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Portopulmonary hypertension (PPH) is the coexistence of pulmonary arterial hypertension (PAH) and portal hypertension in patients with or without cirrhosis. PAH may develop in 2-6% of patients with portal hypertension and is the result of complex pathophysiological interactions between the portal and pulmonary circulations. The pathogenic mechanisms are unknown and depend both on the underlying severity of the liver disease and on the adaptation of the heart to the disease of the pulmonary vessels. Various pathophysiological aspects appear to be involved in the development of PPH, including angiogenesis, genetics, humoral changes, and inflammation with increased pulmonary phagocytosis. Female gender and estrogen metabolism with elevated estrogen levels are associated with the development of PPH. Of particular interest is the activation of powerful local vasoconstrictor systems, the imbalance between vasoconstrictors and vasodilators, which contributes to the narrowing of pulmonary vessels. Increased pulmonary blood flow causing shear stress can lead to endothelial damage and dysfunction with vasoconstriction and progressive vascular remodeling. However, only a small number of patients develop PPH, which indicates the involvement of other factors. Therefore, other numerous theories have been proposed that require further study. [ABSTRACT FROM AUTHOR]

Liver diseases affect the heart and the vascular system. Cardiovascular complications appear to be a leading cause of death in patients with non-alcoholic fatty liver disease (NAFLD) and cirrhosis. The predominant histological changes in the liver range from steatosis to fibrosis to cirrhosis, which can each affect the cardiovascular system differently. Patients with cirrhotic cardiomyopathy (CCM) and NAFLD are at increased risk of impaired systolic and diastolic dysfunction and for suffering major cardiovascular events. However, the pathophysiological mechanisms behind these risks differ depending on the nature of the liver disease. Accurate assessment of symptoms by contemporary diagnostic modalities is essential for identifying patients at risk, for evaluating candidates for treatment, and prior to any invasive procedures. This review explores current perspectives within this field. [ABSTRACT FROM AUTHOR]

Background: Hyperdynamic circulation in portal hypertension (PHT) depends on central neural activation. However, the initiating mechanism that signals PHT to the central neural cardiovascular-regulatory centers remains unclear. We aimed to test the hypothesis that oxidative stress in the gut initiates the signal that activates central cardiovascular nuclei in portal hypertensive rats. Methods: Two groups of rats were used. One had portal hypertension produced by partial portal vein ligation, while controls underwent sham operation. Hemodynamics including portal pressure, cardiac output, mean arterial pressure (MAP) and peripheral vascular resistance were measured. Activation of central cardiovascular nuclei was determined by immunohistochemical Fos expression in the paraventricular nucleus (PVN) of the hypothalamus. Myeloperoxidase activity, an oxidative stress marker, was measured in the jejunum. Hydrogen peroxide, the antioxidant N-acetyl-cysteine (NAC) or saline controls were administered for 12–14 days by gavage or osmotic minipumps placed in the peritoneal cavity. Results: Compared with controls, PHT rats showed increased cardiac output (54.2 ± 9.5 vs 33.6 ± 2.4 ml/min/100 g BW, p < 0.01), decreased MAP (96.2 ± 6.4 mmHg vs 103.2 ± 7.8, p < 0.01) and systemic vascular resistance (1.84 ± 0.28 vs 3.14 ± 0.19 mmHg/min/ml/100 g BW, p < 0.01). PHT rats had increased jejunal myeloperoxidase and PVN Fos expression. NAC treatment eliminated the hyperdynamic circulation, decreased jejunal myeloperoxidase and PVN Fos expression in PHT rats, but had no effect on sham controls. H2O2 significantly increased PVN Fos expression and decreased MAP. Conclusion: These results indicate that in PHT, mesenteric oxidative stress is the initial signal that activates chemoreceptors and triggers hyperdynamic circulation by central neural cardiovascular-regulatory centers. [ABSTRACT FROM AUTHOR]

