Enhancement of portal pressure reduction by the association of isosorbide-5-mononitrate to propranolol administration in patients with cirrhosis

Carvedilol as secondary prophylaxis for variceal bleeding in hepatosplenic schistosomiasis

Background

Upper variceal bleeding (UVB) is a possible complication of portal hypertension secondary to hepatosplenic schistosomiasis (HSS). Propranolol is a non-selective beta-blocker used as secondary prophylaxis for UVB, but no previous studies have addressed carvedilol effects in rebleeding prevention.

Methods

A retrospective exploratory study of 57 patients with chronic HSS and index UVB treated with endoscopic variceal ligation and propranolol or carvedilol was conducted. The primary outcome was UVB-free time in the first 12 mo after the initial bleeding episode.

Results

Propranolol was used for secondary UVB prophylaxis in 43 (75.4%) participants (median dose 80 [interquartile range – IQR 60–80] mg/d) and carvedilol in 14 (24.6%) participants (median dose 12.5 [IQR 7.9–25.0] mg/d). During a 12-mo follow-up, rebleeding was observed in 13 (22.8%) patients, 9 (20.9%) of those treated with propranolol and 4 (28.6%) treated with carvedilol (p=0.715). Mean time from the beginning of drug prophylaxis to rebleeding was 6±3 mo and there was no difference between that for propranolol vs carvedilol subgroups. Portal vein thrombosis did not influence the bleeding recurrence in either subgroup.

Conclusion

Carvedilol may be equally effective as propranolol in preventing secondary UVB in HSS at 12-mo follow-up.

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.

Band ligation versus no intervention for primary prevention of upper gastrointestinal bleeding in adults with cirrhosis and oesophageal varices

BACKGROUND

The presence of oesophageal varices is associated with the risk of upper gastrointestinal bleeding. Endoscopic variceal ligation is used to prevent this occurrence but the ligation procedure may be associated with complications.

OBJECTIVES

To assess the beneficial and harmful effects of band ligation versus no intervention for primary prevention of upper gastrointestinal bleeding in adults with cirrhosis and oesophageal varices.

SEARCH METHODS

We combined searches in the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, and Science Citation Index with manual searches. The last search update was 9 February 2019.

SELECTION CRITERIA

We included randomised clinical trials comparing band ligation verus no intervention regardless of publication status, blinding, or language in the analyses of benefits and harms, and observational studies in the assessment of harms. Included participants had cirrhosis and oesophageal varices with no previous history of variceal bleeding.

DATA COLLECTION AND ANALYSIS

Three review authors extracted data independently. The primary outcome measures were all-cause mortality, upper gastrointestinal bleeding, and serious adverse events. We undertook meta-analyses and presented results using risk ratios (RRs) with 95% confidence intervals (CIs) and I² values as a marker of heterogeneity. In addition, we calculated the number needed to treat to benefit (NNTTB) for the primary outcomes . We assessed bias control using the Cochrane Hepato-Biliary domains; determined the certainty of the evidence using GRADE; and conducted sensitivity analyses including Trial Sequential Analysis.

MAIN RESULTS

Six randomised clinical trials involving 637 participants fulfilled our inclusion criteria. One of the trials included an additional small number of participants (< 10% of the total) with non-cirrhotic portal hypertension/portal vein block. We classified one trial as at low risk of bias for the outcome, mortality and high risk of bias for the remaining outcomes; the five remaining trials were at high risk of bias for all outcomes. We downgraded the evidence to moderate certainty due to the bias risk. We gathered data on all primary outcomes from all trials. Seventy-one of 320 participants allocated to band ligation compared to 129 of 317 participants allocated to no intervention died (RR 0.55, 95% CI 0.43 to 0.70; I² = 0%; NNTTB = 6 persons). In addition, band ligation was associated with reduced risks of upper gastrointestinal bleeding (RR 0.44, 95% CI 0.28 to 0.72; 6 trials, 637 participants; I² = 61%; NNTTB = 5 persons), serious adverse events (RR 0.55, 95% CI 0.43 to 0.70; 6 trials, 637 participants; I² = 44%; NNTTB = 4 persons), and variceal bleeding (RR 0.43, 95% CI 0.27 to 0.69; 6 trials, 637 participants; I² = 56%; NNTTB = 5 persons). The non-serious adverse events reported in association with band ligation included oesophageal ulceration, dysphagia, odynophagia, retrosternal and throat pain, heartburn, and fever, and in the one trial involving participants with either small or large varices, the incidence of non-serious side effects in the banding group was much higher in those with small varices, namely ulcers: small versus large varices 30.5% versus 8.7%; heartburn 39.2% versus 17.4%. No trials reported on health-related quality of life.Two trials did not receive support from pharmaceutical companies; the remaining four trials did not provide information on this issue.

AUTHORS' CONCLUSIONS

This review found moderate-certainty evidence that, in patients with cirrhosis, band ligation of oesophageal varices reduces mortality, upper gastrointestinal bleeding, variceal bleeding, and serious adverse events compared to no intervention. It is unlikely that further trials of band ligation versus no intervention would be considered ethical.

Use of nonselective β blockers after variceal eradication in cirrhotic patients undergoing secondary prophylaxis of esophageal variceal bleeding: a critical review of current evidence

Nonselective β blockers (NSBBs) combined with esophageal variceal ligation (EVL) are recommended for secondary prophylaxis of esophageal variceal bleeding (EVB) in cirrhotic patients according to the current practice guidelines and consensus. However, until now, there is a paucity of recommendations regarding the use of NSBBs in cirrhotic patients who achieved variceal eradication. In this review paper, we firstly introduced a case who achieved variceal eradication after additional use of NSBBs for secondary prophylaxis of EVB and then did not require further endoscopic therapy during repeated endoscopic surveillance, and subsequently discuss the importance of NSBBs for secondary prophylaxis of EVB, the effect of NSBBs after variceal eradication, adherence to NSBBs, screening for variceal recurrence, and timing of endoscopic surveillance after variceal eradication.

Carvedilol versus traditional, non-selective beta-blockers for adults with cirrhosis and gastroesophageal varices

BACKGROUND

Non-selective beta-blockers are recommended for the prevention of bleeding in people with cirrhosis, portal hypertension and gastroesophageal varices. Carvedilol is a non-selective beta-blocker with additional intrinsic alpha₁-blocking effects, which may be superior to traditional, non-selective beta-blockers in reducing portal pressure and, therefore, in reducing the risk of upper gastrointestinal bleeding.

