.

Comparison of endoscopic variceal ligation and nadolol plus isosorbide-5-mononitrate in the prevention of first variceal bleeding in cirrhotic patients

BACKGROUND

Both drug therapy and banding ligation are widely used in the prevention of first variceal bleeding. This study compared the efficacy and safety of band ligation vs. combination of beta-blocker and nitrate for the prevention of first bleeding in patients with cirrhosis and high-risk esophageal varices.

METHODS

A total of 61 patients with cirrhosis with moderate or severe esophageal varices associated with red color signs but without history of variceal bleeding were randomized to band ligation (30 patients) or treatment with nadolol plus isosorbide-5-mononitrate (ISMN) (31 patients). In the ligation group, multiband ligator with 4 elastic bands was applied during each session. Ligation was repeated at intervals of 4 weeks until variceal obliteration was achieved. In the combination group, the dose of nadolol was sufficient to reduce the pulse rate by 25%. ISMN 1 tablet 20 mg qd or bid was administered.

RESULTS

Both groups were similar in baseline characteristics. In the ligation group, variceal obliteration was achieved in 24 patients (80%), at a mean of 3.2 +/- 0.9 ligation sessions and 11.7 +/- 3.2 elastic bands. In the combination group, the mean daily doses of nadolol and ISMN administered were 40 +/- 14 mg and 40 +/- 12 mg, respectively. During a median follow-up of approximately 23 months, 5 patients (17%) in the ligation group and 8 patients (26%) in the combination group had upper-gastrointestinal bleeding (p = 0.53). Esophageal variceal bleeding occurred in 3 patients (10%) in the ligation group and 6 (19%) in the combination group (p = 0.42). By multivariate Cox analysis, presence of ascites was the only factor predictive of variceal bleeding. Minor complications were noted in 5 patients (17%) in the ligation group and 3 (10%) in the combination group (p = 0.47). Eight patients in the ligation group and 6 in the combination group died (p = 0.49). One (3%) patient in the ligation group and 3 (10%) in the combination group died of uncontrollable variceal bleeding.

CONCLUSION

Our preliminary results suggest that endoscopic variceal ligation is similar to the combination of nadolol plus ISMN with regard to effectiveness and safety in the prevention of first variceal bleeding in patients with cirrhosis.

Portal hypertension-related bleeding: management of difficult cases

Many advances have occurred in the management of varices over the years. Guidelines based on sound evidence have been developed to manage the esophageal variceal hemorrhage. Less is known about how best to manage some of the more difficult cases of bleeding related to portal hypertension. This article reviews evidence in the hypertensive gastropathy, ectopic varices, and management of patients who are intolerant of or have not responded to beta-blocker therapy. The goal of this article is to review the sparse available evidence and to suggest reasonable management options.

Hemodynamic effects of one week of carvedilol administration on cirrhotic rats

BACKGROUND

Carvedilol is a nonselective beta-blocker with alpha(1)-adrenergic blocking activity. It has been shown to decrease portal pressure in cirrhotic patients. The current study was undertaken to evaluate the possible mechanism of carvedilol on hemodynamics in cirrhotic rats with portal hypertension produced by common bile duct ligation.

METHODS

Male Sprague-Dawley rats received either a sham operation or common bile duct ligation. Three weeks after surgery, both sham-operated and cirrhotic rats were randomly assigned to receive vehicle or carvedilol 5 mg.kg(-1).12 h(-1) by gastric gavage for 1 week. Hemodynamic measurements, serum biochemistry, serum nitrate/nitrite and 6-keto-PGF(1alpha) levels, and aortic mRNA expression of eNOS and COX-1 were performed on the eighth day after drug administration.

RESULTS

Carvedilol treatment did not affect serum biochemistry in either sham-operated or cirrhotic rats. In sham-operated rats, administration of carvedilol significantly decreased the heart rate without affecting other hemodynamic values. In contrast, in cirrhotic rats, administration of carvedilol significantly decreased the cardiac index, portal pressure, heart rate, and portal territory blood flow, and it significantly increased systemic and portal territory vascular resistances. The hepatocollateral resistance was significantly decreased, but the hepatic arterial blood showed no significant changes. In sham-operated rats treated with carvedilol, serum nitrate/nitrite and 6-keto-PGF(1alpha) levels were not affected. In contrast, cirrhotic rats receiving carvedilol showed a significant decrease in serum nitrate/nitrite and 6-keto-PGF(1alpha) levels, associated with a decrease in aortic mRNA expression of eNOS and COX-1 compared with those receiving vehicle.