Portal hypertension exacerbates the disease course of cirrhosis and is responsible for major complications, including bleeding from esophageal varices, ascites, and encephalopathy. More than 40 years ago, Lebrec and colleagues introduced beta-blockers to prevent esophageal bleeding. However, evidence now suggests that beta-blockers may cause adverse reactions in patients with advanced cirrhosis. This review addresses current evidence for the pathophysiology of portal hypertension, focusing on the pharmacological effects of treatment with beta-blockers, indications for preventing variceal bleeding, their effects on decompensated cirrhosis, and the risk of treating patients suffering from decompensated ascites and renal dysfunction with beta-blockers. The diagnosis of portal hypertension should be based on direct measurements of portal pressure. Carvedilol or nonselective beta-blockers are the first-line treatment for patients with medium-to-large varices as primary or secondary prophylaxis, in Child C patients with small varices, and sometimes for patients with clinically significant portal hypertension (HVPG ≥ 10 mm Hg, irrespective of the presence of varices) to prevent decompensation. Caution should be used when treating decompensated patients who are suspected of imminent cardiac and renal dysfunction. Future strategies for managing patients with portal hypertension should aim for more personalized treatment that takes into account the disease stage. [ABSTRACT FROM AUTHOR]

Objective: To identify patients with occult cardiac dysfunction and its relationship with the severity of liver impairment. Method: This is a Judgment (Purposive) Sampling, cross-sectional study that was conducted at Kafrelsheikh University Hospital, Egypt, from November 2019 to December 2020, and comprised adult patients of either gender with liver cirrhosis. After detailed history, a clinical examination, pathological assessment and cardiac evaluation based on electrocardiogram and echocardiography, the patients were divided into three groups. Patients who had dyspnoea or cyanosis were in group A, those who did not have dyspnoea or cyanosis but had electrocardiogram and echocardiography abnormalities were in group B, and patients who did not have dyspnoea, cyanosis or electrocardiogram and echocardiography abnormalities were in group C. The severity of the liver disease was evaluated using Child-Pugh and Model of End Liver Disease scores. Data was analysed using SPSS 20. Results: Of the 300 patients, 153(51%) were males and 147(49%) were females. The overall mean age was 55.1±5.1 years (range: 20-60 years). There were 58(19.33%) patients in group A, 108(36%) in group B and 134(44.66%) in group C. Group A patients showed higher Child-Pugh and Model of End Liver Disease scores than the other groups (p6 and Model of End Liver Disease score >37 yielded the best accuracy for detecting cardiac abnormalities in group B (p

Background: In cirrhosis, cardiac systolic dysfunction as part of cirrhotic cardiomyopathy affects prognosis. Myocardial mechano‐energetic efficiency (MEE) is an estimate of left ventricular performance. In this study we investigated the relation of MEE to patient characteristics and its impact on survival in patients with cirrhosis. Patients and Methods: We included 283 patients with cirrhosis of different severity according to the Child−Pugh classifications (A/B/C: 106/87/90). All patients had a liver vein catheterization and a hemodynamic investigation performed including determination of cardiac output (CO), stroke volume and heart rate (HR). These data were used to assess MEE, which was defined as (stroke volume/HR) × 1.666. Results: Eighty‐nine percent of patients had portal hypertension (hepatic venous pressure gradient >5 mmHg) and 80% indications of hyperdynamic circulatory state (increased CO and HR). There was no difference in MEE in Child−Pugh class C patients (2.03) versus Child−Pugh class A (1.98) and B (2.05) patients. In Child−Pugh class C patients, low MEE was associated with a poorer prognosis. Conclusion: In our study, MEE does not seem to be associated with severity of the liver disease, but in patients with advanced disease low MEE is associated with a poorer prognosis. The prognostic impact of MEE should be further investigated. [ABSTRACT FROM AUTHOR]