OBJECTIVES

To assess the beneficial and harmful effects of carvedilol compared with traditional, non-selective beta-blockers for adults with cirrhosis and gastroesophageal varices.

SEARCH METHODS

We combined searches in the Cochrane Hepato-Biliary's Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, and Science Citation Index with manual searches. The last search update was 08 May 2018.

SELECTION CRITERIA

We included randomised clinical trials comparing carvedilol versus traditional, non-selective beta-blockers, irrespective of publication status, blinding, or language. We included trials evaluating both primary and secondary prevention of upper gastrointestinal bleeding in adults with cirrhosis and verified gastroesophageal varices.

DATA COLLECTION AND ANALYSIS

Three review authors (AZ, RJ and LH), independently extracted data. The primary outcome measures were mortality, upper gastrointestinal bleeding and serious adverse events. We undertook meta-analyses and presented results using risk ratios (RR) or mean differences (MD), both with 95% confidence intervals (CIs), and I² values as a marker of heterogeneity. We assessed bias control using the Cochrane Hepato-Biliary domains and the quality of the evidence with GRADE.

MAIN RESULTS

Eleven trials fulfilled our inclusion criteria. One trial did not report clinical outcomes. We included the remaining 10 randomised clinical trials, involving 810 participants with cirrhosis and oesophageal varices, in our analyses. The intervention comparisons were carvedilol versus propranolol (nine trials), or nadolol (one trial). Six trials were of short duration (mean 6 (range 1 to 12) weeks), while four were of longer duration (13.5 (6 to 30) months). Three trials evaluated primary prevention; three evaluated secondary prevention; while four evaluated both primary and secondary prevention. We classified all trials as at 'high risk of bias'. We gathered mortality data from seven trials involving 507 participants; no events occurred in four of these. Sixteen of 254 participants receiving carvedilol and 19 of 253 participants receiving propranolol or nadolol died (RR 0.86, 95% CI 0.48 to 1.53; I² = 0%, low-quality evidence). There appeared to be no differences between carvedilol versus traditional, non-selective beta-blockers and the risks of upper gastrointestinal bleeding (RR 0.77, 95% CI 0.43 to 1.37; 810 participants; 10 trials; I² = 45%, very low-quality evidence) and serious adverse events (RR 0.97, 95% CI 0.67 to 1.42; 810 participants; 10 trials; I² = 14%, low-quality evidence). Significantly more deaths, episodes of upper gastrointestinal bleeding and serious adverse events occurred in the long-term trials but there was not enough information to determine whether there were differences between carvedilol and traditional, non-selective beta-blockers, by trial duration. There was also insufficient information to detect differences in the effects of these interventions in trials evaluating primary or secondary prevention. There appeared to be no differences in the risk of non-serious adverse events between carvedilol versus its comparators (RR 0.55, 95% CI 0.23 to 1.29; 596 participants; 6 trials; I² = 88%; very low-quality evidence). Use of carvedilol was associated with a greater reduction in hepatic venous pressure gradient than traditional, non-selective beta-blockers both in absolute (MD -1.75 mmHg, 95% CI -2.60 to -0.89; 368 participants; 6 trials; I² = 0%; low-quality evidence) and percentage terms (MD -8.02%, 95% CI -11.49% to -4.55%; 368 participants; 6 trials; I² = 0%; low-quality evidence). However, we did not observe a concomitant reduction in the number of participants who failed to achieve a sufficient haemodynamic response (RR 0.76, 95% CI 0.57 to 1.02; 368 participants; 6 trials; I² = 42%; very low-quality evidence) or in clinical outcomes.

AUTHORS' CONCLUSIONS

We found no clear beneficial or harmful effects of carvedilol versus traditional, non-selective beta-blockers on mortality, upper gastrointestinal bleeding, serious or non-serious adverse events despite the fact that carvedilol was more effective at reducing the hepatic venous pressure gradient. However, the evidence was of low or very low quality, and hence the findings are uncertain. Additional evidence is required from adequately powered, long-term, double-blind, randomised clinical trials, which evaluate both clinical and haemodynamic outcomes.

Management of gastroesophageal varices in cirrhotic patients: current status and future directions

Bleeding from gastroesophageal varices (GEV) is a serious event in cirrhotic patients and can cause death. According to the explosion theory, progressive portal hypertension is the primary mechanism underlying variceal bleeding. There are two approaches for treating GEV: primary prophylaxis to manage bleeding or emergency treatment for bleeding followed by secondary prophylaxis. Treatment methods can be classified into two categories: 1) Those used to decrease portal pressure, such as medication (i.e., nonselective β-blockers), radiological intervention [transjugular intrahepatic portosystemic shunt (TIPS)] or a surgical approach (i.e., portacaval shunt), and 2) Those used to obstruct GEV, such as endoscopy [endoscopic variceal ligation (EVL), endoscopic injection sclerotherapy (EIS), and tissue adhesive injection] or radiological intervention [balloon-occluded retrograde transvenous obliteration (BRTO)]. Clinicians should choose a treatment method based on an understanding of its efficacy and limitations. Furthermore, elastography techniques and serum biomarkers are noninvasive methods for estimating portal pressure and may be helpful in managing GEV. The impact of these advances in cirrhosis therapy should be evaluated for their effectiveness in treating GEV.