CONCLUSIONS

Carvedilol decreased portal pressure through a reduction of splanchnic blood flow associated with a decrease in hepatocollateral resistance. Additionally, administration of carvedilol decreased endothelial-related vasodilatory activities.

Portal hypertension: from pathophysiology to clinical practice

Portal hypertension (PHT) is responsible for the more severe and often lethal complications of cirrhosis such as bleeding oesophageal varices, ascites, renal dysfunction and hepatic encephalopathy. Because of the combined impact of these complications, PHT remains the most important cause of morbidity and mortality in patients with cirrhosis. Over the years, it has become clear that a decrease in portal pressure is not only protective against the risk of variceal (re)bleeding but is also associated with a lower long-term risk of developing complications and an improved long-term survival. A milestone in therapy was the introduction of non-selective beta-blockers for the prevention of bleeding and rebleeding of gastro-esophageal varices. However, in practice, less than half the patients under beta-blockade are protected from these risks, supporting the overall demand for innovation and expansion of our therapeutic armamentarium. Recent advances in the knowledge of the pathophysiology of cirrhotic PHT have directed future therapy towards the increased intrahepatic vascular resistance, which, in part, is determined by an increased hepatic vascular tone. This increased vasculogenic component provides the rationale for the potential use of therapies aimed at increasing intrahepatic vasorelaxing capacity via gene therapy, liver-selective nitric oxide donors and statines on the one hand, and at antagonizing excessive intrahepatic vasoconstrictor force through the use of endothelin antagonists, angiotensin blockers, alpha(1) adrenergic antagonists or combined alpha(1)- and non-selective beta-blockers or somatostatin analogues on the other. The focus of this review is to give an update on the pathophysiology of PHT in order to elucidate these potential novel strategies subsequently.

The management of portal hypertension

Portal hypertension is an almost unavoidable complication of cirrhosis, and it is responsible for the more lethal complications of this syndrome. Appearance of these complications represents the major cause of death and liver transplantation in patients who have cirrhosis. This article highlights treatment modalities in use for managing portal hypertension and those that may be available in the future.

Increased hepatic resistance: a new target in the pharmacologic therapy of portal hypertension

Increased resistance to portal blood flow is the primary factor in the pathophysiology of portal hypertension, and is mainly determined by the morphologic changes occurring in chronic liver diseases. This is aggravated by an increased hepatic vascular tone, which results from an insufficient hepatic bioavailability of nitric oxide (NO) and an increased production of circulating and local vasoconstrictors (angiotensin, endothelin, cysteinyl-leukotrienes, and thromboxane, among others). This dynamic and reversible component provides the rationale for the use of therapies aimed at decreasing portal pressure by reducing the vascular tone. Among them, systemic and liver-selective NO donors, statins, and gene therapy with adenovirus encoding NO synthases have been used to increase NO availability with promising results. Other attempts have been the blockade of the effect of vasoconstrictors, using anti alpha-adrenergic agents and renin-angiotensin system blockers. Some of these pharmacologic approaches have already been incorporated into clinical practice while others are still under investigation.

Variceal bleeding: pharmacological therapy

The complications of portal hypertension are totally prevented if hepatic venous pressure gradient is decreased below 12 mm Hg. Besides, if this target is not achieved, a 20% decrease in portal pressure from baseline levels offers an almost total protection from variceal bleeding. This sets the rationale for drug therapy to reduce portal pressure in portal hypertension. Pharmacological therapy to decrease portal pressure includes vasoconstrictors to decrease portal blood inflow, vasodilators to decrease hepatic resistance, and combination therapy. Oral agents, such as beta-adrenergic blockers and organic nitrates, are used for long-term prevention of variceal bleeding, while parenteral agents, such as somatostatin (and analogues) and terlipressin, are used for the treatment of acute variceal bleeding.

Acute administration of carvedilol is more effective than propranolol plus isosorbide-5-mononitrate in the reduction of portal pressure in patients with viral cirrhosis

OBJECTIVE

Propranolol is known to decrease portal pressure in cirrhotic patients with portal hypertension; however, a substantial number of patients do not respond to propranolol administration. The addition of isosorbide-5-mononitrate may enhance portal pressure reduction in patients receiving propranolol. Carvedilol is a nonselective beta-blocker with alpha(1)-adrenergic blocking activity. It has been shown to decrease portal pressure in cirrhotic patients. Additionally, carvedilol has a greater portal hypotensive effect than propranolol alone in patients with cirrhosis. The current study is aimed at comparing the acute hemodynamic effects of carvedilol with the effects of propranolol plus isosorbide-5-mononitrate in patients with viral cirrhosis.