The radial artery is commonly used as the site measuring pulse pressure variation (PPV) during surgery. Accurate measurement of circulating blood volume and timely interventions to maintain optimal circulating blood volume is important to deliver sufficient oxygen to tissues and organs. It has not rather than never studied in patients undergoing liver transplantation whether PPV measured at peripheral sites, such as the radial artery, do represent central PPV for evaluating blood volume. In this retrospective study, 51 liver transplant recipients were enrolled. The two PPVs had been automatically recorded every minute in electrical medical records. A total 1878 pairs of the two PPVs were collected. The interchangeability of PPV measured at the radial and the femoral artery was analyzed by using the Bland–Altman plot, four-quadrant plot, Cohen's kappa (k), and receiver operating curve. The bias and limits of agreement of the two PPVs were −1.3% and −8.8% to 6.2%, respectively. The percentage error was 75%. The concordance rate was 65%. The Kappa of PPV-radial determining whether PPV-femoral was >13% or ≤13% was 0.64. We found that PPV-radial is not interchangeable with PPV-femoral during liver transplantation. Additionally, PPV-radial failed to reliably track changes of PPV-femoral. Lastly, the clinical decision regarding blood volume status (depletion or not) is significantly different between the two PPVs. Therefore, PPV-femoral may help maintain blood volume circulating to major organs including the newly transplanted liver graft for liver transplant recipients. [ABSTRACT FROM AUTHOR]

Background: Liver cirrhosis is characterized by liver fibrosis and pathological angiogenesis, which results in hyperdynamic circulation, portal-systemic collateral vascular formation, and abnormal angiogenesis. Lycopene is a nutrient mostly found in tomatoes. The beneficial effects of lycopene include anti-inflammation, anti-oxidation, anti-fibrosis, and anti-angiogenesis; however, the association between liver cirrhosis and pathological angiogenesis has yet to be studied. This study aimed to investigate the effects of lycopene on biliary cirrhotic rats. Methods: The efficacy of lycopene treatment in common bile duct ligation (BDL)-induced biliary cirrhotic rats was evaluated. Sham-operated rats served as surgical controls. Lycopene (20 mg/kg/day, oral gavage) or vehicle was administered to BDL or sham-operated rats for 4 weeks, after which the hemodynamics, liver biochemistry, portal-systemic shunting, liver and mesenteric angiogenesis, and hepatic angiogenesis-related protein expressions were examined. Results: Lycopene alleviated hyperdynamic circulation as evidenced by decreased cardiac index and increased peripheral vascular resistance (p < 0.05), but it did not affect portal pressure or liver biochemistry in the BDL rats (p > 0.05). Lycopene significantly diminished the shunting degree of portal-systemic collaterals (p = 0.04) and mesenteric vascular density (p = 0.01), and also ameliorated intrahepatic angiogenesis and liver fibrosis. In addition, lycopene upregulated endothelial nitric oxide synthase, protein kinase B (Akt) and phosphatidylinositol 3-kinases (PI3K), and downregulated vascular endothelial growth factor receptor 2 (VEGFR-2) protein expressions (p < 0.05) in the livers of the BDL rats. Conclusion: Lycopene ameliorated liver fibrosis, hyperdynamic circulation, and pathological angiogenesis in biliary cirrhotic rats, possibly through the modulation of intrahepatic Akt/PI3K/eNOS and VEGFR-2 pathways. [ABSTRACT FROM AUTHOR]