Prevention and treatment of variceal haemorrhage in 2017

Variceal haemorrhage is a major complication of portal hypertension that still causes high mortality in patients with cirrhosis. Improved knowledge of the pathophysiology of portal hypertension has recently led to a more comprehensive approach to prevent all the complications of this condition. Thus, optimal treatment of portal hypertension requires a strategy that takes into account the clinical stage of the disease and all the major variables that affect the risk of progression to the next stage and death. In patients with compensated liver disease, the correction of factors influencing the progression of fibrosis, in particular aetiologic factors, is now feasible in many cases and should be achieved to prevent the development or progression of gastroesophageal varices and hepatic decompensation. Once gastroesophageal varices have developed, non-selective beta-blockers remain the cornerstone of therapy. Carvedilol provides a greater decrease in portal pressure and is currently indicated as a first-choice therapy for primary prophylaxis. The treatment of acute variceal haemorrhage includes a combination of vasoactive drugs, antibiotics and endoscopic variceal band ligation. In high-risk patients, the early use of transjugular intrahepatic portosystemic shunt (TIPS) lowers the risk of re-bleeding and improves survival. Transjugular intrahepatic portosystemic shunt is the choice for uncontrolled variceal bleeding; a self-expandable metal stent or balloon tamponade can be used as a bridging measure. The combination of non-selective beta-blockers and endoscopic variceal band ligation reduces the risk of recurrent variceal bleeding and improves survival. In these cases, statins seem to further improve survival. Transjugular intrahepatic portosystemic shunt is indicated in patients who rebleed during secondary prophylaxis.

Variceal Bleeding: Prophylaxis, Treatment, and Prevention

Variceal bleeding leads to significant morbidity and mortality in patients with portal hypertension. Mortality can be greater than 50% with the initial bleed and many patients develop recurrent bleeding with equal or greater mortality. Currently cirrhosis is the leading cause of portal hypertension, which is defined as a hepatic vein-portal vein gradient greater than 5 mmHg. Portal hypertension may arise from increased splanchnic blood flow due to systemic vasodilation that occurs in the hyperdynamic circulation of cirrhosis or from increased vascular resistance in intrahepatic and/or portocollateral vessels; by decreasing splanchnic blood flow, portal inflow decreases and so does portal pressure. Pharmacologic therapy consisting of nonselective β-blockers, vasopressin, and octreotide act by decreasing splanchnic blood flow, and long-acting nitrates may cause direct vasodilation of portocollateral vessels and/or decreased splanchnic blood flow. Nonselective β-blockers are the cornerstone of treatment for primary prophylaxis of bleeding, whereas vasopressin and octreotide are used for acute hemorrhaging. Two endoscopic modalities are available for control of acute bleeding and prevention of recurrent bleeding: sclerotherapy and endoscopic variceal ligation. After standard airway control and adequate fluid resuscitation, endoscopy helps localize the area of bleeding, and often in conjunction with vasopressin or octreotide can help control bleeding. Empiric antibiotics (fluoroquinolones or third-generation cephalosporins) should be started prior to endoscopy and early in the course of treatment. Sclerotherapy and band ligation along with nonselective β-blockers can help prevent recurrences of bleeding. For patients with bleeding gastric varices or uncontrollably bleeding esophageal varices, interventional radiologic procedures such as the transjugular intrahepatic portosystemic shunt (TIPS) can be used, and depending on the clinical condition and Child's classification of the patient, a surgically created portosystemic shunt may be appropriate treatment. Hopefully with emerging, new techniques and more widespread, prudent use of prophylactic drugs and endoscopy, the mortality and morbidity of variceal bleeding can be reduced.

Comparative portal hypotensive effects as propranolol of vitamin D₃ treatment by decreasing intrahepatic resistance in cirrhotic rats

BACKGROUND AND AIM

Vitamin D₃ improves portal hypertension (PH) through the activation of vitamin D receptor (VDR) and calcium-sensing receptor (CaSR) in cirrhotic rats. Propranolol is a non-selective β-blocker that is recommended for the treatment of PH. The present study aims to investigate the detail systemic and hepatic mechanisms of vitamin D₃ and propranolol, alone or in combination, in cirrhotic rats.

METHODS

Common bile duct-ligated and thioacetamide cirrhotic rats were treated with vehicle, propranolol (30 mg/kg/day), vitamin D₃ (0.5 μg/100 g/day, twice weekly), or propranolol + vitamin D₃, separately.

RESULTS

Significantly, propranolol and vitamin D₃ produced a similar magnitude of reduction in portal venous pressure (PVP) in cirrhotic rats through different mechanisms: whereas propranolol decreased PVP by reducing splanchnic hyperemia and cardiac index, vitamin D₃ decreased PVP by decreasing intrahepatic resistance (IHR). However, propranolol + vitamin D₃ did not further decrease PVP in cirrhotic rats. Notably, a marked decrease in hepatic VDR and CaSR expressions was noted in cirrhotic human/rat livers compared with non-cirrhotic human/rat livers. In cirrhotic rats, vitamin D₃ administration decreasing IHR by inhibiting the renin-angiotensin system, hepatic oxidative stress, inflammation/fibrosis, angiotensin II (ANGII) production, CaSR-mediated ANGII hyperresponsiveness, ANGII-induced hepatic stellate cells contraction, and correcting hepatic endothelial dysfunction through upregulation of hepatic VDR, CaSR, and endothelial nitric oxide synthase expressions.

CONCLUSION

Chronic vitamin D₃ treatment alone results in comparative portal hypotensive effects as propranolol alone in cirrhotic rats with PH. Taken together, chronic vitamin D₃ administration was an ideal alternative strategy to effectively improve PH without unwanted systemic side-effects.

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.

Randomized, controlled trial of carvedilol versus nadolol plus isosorbide mononitrate for the prevention of variceal rebleeding

BACKGROUND AND AIM

Carvedilol has been shown to be more effective than propranolol in decreasing portal pressure. Sufficient data from controlled trials remains limited. This trial compared the relative safety and efficacy between carvedilol and nadolol plus isosorbide mononitrate in preventing variceal rebleeding.

METHODS

After successful control of acute esophageal variceal bleeding, eligible patients were randomized to the carvedilol group, 61 patients, using carvedilol 6.25-12.5 mg daily or the N + I group, 60 patients, using nadolol 40-80 mg plus isorsorbide-5-mononitrate 20 mg daily. The end points were rebleeding from varices, adverse events or death.

RESULTS

After a median follow up of 30 months, recurrent upper gastrointestinal bleeding developed in 37 patients (61%) in the carvedilol group and 37 patients (62%) in the N + I group (P = 0.90). Recurrent bleeding from esophageal varices occurred in 31 patients (51%) in the carvedilol group and in 26 patients (43%) in the N + I group (P = 0.46). Recurrent bleeding from gastric varices occurred in two patients (3%) in the carvedilol group and in eight patients (13%) in the N + I group (P = 0.05). Severe adverse events occurred in one patient in the carvedilol group and 17 patients in the N + I group (P < 0.0001). Fifteen patients of the carvedilol group and 17 patients in the N + I group died (P = 0.83). Two patients in the carvedilol group and three patients in the N + I group died of variceal bleeding.