METHODS

Patients with viral cirrhosis were randomly assigned to receive an oral administration of carvedilol of 25 mg (n = 11) or an oral administration of propranolol 40 mg plus isosorbide-5-mononitrate 20 mg (n = 11). Hemodynamic values were measured at basal and 90 min after drugs administration.

RESULTS

Both carvedilol and propranolol plus isosorbide-5-mononitrate significantly decreased cardiac index, heart rate, and HVPG. The magnitude of changes in HVPG observed between the basal and after drugs administration was greater in patients receiving carvedilol than in those receiving propranolol plus isosorbide-5-mononitrate (-18.6 +/- 3.6%vs-10.1 +/- 3.6%, p < 0.05). Hepatic blood flow increased following carvedilol administration but remained unchanged in patients receiving propranolol plus isosorbide-5-mononitrate. The magnitude of decrease in mean arterial pressure (MAP) did not differ between the two groups of patients.

CONCLUSION

In our patients with viral cirrhosis, carvedilol is more effective than propranolol plus isosorbide-5-mononitrate in the reduction of HVPG. Carvedilol administration causes an increase in hepatic blood flow, but its systemic effects were similar to those of propranolol plus isosorbide-5-mononitrate.

The cost-effectiveness of hepatic venous pressure gradient monitoring in the prevention of recurrent variceal hemorrhage

OBJECTIVE

Recurrent variceal hemorrhage is common following an initial bleed in patients with cirrhosis. The current standard of care for secondary prophylaxis is endoscopic band ligation (EBL). Combination of beta-blocker and nitrate therapy, guided by hepatic venous pressure gradient (HVPG) monitoring, is a novel alternative strategy. We sought to determine the cost-effectiveness of these competing strategies.

METHODS

Decision analysis with Markov modeling was used to calculate the cost-effectiveness of three competing strategies: (1) EBL; (2) beta-blocker and nitrate therapy without HVPG monitoring (HVPG-); and (3) beta-blocker and nitrate therapy with HVPG monitoring (HVPG+). Patients in the HVPG+ strategy who failed to achieve an HVPG decline from medical therapy were offered EBL. Cost estimates were from a third-party payer perspective. The main outcome measure was the cost per recurrent variceal hemorrhage prevented.

RESULTS

Under base-case conditions, the HVPG+ strategy was the most effective yet most expensive approach, followed by EBL and HVPG-. Compared to the EBL strategy, the HVPG+ strategy cost an incremental 5,974 dollars per recurrent bleed prevented. In a population with 100% compliance with all therapies, the incremental cost of HVPG-versus EBL fell to 5,270 dollars per recurrent bleed prevented. The model results were sensitive to the cost of EBL, the cost of HVPG monitoring, and the probability of medical therapy producing an adequate HVPG decline.

CONCLUSIONS

Compared to EBL for the secondary prophylaxis of variceal rebleeding, combination medical therapy guided by HVPG monitoring is more effective and only marginally more expensive.

The role of vasoactive drugs in the treatment of oesophageal varices

Oesophageal varices are among the most important clinical consequences of portal hypertension. Recent progress in the knowledge of the pathophysiology of portal hypertension has led to the concept that it results from the increase of sinusoidal resistance and the increase in portal blood inflow consequent to splanchnic vasodilatation. Vasoactive drugs have therefore been evaluated, aiming to restore the imbalance between the increased intrahepatic and the decreased splanchnic vascular resistance. A large number of randomised, controlled trials have shown that vasoactive drugs in single or combination therapy, significantly reduce the risk of the first bleeding and rebleeding from oesophageal varices. Vasoactive drugs are also effective and safe in controlling acute variceal bleeding. Because of their high clinical efficacy, safety, ease of use and low cost, vasoactive drugs should be considered the first choice treatment for oesophageal varices.

Maintenance of hemodynamic response to treatment for portal hypertension and influence on complications of cirrhosis

BACKGROUND/AIMS

Following treatment with beta blockers in patients with cirrhosis and portal hypertension, reduction of hepatic venous pressure gradient (HVPG) to <12 mmHg or by >20% of baseline induces an extremely low risk of variceal bleeding. However, several factors such as compliance to therapy or alcohol abstinence may change the initial response after a long follow-up, and the effect of response on other complications of cirrhosis is less clear. The aim of this study was to assess the long-term maintenance of hemodynamic response and its influence on complications of cirrhosis.