Background and aims: The cardiovascular hormones renin/angiotensin/aldosterone (RAA), brain-type natriuretic peptide (BNP)and arginine-vasopressin (AVP) are key regulators of systemic circulatory homeostasis in portal hypertension (PH). We assessed (i) the activation of renin, BNP and AVP across distinct stages of PH and (ii) whether activation of these hormones correlates with clinical outcomes. Methods: Plasma levels of renin, proBNP and copeptin (AVP biomarker) were determined in 663 patients with advanced chronic liver disease (ACLD) undergoing hepatic venous pressure gradient (HVPG) measurement at the Vienna General Hospital between 11/2011 and 02/2019. We stratified for Child stage (A–C), HVPG (6–9 mmHg, 10–15 mmHg, ≥ 16 mmHg) and compensated vs. decompensated ACLD. Results: With increasing PH, hyperdynamic state was indicated by higher heart rates (6–9 mmHg: median 71.0 [IQR 18.0] bpm, 10–15 mmHg: 76.0 [19.0] bpm, ≥ 16 mmHg: 80.0 [22.0] bpm; p < 0.001), lower mean arterial pressure (6–9 mmHg: 103.0 [13.5] mmHg, 10–15 mmHg: 101.0 [19.5] mmHg, ≥ 16 mmHg: 99.0 [21.0] mmHg; p = 0.032) and lower serum sodium (6–9 mmHg: 139.0 [3.0] mmol/L, 10–15 mmHg: 138.0 [4.0] mmol/L, ≥ 16 mmHg: 138.0 [5.0] mmol/L; p < 0.001). Across HVPG strata (6–9 mmHg vs. 10–15 mmHg vs ≥ 16 mmHg), median plasma levels of renin (21.0 [50.5] vs. 25.1 [70.9] vs. 65.4 [219.6] µIU/mL; p < 0.001), proBNP (86.1 [134.0] vs. 63.6 [118.0], vs. 132.2 [208.9] pg/mL; p = 0.002) and copeptin (7.8 [7.7] vs. 5.6 [8.0] vs. 10.7 [18.6] pmol/L; p = 0.024) increased with severity of PH. Elevated renin levels independently predicted first hepatic decompensation (adjusted hazard ratio [aHR]: 1.69; 95% confidence interval [95% CI] 1.07–2.68; p = 0.025) and mortality in compensated patients (aHR: 3.15; 95% CI 1.70–5.84; p < 0.001) and the overall cohort aHR: 1.42; 95% CI 1.01–2.01; p = 0.046). Elevated copeptin levels predicted mortality in decompensated patients (aHR: 5.77; 95% CI 1.27–26.33; p = 0.024) and in the overall cohort (aHR: 3.29; 95% CI 1.36–7.95; p = 0.008). ProBNP levels did not predict clinical outcomes. Conclusions: The cardiovascular hormones renin, proBNP and AVP are activated with progression of ACLD and PH. Renin activation is a risk factor for hepatic decompensation and mortality, especially in compensated patients. Increased plasma copeptin is a risk factor for mortality, in particular in decompensated patients. [ABSTRACT FROM AUTHOR]

The prognosis of compensated cirrhosis is good until decompensation. In decompensated cirrhosis, bacterial infections (BIs) are common and increase the risk of death. The incidence and prognostic implications of BIs in compensated cirrhosis are less-well characterized. This study aimed to assess whether BIs influence the risk of decompensation and survival in patients with compensated cirrhosis. This is a cohort study nested to the PREDESCI study, a double-blind, multicenter, randomized controlled trial designed to assess whether β-blockers could prevent decompensation of cirrhosis. Patients with compensated cirrhosis and hepatic venous pressure gradient ≥10 mmHg were included. Development of BIs during follow-up was prospectively registered. Using a competing-risk time-dependent regression analysis, we investigated whether BIs affect the risk of decompensation and survival. Decompensation was defined as development of ascites, bleeding or overt encephalopathy. A total of 201 patients were randomized and followed for a median of 36 months (IQR 24–47 months); 34 patients (17%) developed BIs, which occurred before decompensation in 33 cases, and 29 (14%) developed ascites. Respiratory and urinary tract infections were the most frequent BIs. Decompensation occurred in 26% patients with BIs vs. 16% without BIs. Patients with BIs were at higher risk of decompensation (subdistribution hazard ratio [SHR] 2.93; 95% CI 1.02–8.42; p = 0.047) and of developing ascites (SHR 3.55; 95% CI 1.21–10.47; p = 0.022) than those without BIs. Risk of death was also higher in patients with BIs (subdistribution HR 6.93; 95% CI 2.64–18.18; p <0.001), although decompensation occurred before death in 71% of such cases. BIs have a marked impact on the natural history of compensated cirrhosis, significantly increasing the risk of decompensation, mainly that of ascites, and increasing the risk of death, which usually occurs after decompensation. Our results suggest that BIs may constitute a target to prevent decompensation. It is widely known that bacterial infections are common and increase the mortality risk in patients with decompensated cirrhosis. However, the relevance of bacterial infections in compensated cirrhosis has not been well studied. This study shows that in patients with compensated cirrhosis and clinically significant portal hypertension, bacterial infections occur as frequently as the development of ascites, which is the most frequent decompensating event. Bacterial infections increase the risk of progression to decompensation, mainly by increasing the risk of ascites, and also increase the risk of death, which usually occurs after decompensation. NCT01059396. [Display omitted] • In patients with compensated cirrhosis and CSPH, bacterial infections are as common as ascites. • In compensated patients, bacterial infections increase the risk of decompensation, mainly by increasing the risk of ascites. • Bacterial infections also increase the risk of death in compensated patients, although death usually occurs after decompensation. • Bacterial infections could potentially be targeted to prevent decompensation. [ABSTRACT FROM AUTHOR]