CONCLUSIONS

Carvedilol was as effective as nadolol plus isorsorbide-5 -mononitrate mononitrate in the prevention of gastroesophageal variceal rebleeding with fewer severe adverse events and similar survival.

The role of carvedilol in the management of portal hypertension

Carvedilol is a potent noncardioselective beta-blocker, with weak vasodilating properties because of alpha 1 blockade. A reduction in both intrahepatic and portocollateral resistance contribute to enhanced effects on portal pressure. There are 10 published hemodynamic studies involving 168 patients investigating the role of carvedilol in portal hypertension. A reduction in the hepatic venous pressure gradient of up to 43% (range 10-43%) has been reported, particularly after chronic administration. However, tolerability at doses greater than 12.5 mg/day was comprised because of a fall in mean arterial pressure (MAP), particularly in ascitic patients. Carvedilol was more effective than propranolol in reducing hepatic venous pressure gradient in two of three studies, albeit with a greater decrease in MAP. One study showed deterioration of pre-existing ascites with carvedilol. The addition of nitrates to propranolol was less effective than carvedilol monotherapy in another study. A large multicentre, randomized controlled trial comparing carvedilol with variceal band ligation for the prevention of variceal bleeding has been published. Carvedilol resulted in fewer episodes of bleeding, although there was no difference in survival. Carvedilol was well tolerated. Carvedilol is a promising agent, and seems to be more effective than propranolol in hemodynamic studies. The efficacy in primary prevention of variceal bleeding suggests that carvedilol has a role in the management of clinically significant portal hypertension.

Hepatoprotective effects of the nitric oxide donor isosorbide-5-mononitrate alone and in combination with the natural hepatoprotectant, silymarin, on carbon tetrachloride-induced hepatic injury in rats

The aim of this study was to investigate the effect of the nitric oxide donor isosorbide-5-mononitrate (5-ISMN) alone or in combination with the natural hepatoprotectant with anti-oxidant activity silymarin on the carbon tetrachloride (CCl(4))-induced hepatic injury in rats. 5-ISMN (1.8, 3.6 or 7.2 mg/kg), silymarin (25 mg/kg) or 5-ISMN (1.8, 3.6 or 7.2 mg/kg) combined with silymarin was given once daily orally simultaneously with CCl(4) and for 15 days thereafter. Liver damage was assessed by determining serum enzyme activities and hepatic histopathology. 5-ISMN given at the above doses conferred significant protection against the hepatotoxic actions of CCl(4) in rats, reducing serum alanine aminotransferase (ALT) levels by 31.2, 39.3 and 61.6%, respectively, when compared with controls. Serum aspartate aminotransferase (AST) levels decreased by 19.8, 22.7 and 59.4%, respectively, while alkaline phosphatase (ALP) decreased by 26.1 and 32.6% by the drug at 3.6 and 7.2 mg/kg, respectively. When silymarin was added to 5-ISMN (1.8, 3.6 or 7.2 mg/kg), ALT decreased by 32.8, 59.6, 70.2% and AST by 28.7, 50.3, 60%, when compared with CCl(4) control group levels. Silymarin in combination with 3.6 or 7.2 mg/kg 5-ISMN resulted in 37.5 and 39.2% reductions in ALP when compared with CCl(4) control group. Meanwhile, silymarin alone reduced ALT, AST and ALP levels by 65.9, 52 and 62.3%, respectively. Blood levels of reduced glutathione were markedly decreased in CCl(4)-treated rats. Reduced glutathione levels were increased by the administration of 5-ISMN and restored to near normal values by silymarin treatment. Histopathological alterations by CCl(4) were markedly reduced after treatment with 5-ISMN alone or in combination with silymarin. Histopathologic examination of the livers of CCl(4)-treated rats administered 5-ISMN at 7.2 mg/kg showed marked restoration of the normal architecture of the liver tissue and minimal fibrosis. Silymarin co-administered with 5-ISMN resulted in further improvement of the histologic picture. These results indicates that treatment with 5-ISMN protects against hepatocellular necrosis induced by CCl(4). The study suggests a potential therapeutic use for 5-ISMN in combination with silymarin in liver injury.

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.

Addition of propranolol and isosorbide mononitrate to endoscopic variceal ligation does not reduce variceal rebleeding incidence

BACKGROUND & AIMS

Endoscopic variceal ligation (EVL) and propranolol are standard secondary prophylaxis therapies for variceal bleeding. Addition of isosorbide mononitrate (ISMN) to propranolol improves its hemodynamic efficacy; we investigated whether a combination of EVL and propranolol/ISMN was more effective than EVL alone for secondary prophylaxis.

METHODS

Patients with a prior variceal bleed were randomly assigned to groups given a combination (n = 88) of EVL, propranolol (dose titrated to reduce heart rate to 55 beats per minute), and ISMN (40 mg/day) or EVL alone (n = 89). Primary end points were rebleeding or death; secondary end points were new complications of portal hypertension or serious adverse effects.

RESULTS

The actuarial probabilities of rebleeding 2 years after therapy were 27% in the combination group and 31% in the EVL alone group (P = .822). Two patients in the combination group and 3 patients in the EVL alone group died during the study period (P = .682); no deaths were caused by variceal hemorrhage. In cirrhotic patients, the actuarial probabilities of rebleeding were 24% and 30%, respectively (P = .720). Secondary end points were comparable between groups. In multivariate analyses, presence of ascites (P = .003), serum albumin < 3.3 g/dL (P = .008), and hepatic venous pressure gradients > or = 18 mm Hg (P = .009) were independent risk factors for variceal rebleeding.

CONCLUSIONS

EVL alone is sufficient to prevent variceal rebleeding in cirrhotic and noncirrhotic patients with history of variceal bleeding. Addition of propranolol and ISMN to EVL does not reduce the incidence of variceal rebleeding but increases severe adverse effects. Risk factors for rebleeding include ascites, low serum albumin, and high hepatic venous pressure gradients.