METHODS

One hundred and thirty two cirrhotic patients received nadolol and isosorbide mononitrate to prevent variceal rebleeding. HVPG was measured at baseline, after 1 to 3 months under treatment and again 12 to 18 months later.

RESULTS

Sixty four patients were responders. After a longer follow-up, earlier response did not change in 81% of cases. Changes of response were mainly related to modifications in medication dose or in alcohol intake. As compared with poor-responders, responders had a lower probability of developing ascites (P<0.001) and related conditions, a greater improvement of Child-Pugh score (P=0.03), and a lower likelihood of developing encephalopathy (P=0.001) and of requiring liver transplantation (P=0.002). Eleven responders and 22 poor-responders died (P=0.029).

CONCLUSIONS

Hemodynamic response to treatment of portal hypertension is usually sustained after a long-term follow-up. Response decreases the probability of developing complications of cirrhosis and the need for liver transplantation, and significantly improves survival.

Cost-effectiveness of hepatic venous pressure gradient measurements for prophylaxis of variceal re-bleeding

BACKGROUND

Measurement of the hepatic venous pressure gradient may identify a sub-optimal response to drug prophylaxis in patients with a history of variceal bleeding. However, the cost-effectiveness of routine hepatic venous pressure gradient measurements to guide secondary prophylaxis has not been examined.

METHODS

A Markov model was constructed using specialized software (DATA 3.5, Williamstown, MA, USA). Three strategies involved secondary prophylaxis without haemodynamic monitoring using beta-blockers alone, beta-blockers plus isosorbide mononitrate or endoscopic variceal ligation alone. Four strategies involved secondary prophylaxis with beta-blockers plus isosorbide mononitrate or beta-blockers alone, accompanied by one or two hepatic venous pressure gradient measurements to identify haemodynamic non-responders, who underwent endoscopic variceal ligation as an alternative. The total expected costs, variceal bleeding episodes and total deaths were calculated for each strategy over 3 years.

RESULTS

The two most effective strategies were combination therapy alone and combination therapy with two hepatic venous pressure gradient measurements. The incremental cost-effectiveness ratio of the latter strategy was 136,700 dollars per year of life saved compared with combination therapy alone. The ratio improved as the time horizon was extended or the rates of variceal re-bleeding were increased.

CONCLUSIONS

The cost-effectiveness of haemodynamic monitoring to guide secondary prophylaxis of recurrent variceal bleeding is highly dependent on local hepatic venous pressure gradient measurement costs, life expectancy and re-bleeding rates.

A pilot study to investigate the use of oxpentifylline (pentoxifylline) and thalidomide in portal hypertension secondary to alcoholic cirrhosis

BACKGROUND

Tumour necrosis factor-alpha is thought to be important in the pathogenesis of portal hypertension. Oxpentifylline (pentoxifylline) and thalidomide inhibit endotoxin-induced tumour necrosis factor-alpha production in vitro.

AIMS

To assess the toxicity of oxpentifylline (pentoxifylline) and thalidomide in cirrhosis and their effect on the hepatic venous pressure gradient and tumour necrosis factor-alpha production.

METHODS

In an open-label pilot study, 20 abstinent patients with stable alcoholic cirrhosis and oesophageal varices were recruited; 12 patients completed haemodynamic measurements before and after treatment with oxpentifylline (pentoxifylline) 1800 mg (n=6) or thalidomide 200 mg (n=6) daily for 2 weeks. Tumour necrosis factor-alpha production was assessed in ex vivo monocyte cultures stimulated with endotoxin.

RESULTS

Thalidomide reduced the hepatic venous pressure gradient from 19.7 mmHg (9.3-23.5 mmHg) to 12.2 mmHg (4.7-19.5 mmHg) (P=0.03) without reducing the hepatic blood flow or altering systemic haemodynamic parameters. Thalidomide reduced ex vivo tumour necrosis factor-alpha production by approximately 50%. Oxpentifylline (pentoxifylline) had no significant effect on any of the parameters measured. Side-effects led to dose reduction or treatment withdrawal in 40% of patients.

CONCLUSION

Thalidomide, but not oxpentifylline (pentoxifylline), reduces the hepatic venous pressure gradient in stable alcoholic cirrhotics, an effect that may be mediated by the inhibition of tumour necrosis factor-alpha production. The role of tumour necrosis factor-alpha inhibitory drugs in the therapy of portal hypertension should be investigated in a randomized controlled trial.