Whether the effect of β-blockers on arterial pressure and/or cardiac function may offset the benefit of reducing portal pressure in advanced cirrhosis is controversial. Herein, we aimed to evaluate the systemic and splanchnic hemodynamic effects of β-blockers in decompensated vs. compensated cirrhosis and to investigate the influence of systemic hemodynamic changes on survival times in decompensated cirrhosis. Patients with cirrhosis and high-risk esophageal varices, without previous bleeding, were consecutively included and grouped according to the presence or absence of decompensation (ascites with or without overt encephalopathy). Systemic and hepatic hemodynamic measurements were performed before starting β-blockers and again after 1 to 3 months of treatment (short-term). Four hundred and three patients were included (190 decompensated and 213 compensated). At baseline, decompensated patients had higher portal pressure than compensated patients and were more hyperdynamic, with higher cardiac output (CO) and lower arterial pressure. Under β-blockers, decompensated patients had lower portal pressure decrease (10 ± 18% vs. 15 ± 12%; p < 0.05) and had greater reductions in heart rate (p < 0.001) and CO (17 ± 15% vs. 10 ± 21%; p < 0.01). Among patients with decompensated cirrhosis, those who died had a greater decrease in CO with β-blockers than survivors (21 ± 14% vs. 15 ± 16%; p < 0.05) and CO under β-blockers independently predicted death by competing-risk regression analysis, with good diagnostic accuracy (C-index 0.74; 95% CI 0.66–0.83). Death risk was higher in decompensated patients with CO <5 L/min vs. CO ≥5 L/min (subdistribution hazard ratio 0.44; 95% CI 0.25–0.77; p = 0.004). In patients with high-risk varices treated to prevent first bleeding, the systemic hemodynamic response to β-blockers is greater and the portal pressure decrease is smaller in those with decompensated cirrhosis. The short-term effect of β-blockers on CO might adversely influence survival in decompensated cirrhosis. β-blockers are often used to reduce the risk of variceal bleeding in patients with cirrhosis. However, it is not known whether the effect of β-blockers on arterial pressure and/or cardiac function may offset the benefit of reducing portal pressure. Herein, we show that in patients with decompensated cirrhosis the potentially detrimental systemic effects of β-blockers are greater than in compensated patients, while the beneficial pressure lowering effects are reduced. The short-term effect of β-blockers on cardiac output may adversely influence survival in patients with decompensated cirrhosis. • Patients with decompensated cirrhosis have different hemodynamic responses to beta blockers than patients with compensated cirrhosis. • Patients with decompensated cirrhosis have greater reductions in CO and smaller reductions in portal pressure. • The effect of beta blockers on CO may reduce survival times of patients with decompensated cirrhosis. • Careful dose titration of beta blockers using non-invasive CO-monitoring may help in patients with decompensated cirrhosis. [ABSTRACT FROM AUTHOR]