Early identification of haemodynamic response to pharmacotherapy is essential for primary prophylaxis of variceal bleeding in patients with 'high-risk' varices

BACKGROUND

A beta-blocker is recommended for primary prophylaxis of variceal bleeding; however, only one-third have hepatic venous pressure gradient (HVPG) response. The role of addition of isosorbide-5-mononitrate (ISMN) to beta-blocker and benefits of HVPG-guided 'a la carte' approach remain unclear.

AIM

To determine the benefits of HVPG-guided pharmacotherapy in primary prophylaxis of variceal bleeding using beta-blocker and ISMN.

PATIENTS AND METHODS

Consecutive patients of cirrhosis, with high-risk varices, with no previous variceal bleeding were included. After baseline HVPG, patients received incremental propranolol to achieve HR of 55/min. After one-month, HVPG was repeated to determine response (<12 mmHg or >or=20% reduction). ISMN was added in nonresponders and HVPG repeated. Patients were followed up for 24 months.

RESULTS

Of 56 patients (age 47 +/- 13, males 79%) from 89 eligible patients, 21 (38%) responded to beta-blocker alone. Six additional patients responded to combination. Thus, overall 48% (27/56) patients responded. Variceal bleeding occurred in seven of 56 (13%) patients [one of 27 (4%) responder, five of 23 (22%) nonresponders and one of six (17%) with unknown response; P = N.S.]. The actuarial probability of variceal bleeding at median 24 months was 4% in responders and 22% in nonresponders (P < 0.05). Ten (18%) patients developed adverse effects to propranolol and six of 35 (17%) to nitrates requiring dose reduction. Risk factors of variceal bleed were grade IV varices and haemodynamic nonresponse.

CONCLUSIONS

For primary prophylaxis, a beta-blocker is effective in 38% and addition of ISMN raises the response rate to about half of patients. The HVPG-guided 'a la carte' approach may be considered for these patients.

A randomized, controlled trial of banding ligation plus drug therapy versus drug therapy alone in the prevention of esophageal variceal rebleeding

BACKGROUND & AIMS

Both medications with beta-blockers and isosorbide-5-mononitrate and endoscopic variceal ligation have been proven plausible in the prevention of variceal rebleeding. However, the relative efficacy and safety of the combined treatment for preventing rebleeding remains unresolved.

METHODS

Patients with history of esophageal variceal bleeding were enrolled. Emergency ligation was performed in patients with acute variceal bleeding. After hemodynamic stability, eligible patients were randomized to either the Medication group, using nadolol plus isorsorbide-5-mononitrate, or the Combined group, receiving banding ligation in addition to medications. Patients in the two groups with rebleeding from esophageal varices were treated with band ligation. The end points were rebleeding from varices or death.

RESULTS

After a median follow up of 23 months, recurrent upper gastrointestinal bleeding developed in 51% in the Medication group and 38% in the Combined group (P = 0.21). Recurrent bleeding from esophageal varices occurred in 26 patients (43%) in the Medication group and in 16 patients (26%) in the Combined group (P = 0.07). Recurrent bleeding from gastroesophageal varices occurred in 48% of Medication group and 28% of Combined group (P = 0.05). The frequency of adverse effects and mortality rates were similar between both groups (P = 0.28).

CONCLUSIONS

Combined ligation with medications was marginally more effective than medication alone in the prevention of gastroesophageal variceal rebleeding with similar adverse effects and mortality.

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.

Improved survival in patients receiving medical therapy as compared with banding ligation for the prevention of esophageal variceal rebleeding

Both medical therapy and endoscopic variceal ligation (EVL) have proven to be comparable in the prevention of variceal rebleeding. However, the long-term results are still lacking. Our previous study enrolled 121 patients with history of esophageal variceal bleeding and randomized to receive EVL (EVL group, 60 patients) or drug therapy, nadolol plus isosorbide-5-mononitrate (N+I) (N+I group, 61 patients) to prevent variceal rebleeding. The EVL group received ligation regularly until variceal obliteration. The N+I group received N+I during the study period. Patients were followed for up to 8 years. After a median follow-up of 82 months, recurrent upper gastrointestinal bleeding developed in 28 patients (47%) in the EVL group and 49 patients (80%) in the N+I group (P = 0.001). Recurrent bleeding from esophageal varices occurred in 18 patients (30%) in the EVL group and 39 patients (64%) in the N+I group. The actuarial probability of rebleeding from esophageal varices was lower in the EVL group (P = 0.001). A total of 42 patients of the EVL group and 30 patients of the N+I group died (P = 0.013). The multivariate Cox analysis indicated that age, serum albumin, presence of encephalopathy, and treatment were the factors predictive of mortality.

CONCLUSION

Our long-term follow-up study showed that combination of N+I therapy was inferior to banding ligation in the reduction of variceal rebleeding, but with enhanced 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.

Variceal band ligation versus beta-blockers for primary prevention of variceal bleeding: a meta-analysis

BACKGROUND/AIMS

Variceal band ligation (VBL) can reduce the rate of the first variceal by 45-52% compared with beta-blockers (BBs). We performed an updated meta-analysis of nine randomized controlled trials published as full papers, comparing VBL with BB for primary prevention.

METHODS

Relative risk (RR) was computed using a random effects model. Sensitivity analysis was performed using a fixed effects model. Publication bias was also assessed using funnel plots and the rank correlation test.

RESULTS

In total, 734 patients were studied (356, VBL; 378, BB). The pooled RR favoured VBL for first variceal bleed [0.63; 95% confidence interval (CI), 0.43-0.92] with number needed to treat being 13 (95% CI, 7-33), and for adverse events resulting in treatment withdrawal (0.24; 95% CI, 0.12-0.47) with the corresponding number needed to treat being 10 (95% CI, 6-25). Banding-related bleeding occurred in six patients (fatal in two). No difference was seen in bleeding-related deaths (RR, 0.71; 95% CI, 0.38-1.32), or overall mortality (RR, 1.09; 95% CI, 0.86-1.38). No significant heterogeneity or publication bias was present, and outcomes remained robust after sensitivity analyses.

CONCLUSIONS

VBL was superior to BB in preventing the first variceal bleed, with fewer adverse events resulting in treatment discontinuation. Careful attention to technique and patient selection are important to minimize iatrogenic complications with VBL. VBL has a role in patients with poor drug compliance, or tolerance, and in those who bleed on BB therapy.