Detailed knowledge and understanding of the pathophysiological mechanisms and changes in hepatic and splanchnic function leading to the development of haemodynamic changes and portal hypertension in patients with cirrhosis are essential since it guides the search for targets to ameliorate liver-related abnormalities. Recent research has focused on the gut-liver axis, changes in intestinal permeability, translocation of bacterial products, and inflammation as important drivers of haemodynamic alterations and thereby targets for treatment. Additionally, treatment strategies should focus on microbiotic modulation, antiangiogenics, anti-inflammatory strategies, and modulation of bile acid metabolism. This paper aims to review contemporary pathophysiological-based treatment principles of the major complications of cirrhosis and portal hypertension and future targets for treatment. [ABSTRACT FROM AUTHOR]

Summary: Fluid retention is a common and challenging condition in daily clinical practice. The normal fluid homoeostasis in the human body is based on accurately counter‐balanced physiological mechanisms. When compromised fluid retention occurs and is seen in pathophysiologically different conditions such as liver cirrhosis, heart and kidney failure, and in preeclampsia. These conditions may share pathophysiological mechanisms such as functional arterial underfilling, which seems to be a mutual element in cirrhosis, cardiac failure, cardiorenal and hepatorenal syndromes, and in pregnancy. However, there are also distinct differences and it is still unclear whether kidney dysfunction or arterial underfilling is the initiating factor of fluid retention or if they happen simultaneously. This review focuses on similarities and differences in water retaining conditions and points to areas where important knowledge is still needed. [ABSTRACT FROM AUTHOR]

Cirrhotic cardiomyopathy historically has been confused as alcoholic cardiomyopathy. The key points for diagnosis of cirrhotic cardiomyopathy have been well explained, however this entity was neglected for a long time. Nowadays the diagnosis of this entity has become important because it is a factor that contributes significantly to morbidity-mortality in cirrhotic patients. Characteristics of cirrhotic cardiomyopathy are a hyperdynamic circulatory state, altered diastolic relaxation, impaired contractility, and electrophysiological abnormalities, particularity QT interval prolongation. The pathogenesis includes impaired function of beta-receptors, altered transmembrane currents and overproduction of cardiodepressant factors, such as nitric oxide, cytokines and endogenous cannabinoids. In addition to physical signs of hyperdynamic state and heart failure under stress conditions, the diagnosis can be done with dosage of serum markers, electrocardiography, echocardiography and magnetic resonance. The treatment is mainly supportive, but orthotopic liver transplantation appears to improve this condition although the prognosis of liver transplantation in patients with cirrhotic cardiomyopathy is uncertain.

Nitric oxide synthase is overexpressed in the portal hypertensive (PHT) esophagus, suggesting that expression of other vasoactive mediatora could also be affected. Therefore, in the present study we determined the expression of endothelin-1 (ET-1) and endothelin receptors, which could contribute to the regulation of the vascular tone in PHT esophagus. In esophageal specimens of PHT and sham operated rats, expression of ET-1 and its receptors A and B (ET(A)R and ET(B)R) mRNAs was studied by reverse transcription-polymerase chain reactions. ET-1 protein expression was assessed by immunostaining and enzyme immunoassay. In PHT esophagus, expression of ET-1, ET(A)R and ET(B)R mRNAs was significantly increased by 2.2-, 2.5- and 1.5-fold, respectively, compared with sham operated. The ET-1 protein was significantly increased by 2.2-fold vs. controls as measured by enzyme immunoassay. ET-1 protein was predominantly localized to endothelia of submucosal veins. Thus, portal hypertension induces over-expression of ET-1 in endothelia of esophageal submucosal vessels. Since ET-1 and its receptors could promote vascular proliferation and induce mucosal damage, the overexpressed ET-1 may play an important role in the development and rupture of esophageal varices in portal hypertension.

Abstract We propose that the circulatory impairments produced, in both portal hypertension and liver cirrhosis, to a certain degree resemble those characterizing prenatal life in the fetus. In fact, the left-right circulatory syndrome is common in cirrhotic patients and in the fetus. Thus, in patients with portal hypertension and chronic liver failure, the re-expression of a blood circulation comparable to fetal circulation is associated with the development of similar amniotic functions, i.e., ascites production and placenta functions, and portal vascular enteropathy. Therefore, these re-expressed embryonic functions are extra-embryonic and responsible for prenatal trophism and development. [ABSTRACT FROM AUTHOR]

Introduction: Cirrhosis with portal hypertension and related complications are associated with a high mortality. Excess of circulating vasodilators and cardiodepressive substances lead to a hyperdynamic circulation with changed myocardial structure and function. The entity cirrhotic cardiomyopathy seems to be involved in different aspects of hepatic decompensation, which focuses on new targets of treatment. Areas covered: This review deals with contemporary aspects of cirrhotic cardiomyopathy, and the literature search was undertaken by PubMed with 'cirrhotic' and 'cardiomyopathies' as MeSH Terms. Cirrhotic cardiomyopathy is defined as the presence of systolic and diastolic dysfunction and electrophysiological abnormalities. The diagnosis is based on contemporary Doppler/Echocardiography measurements or quantitative magnetic resonance imaging. Cirrhotic cardiomyopathy is independent of the etiology of the liver disease but related to severity and survival. Expert commentary: The outcome of invasive procedures and liver transplantation is influenced by the presence of cardiac dysfunction. Therefore, a cautious cardiac evaluation should be included in the patient evaluation prior to liver transplantation. Liver transplantation ameliorates most of the abnormalities seen in cirrhotic cardiomyopathy, but no specific treatment can yet be recommended. [ABSTRACT FROM AUTHOR]

Background: Ivabradine is a funny current inhibitor which is administered to patients with congestive heart failure to reduce their heart rate (HR) and attenuate oxidative stress. Chronic liver diseases are characterized by portal hypertension and hyperdynamic circulation with tachycardia. The present study aimed to investigate the effect of ivabradine on portal hypertension. Methods: Male Sprague-Dawley rats received partial portal vein ligation (PVL) to induce portal hypertension. The PVL rats were randomly allocated to receive either vehicle or ivabradine treatment for 10 days. Then the hemodynamic data were collected. The levels of oxidative stress markers and the mRNA expression of nitric oxide synthase (NOS) were measured in the collateral vessel, the superior mesentery artery and the liver. In addition, the collateral vascular responsiveness to arginine vasopressin (AVP) was examined in the ivabradine-treated and vehicle-treated PVL rats. Results: Treatment with ivabradine significantly lowered the HR (174 ± 20 vs. 374 ± 9 beats/min; p < 0.001) and the superior mesentery arterial flow (SMAf) (6.6 ± 0.3 vs. 9.1 ± 0.7 mL/min/100 g BW; p = 0.005) of the PVL rats compared with the control group. The mean arterial pressure, cardiac index, systemic vascular resistance, portal pressure and serum levels of oxidative stress markers were not significantly affected by ivabradine treatment. In addition, the NOS expression and collateral vascular responsiveness to AVP were not significantly influenced by ivabradine treatment, either. Conclusion: Ivabradine reduced the HR and SMAf in PVL rats, which alleviated the hyperdynamic circulatory state and splanchnic hyperemia of portal hypertension. However, whether these effects would help alleviate portal hypertension-related complications requires further clinical investigations. [ABSTRACT FROM AUTHOR]

Portal hypertension develops as a result of increased intrahepatic vascular resistance often caused by chronic liver disease that leads to structural distortion by fibrosis, microvascular thrombosis, dysfunction of liver sinusoidal endothelial cells (LSECs), and hepatic stellate cell (HSC) activation. While the basic mechanisms of LSEC and HSC dysregulation have been extensively studied, the role of microvascular thrombosis and platelet function in the pathogenesis of portal hypertension remains to be clearly characterized. As a secondary event, portal hypertension results in splanchnic and systemic arterial vasodilation, leading to the development of a hyperdynamic circulatory syndrome and subsequently to clinically devastating complications including gastroesophageal varices and variceal hemorrhage, hepatic encephalopathy from the formation of portosystemic shunts, ascites, and renal failure due to the hepatorenal syndrome. This review article discusses: (1) mechanisms of sinusoidal portal hypertension, focusing on HSC and LSEC biology, pathological angiogenesis, and the role of microvascular thrombosis and platelets, (2) the mesenteric vasculature in portal hypertension, and (3) future directions for vascular biology research in portal hypertension. [ABSTRACT FROM AUTHOR]