The future treatment of portal hypertension

Increased understanding of the hyperdynamic circulation syndrome has resulted in novel therapeutic approaches, some of which have already reached clinical practice. Central to the hyperdynamic circulation syndrome is an imbalance between the increase in different vasodilators (foremost among which is nitric oxide) and the compensatory increase in vasoconstrictors--usually accompanied by a blunted response. This chapter discusses the role of endothelin in the pathogenesis of the syndrome and in future treatment approaches. A relatively new area of research in this field is the role of infection and inflammation in the initiation and maintenance of the hyperdynamic circulation syndrome. The use of antibiotics in the setting of acute variceal bleeding is standard practice. Studies have suggested that chronic manipulation of the intestinal flora could have beneficial effects in the treatment of portal hypertension. The bile salts are another novel and interesting target. Although their vasoactive properties have been known for some time, recent data demonstrate that their effects could be central in the pathogenesis of the hyperdynamic circulation syndrome, and that manipulation of the composition of the bile acid pool could be a therapeutic approach to portal hypertension. Finally, hypoxia and angiogenesis play a role in the development of portal hypertension and the formation of collaterals. This role needs to be further defined but it appears likely that this phenomenon is yet another target for therapeutic intervention.

A novel transdermal patch incorporating isosorbide dinitrate with bisoprolol: in vitro and in vivo characterization

The combination therapy of nitrate and selective beta-adrenoceptor antagonist has shown benefits for treatment of hypertension and heart disease than either drug alone. The objectives of the present study were to define effects on the anti-hypertension activity and pharmacokinetics of a novel transdermal patch incorporating isosorbide dinitrate (ISDN) with bisoprolol (BP). The 3:2 ratio of ISDN to BP (mg/mg) in the transdermal patches exhibited better anti-hypertension effect synergistically with a similar inhibiting heart rates effect to that of BP alone in renovascular hypertensive rats, and was therefore selected as a final formulation. The in vitro transdermal penetration of both ISDN and BP from the patches displayed a zero-order process, and the penetration rate constants were 7.4 microg/(cm(2)h) for ISDN, and 5.9 microg/(cm(2)h) for BP, respectively. After transdermal administration at single dose or multiple doses, the synergistic anti-hypertension effect was confirmed in spontaneously hypertensive rats also. The effect of each patch lasts for 3 days, and increased with the total dose of two drugs (2mg/cm(2), ISDN:BP=3:2, mg/mg), showing a dose dependant manner. After transdermal administration to rabbits, the absolute bioavailabilities were 33.6% for ISDN, and 31.3% for BP, respectively. The maximal concentrations (C(max)) of both drugs were significantly reduced while the areas under the plasma concentration-time curve (AUC), and mean residence times (MRT) were evidently increased and extended, respectively. As a patient-friendly, convenient, and multi-day dosing therapeutic system, the transdermal patches incorporating ISDN and BP could be promising for prevention and treatment of hypertension.

Prevention of esophageal variceal rebleeding

The rate of rebleeding of esophageal varices remains high after cessation of acute esophageal variceal hemorrhage. Many measures have been developed to prevent the occurrence of rebleeding. When considering their effectiveness in reduction of rebleeding, the associated complications cannot be neglected. Due to unavoidable high incidence of complications, shunt surgery and endoscopic injection sclerotherapy are now rarely used. Transjugular intrahepatic portosystemic stent shunt was developed to replace shunt operation but is now reserved for rescue therapy. Nonselective beta-blockers alone or in combination with isosorbide mononitrate and endoscopic variceal ligation are currently the first choices in the prevention of variceal rebleeding. The combination of nonselective beta-blockers and endoscopic variceal ligation appear to enhance the efficacy. With the advent of newly developed measures, esophageal variceal rebleeding could be greatly reduced and the survival of cirrhotics with bleeding esophageal varices could thereby be prolonged.

Transjugular intrahepatic portosystemic shunt in the prevention of rebleeding in oesophageal varices

Variceal bleeding is a common complication of cirrhosis and has a high in-patient mortality (30-50%). Rebleeding is a major cause of death and occurs in 35% of patients at 6 weeks after the initial bleeding episode and 75% at 1 year. Therefore, strategies that improve survival by preventing rebleeding in the early period are crucial to improve long-term survival. This review concentrates on the evidence for transjugular intrahepatic portosystemic shunt in the prevention of rebleeding. Transjugular intrahepatic portosystemic shunt in comparison with endoscopic and pharmacological therapies is clearly superior at reducing the rate of rebleeding in those patients who had an oesophageal variceal haemorrhage. It, however, does not improve mortality and is associated with a greater risk of encephalopathy and is more costly than endoscopic procedures. It is therefore generally used when endoscopic therapy has failed but may be useful in patients who would tolerate a rebleed poorly such as Child's C patients. Randomized-controlled trials are required to evaluate the role of polytetrafluoroethylene shunts in the prevention of rebleeding as their improved patency and suggested reduced incidence of encephalopathy make them a very attractive potential treatment for rebleeding.

Dental management of patients with end-stage liver disease

This article presents a review of end-stage chronic liver disease (cirrhosis) with emphasis on the clinical presentation, diagnosis, and complications of cirrhosis, along with their medical and surgical management and prognosis. This article also discusses the evaluation and management of the dental patients with cirrhosis, including the implications decreased hepatic function has on drugs commonly used in dental treatment.

Comparative study between nadolol and 5-isosorbide mononitrate vs. endoscopic band ligation plus sclerotherapy in the prevention of variceal rebleeding in cirrhotic patients: a randomized controlled trial

BACKGROUND

After variceal bleeding, cirrhotic patients should receive secondary prophylaxis.

AIM

To compare nadolol plus 5-isosorbide mononitrate (5-ISMN) with endoscopic band ligation. The end points were rebleeding, treatment failure and death.

METHODS

One hundred and nine cirrhotic patients with a recent variceal bleeding were randomized: nadolol plus 5-ISMN in 57 patients and endoscopic band ligation in 52 patients.