Liver cirrhosis is associated with a wide range of cardiovascular abnormalities including hyperdynamic circulation, cirrhotic cardiomyopathy, and pulmonary vascular abnormalities. The pathogenic mechanisms of these cardiovascular changes are multifactorial and include neurohumoral and vascular dysregulations. Accumulating evidence suggests that cirrhosis-related cardiovascular abnormalities play a major role in the pathogenesis of multiple life-threatening complications including hepatorenal syndrome, ascites, spontaneous bacterial peritonitis, gastroesophageal varices, and hepatopulmonary syndrome. Treatment targeting the circulatory dysfunction in these patients may improve the short-term prognosis while awaiting liver transplantation. Careful fluid management in the immediate post-transplant period is extremely important to avoid cardiac-related complications. Liver transplantation results in correction of portal hypertension and reversal of all the pathophysiological mechanisms that lead to the cardiovascular abnormalities, resulting in restoration of a normal circulation. The following is a review of the pathogenesis and clinical implications of the cardiovascular changes in cirrhosis.

Cirrhotic cardiomyopathy, a cardiac dysfunction presented in patients with cirrhosis, represents a recently recognized clinical entity. It is characterized by altered diastolic relaxation, impaired contractility, and electrophysiological abnormalities, in particular prolongation of the QT interval. Several mechanisms seem to be involved in the pathogenesis of cirrhotic cardiomyopathy, including impaired function of beta-receptors, altered transmembrane currents, and overproduction of cardiodepressant factors, like nitric oxide, tumor necrosis factor α, and endogenous cannabinoids. Diastolic dysfunction is the first manifestation of cirrhotic cardiomyopathy and reflects the increased stiffness of the cardiac mass, which leads to delayed left ventricular filling. On the other hand, systolic incompetence is presented later, is usually unmasked during pharmacological or physical stress, and predisposes to the development of hepatorenal syndrome. The prolongation of QT is found in about 50 % of cirrhotic patients, but rarely leads to fatal arrhythmias. Cirrhotics with blunted cardiac function seem to have poorer survival rates compared to those without, and the risk is particularly increased during the insertion of transjugular intrahepatic portosystemic shunt or liver transplantation. Till now, there is no specific treatment for the management of cirrhotic cardiomyopathy. New agents, targeting to its pathogenetical mechanisms, may play some role as future therapeutic options. [ABSTRACT FROM AUTHOR]

Acute or chronic insults to the liver are usually followed by a tissue repairing process. Unfortunately, this action, in most cases, is not effective enough to restore the normal hepatic structure and function. Instead, fibrogenesis and regenerative nodules formation ensue, which are relatively nonfunctioning. The common final stage of the process is liver cirrhosis with increased intrahepatic resistance to portal venous blood flow. Throughout the entire course, the extrahepatic circulatory dysfunction, including increased splanchnic blood flow, elevated portal venous blood flow and pressure, decreased splanchnic and peripheral vascular resistance, tachycardia, and increased cardiac output, are noted and denoted as portal hypertension with hyperdynamic circulatory dysfunction. When such a condition is established, patients may suffer from fatal complications such as gastroesophageal variceal hemorrhage, hepatic encephalopathy, or hepatorenal syndrome. The cause of such a circulatory dysfunction is not fully elucidated. Nevertheless, clarification of the pathophysiology definitely contributes to the control of portal hypertension-related complications. Herein, the molecular mechanism of this intriguing disaster is reviewed and discussed. [ABSTRACT FROM AUTHOR]