RESULTS

The mean follow-up was 17 and 19 months in nadolol plus 5-ISMN and endoscopic band ligation groups, respectively. No differences were observed between groups in upper rebleeding (47% vs. 46%), variceal rebleeding (40% vs. 36%), failure (32% vs. 22%), major complications (7% vs. 13.5%) and death (19% vs. 20%), respectively. The actuarial probability of remaining free of rebleeding, failure and deaths were similar in both groups. Time to rebleeding shows that endoscopic band ligation patients had an early rebleed, with a median of 0.5 month (95% CI: 0.0-4.2) compared with patients from nadolol plus 5-ISMN, 7.6 months (95% CI: 2.9-12.3, P < 0.013). Multivariate analysis indicated that outcome-specific predictive factor(s) for rebleeding was Child A vs. B + C (P < 0.01); for failure was Child A vs. B + C (P < 0.02); and for death ascites (P < 0.01) and rebleeding (P < 0.02).

CONCLUSION

This trial suggests no superiority of endoscopic band ligation over nadolol plus 5-ISMN mononitrate for the prevention of rebleeding in cirrhotic patients.

Pharmacologic therapy of portal hypertension

Portal hypertension is a progressively debilitating complication of cirrhosis and a principal cause of mortality in patients who have hepatic decompensation. During the last few decades, significant clinical advances in the prevention of initial variceal hemorrhage, the management of acute variceal hemorrhage, and the prevention of recurrent variceal hemorrhage have reduced the morbidity and mortality of this lethal complication of cirrhosis. This article discusses the pharmacologic treatment of portal hypertension, including preprimary prophylaxis, prevention of a first variceal hemorrhage, treatment of acute variceal hemorrhage, and secondary prophylaxis of a variceal hemorrhage.

Current management of the complications of portal hypertension: variceal bleeding and ascites

Portal hypertension is one of the main consequences of cirrhosis. It results from a combination of increased intrahepatic vascular resistance and increased blood flow through the portal venous system. The condition leads to the formation of portosystemic collateral veins. Esophagogastric varices have the greatest clinical impact, with a risk of bleeding as high as 30% within 2 years of medium or large varices developing. Ascites, another important complication of advanced cirrhosis and severe portal hypertension, is sometimes refractory to treatment and is complicated by spontaneous bacterial peritonitis and hepatorenal syndrome. We describe the pathophysiology of portal hypertension and the current management of its complications, with emphasis on the prophylaxis and treatment of variceal bleeding and ascites.

Non-invasive diagnosis of large oesophageal varices with FibroTest in patients with cirrhosis: a preliminary retrospective study

BACKGROUND AND AIMS

Primary prevention of variceal bleeding with beta-blockers improves survival in patients with large oesophageal varices (LOV). Therefore, cirrhotic patients frequently undergo screening endoscopy. As portal hypertension is related to liver fibrosis, this study aimed to assess the predictive value of FibroTest, a non-invasive marker of liver fibrosis, for the diagnosis of LOV in cirrhotic patients.

METHODS

Ninety-nine cirrhotic patients had clinical examination, blood sample (liver function tests, platelet count, FibroTest) and upper endoscopy. Measurements of endoscopic and biochemical parameters were made blindly. Sensitivity, specificity, predictive values and area under the receiver operating characteristic curves were assessed for FibroTest, platelet count and Child-Pugh score. The main endpoint was the presence of LOV.

RESULTS

Platelet count, prothrombin time, ascites, FibroTest and Child-Pugh class were significantly different among patients with or without LOV. FibroTest had the highest discriminative power with an area under receiver operating characteristics curves of 0.77 (SE=0.06), compared with 0.64 (0.08) and 0.68 (0.08) for platelet count and Child-Pugh score, respectively (P=0.08). A cut-off at 0.80 had a 86% negative predictive value for the diagnosis of LOV (Se=92%, Sp=21%).

CONCLUSION

FibroTest could aid in the diagnosis of LOV and may therefore reduce the indication of endoscopic screening in cirrhotic patients.

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.

Effect of vardenafil, an inhibitor of phosphodiesterase-5, on portal haemodynamics in normal and cirrhotic liver -- results of a pilot study

BACKGROUND

Dysregulation of the cyclic guanosine 3',5' monophosphate-nitric oxide system is in part responsible for portal hypertension in cirrhosis.

AIM

To test the effects of inhibitors of phosphodiesterase-5 on portal haemodynamics.

METHODS

To 18 healthy subjects and 18 patients with Child A liver cirrhosis, 10 mg of vardenafil, an inhibitor of phosphodiesterase-5, were administered orally. Doppler sonographic measurements of hepatic and splanchnic blood flow, systemic blood pressure and heart rate were recorded before, 1 h after, and 48 h after the application. Vardenafil plasma levels were determined after 1 h. In five patients, invasive registration of free and wedged hepatic vein pressure was performed.

RESULTS

Portal venous flow increased in patients from 0.82 +/- 0.30 L/min (mean +/- s.d.) by 26% (CI: 16-37%, P = 0.0004) and in healthy subjects from 0.75 +/- 0.20 L/min (mean +/- s.d.) by 19% (CI: 9-28%; P = 0.0010). Celiac and hepatic artery resistivity indices rose significantly. Systemic blood pressure decreased slightly in patients. The wedged hepatic venous pressure gradient decreased in four of five patients with liver cirrhosis. Vardenafil plasma levels were higher in patients (14 +/- 10 microg/L) than in healthy subjects (9 +/- 6 microg/L; n.s.).

CONCLUSIONS

Inhibition of phosphodiesterase-5 increases portal flow and lowers portal pressure by a decrease in sinusoidal resistance and may be a novel therapeutic strategy for portal hypertension.

Endoscopic band ligation in the treatment of portal hypertension

The evidence that endoscopic band ligation (EBL) has greater efficacy and fewer side effects than endoscopic injection sclerotherapy has renewed interest in endoscopic treatments for portal hypertension. The introduction of multishot band devices, which allow the placement of 5-10 bands at a time, has made the technique much easier to perform, avoiding the use of overtubes and their related complications. EBL sessions are usually repeated at 2 week intervals until varices are obliterated, which is achieved in about 90% of patients after 2-4 sessions. Variceal recurrence is frequent, with 20-75% of patients requiring repeated EBL sessions. According to current evidence, nonselective beta-blockers are the preferred treatment option for prevention of a first variceal bleed, whereas EBL should be reserved for patients with contraindications or intolerance to beta-blockers. Nonselective beta-blockers, probably in association with the vasodilator isosorbide mononitrate, and EBL are good treatment options to prevent recurrent variceal rebleeding. The efficacy of EBL might be increased by combining it with beta-blocker therapy. Patients who are intolerant, have contraindications or bled while receiving primary prophylaxis with beta-blockers must be treated with EBL. In the latter situation, EBL should be added to rather than replace beta-blocker therapy. EBL, in combination with vasoactive drugs, is the recommended form of therapy for acute esophageal variceal bleeding; however, endoscopic injection sclerotherapy can be used in the acute setting if EBL is technically difficult.

Modern management of portal hypertension

The development of portal hypertension plays a major role in the pathogenesis of many of the complications of chronic liver disease. In developed countries, most patients with portal hypertension have cirrhosis, and, in this condition, portal pressure is elevated as a result of both an increase in hepatic resistance to portal perfusion and increased mesenteric blood flow. Bleeding from oesophageal varices is a major cause of mortality in patients with significant portal hypertension. This review concentrates on the recognition, prevention and acute management of this life threatening complication of cirrhosis.

Beta blocker prophylaxis for patients with variceal hemorrhage

GOALS

To characterize beta blocker therapy for the primary and secondary prevention of variceal hemorrhage.

BACKGROUND

Variceal hemorrhage is one of the more frequent and severe complications of portal hypertension due to liver disease. Beta blocker therapy has been demonstrated to decrease risk of first bleed in patients with evidence of varices and recurrent bleeding and mortality in patients with history of prior variceal hemorrhage.

STUDY

A total of 106 patients with liver disease hospitalized with suspected variceal hemorrhage were retrospectively reviewed.

RESULTS

Half of patients had known varices, 44 (41.5%) of whom had experienced prior variceal hemorrhage. Only 21 (20%) were receiving beta blocker therapy at admission and 41 (48%) at discharge. The majority were not receiving therapy for primary prophylaxis (94%). Specific characteristics associated with beta blocker use could not be identified, although more patients with history of greater than two variceal hemorrhages were receiving beta blocker at admission (73% vs. 41%, P = 0.04)

CONCLUSIONS

This study suggests that liver disease patients with varices are often not receiving beta blocker therapy to reduce risk of first or subsequent variceal hemorrhage. Opportunity exists to optimize use of this proven prophylactic treatment and bridge an apparent gap in standard of care.

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.

Diagnosis and treatment of portal hypertension

Prevention of the first variceal haemorrhage should start when the patients have developed medium-sized to large varices. Non-selective beta-blockers and band ligation are equally effective in preventing the first bleeding episode. Rubber band ligation is the first choice for patients with contraindications or intolerance to beta-blockers. Treatment of acute bleeding should aim at controlling bleeding and preventing early rebleeding and complications, especially infections. Combined endoscopic (band ligation or sclerotherapy) and pharmacological treatment with vasoactive drugs can control bleeding in up to 90% of patients. Antibiotic prophylaxis is an integral part of the treatment of acute variceal haemorrhage, and must be started as soon as possible. Emergency transjugular intrahepatic portosystemic stent shunt (TIPS) is the standard rescue therapy for patients failing combined endoscopic and pharmacological treatment. All patients who survive a variceal bleed should be treated with beta-blockers or band ligation to prevent rebleeding. All patients in whom bleeding cannot be controlled or who continue to rebleed can be treated with salvage TIPS or, in selected cases, with surgical shunts. Liver transplantation should be considered for patients with severe liver insufficiency in which first-line treatments fail.

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.

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.

Portal hypertensive bleeding

Portal hypertension bleeding is a common and serious complication of cirrhosis. All patients with cirrhosis should undergo endoscopy and be evaluated for possible causes of current or future portal hypertensive bleeding. Possible causes of bleeding include esophageal varices, gastric varices, and PHG. Patients with esophageal varices at high risk of bleeding should be treated with nonselective beta-blockers for primary prevention of variceal hemorrhage. HVPG measurements represent the optimal way to monitor the success of pharmacologic therapy. EVL may be used in those with high-risk varices who do not tolerate beta-blockers. When active bleeding develops, simultaneous and coordinated attention must be given to hemodynamic resuscitation, prevention and treatment of complications, and active control of bleeding. In cases of acute esophageal variceal (Fig. 5) and PHG bleeding, terlipressin, somatostatin, or octreotide should be started. Endoscopic treatment is provided for those with bleeding esophageal varices. If first-line therapy fails, TIPS or surgery may need to be performed. Unlike esophageal variceal or PHG bleeding, there is no established optimal treatment for gastric variceal bleeding. Individual and specific treatment modalities for acute gastric variceal bleeding must be calculated carefully after considering side effects.

Propranolol plus placebo versus propranolol plus isosorbide-5-mononitrate in the prevention of a first variceal bleed: a double-blind RCT

Nonselective beta-blockers are very effective in preventing first variceal bleeding in patients with cirrhosis. Treatment with isosorbide-5-mononitrate (IS-MN) plus propranolol achieves a greater reduction in portal pressure than propranolol alone. The present multicenter, prospective, double-blind, randomized, controlled trial evaluated whether combined drug therapy could be more effective than propranolol alone in preventing variceal bleeding. A total of 349 consecutive cirrhotic patients with gastroesophageal varices were randomized to receive propranolol + placebo (n = 174) or propranolol + IS-MN (n = 175). There were no significant differences in the 1- and 2-year actuarial probability of variceal bleeding between the 2 groups (propranolol + placebo, 8.3% and 10.6%; propranolol + IS-MN, 5% and 12.5%). The only independent predictor of variceal bleeding was a variceal size greater than 5 mm. However, among patients with varices greater than 5 mm (n = 196), there were no significant differences in the incidence of variceal bleeding between the 2 groups. Survival was also similar. Adverse effects were significantly more frequent in the propranolol + IS-MN group due to a greater incidence of headache. There were no significant differences in the incidence of new-onset or worsening ascites or in impairment of renal function. In conclusion, propranolol effectively prevents variceal bleeding. Adding IS-MN does not further decrease the low residual risk of bleeding in patients receiving propranolol. However, the long-term use of this combination drug therapy is safe and may be an alternative in clinical conditions associated with a greater risk of bleeding.