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Hepatitis B virus (HBV) infection causes oxidative stress (OS) and alters mitochondria in experimental models. Our goal was to investigate whether HBV might alter liver mitochondria also in humans, and the resulting mitochondrial stress might account for the progression of fibrosis in chronic hepatitis B (CHB).The study included 146 treatment-naïve CHB mono-infected patients. Patients with CHB and advanced fibrosis (AF) or cirrhosis (F3-F4) were compared to patients with no/mild-moderate fibrosis (F0-F2). Patients with CHB were further compared to patients with chronic hepatitis C (CHC; n = 33), nonalcoholic steatohepatatis (NASH; n = 12), and healthy controls (n = 24). We detected oxidative damage to mitochondrial DNA (mtDNA), including mtDNA strand beaks, and identified multiple mtDNA deletions in patients with F3-F4 as compared to patients with F0-F2. Alterations in mitochondrial function, mitochondrial unfolded protein response, biogenesis, mitophagy, and liver inflammation were observed in patients with AF or cirrhosis associated with CHB, CHC, and NASH. In vitro, significant increases of the mitochondrial formation of superoxide and peroxynitrite as well as mtDNA damage, nitration of the mitochondrial respiratory chain complexes, and impairment of complex I occurred in HepG2 cells replicating HBV or transiently expressing hepatitits B virus X protein. mtDNA damage and complex I impairment were prevented with the superoxide-scavenging Mito-Tempo or with inducible nitric oxide synthase (iNOS)-specific inhibitor 1400 W.Our results emphasized the importance of mitochondrial OS, mtDNA damage, and associated alterations in mitochondrial function and dynamics in AF or cirrhosis in CHB and NASH. Mitochondria might be a target in drug development to stop fibrosis progression.

Microvesicles (MVs) are extracellular vesicles released by cells following activation or apoptosis. Some MV subpopulations augment with cirrhosis severity and contribute to portal hypertension. This study aimed at determining if plasma MV levels can estimate the presence of hepatic venous pressure gradient (HVPG) ≥10 mm Hg and predict mortality in patients with advanced chronic liver disease. All patients with severe fibrosis or cirrhosis undergoing liver catheterization between 2013 and 2015 at two centers were prospectively included. We measured circulating levels of annexin V+ , platelet, leukocyte, endothelial, and hepatocyte MVs. The test cohort included 139 patients. Hepatocyte MV levels were 4.0-fold and 2.2-fold higher in patients with Child-Pugh C than in those with Child-Pugh A or B liver disease, respectively. Levels of other MV subpopulations were not influenced by liver disease severity. Hepatocyte MV levels correlated with HVPG but could not identify patients with HVPG ≥10 mm Hg. Hepatocyte MV level >65 U/L predicted 6-month mortality independently of Child-Pugh score and of Model for End-Stage Liver Disease (MELD). Patients with hepatocyte MV levels >65 U/L and MELD >15 had a higher 6-month mortality than other patients (23% versus 3%; P = 0.001). These findings were confirmed in a validation cohort including 103 patients. Conclusion Circulating MV levels cannot identify patients with HVPG ≥10 mm Hg; by contrast, hepatocyte MV levels strongly improve prediction of 6-month mortality in patients with advanced chronic liver disease; therapies associated with decreased levels of circulating hepatocyte MV might be attractive strategies in patients with severe cirrhosis. (Hepatology 2018).

In patients with chronic hepatitis C (CHC), cirrhosis is associated with age, gender, diabetes, alcohol abuse, and coinfection with human immunodeficiency virus (HIV) or hepatitis B virus (HBV). The effect of these factors on the outcome of cirrhosis is unknown. This study in CHC patients with cirrhosis aimed to assess the influence of these factors on decompensation, liver transplantation, and death. Consecutive patients with CHC and cirrhosis hospitalized between January 1, 2006 and December 31, 2008 were followed up until death, transplantation, or study closure in March 2013. Gender, age, Model for End-Stage Liver Disease (MELD) score, diabetes, alcohol abuse, HIV, or HBV coinfection were collected at inclusion. The complications of cirrhosis, death, and liver transplantation were recorded at inclusion and during follow-up. The association between baseline factors and liver-related outcomes at inclusion and during follow-up were tested using logistic regression and Cox's model, respectively. A total of 348 patients with CHC and cirrhosis (68% men; median age: 59 years; median MELD: 10) were included. At baseline, 40% of the patients had diabetes, 29% alcohol abuse, and 6% HIV or HBV coinfection. Baseline MELD ≥10 (P

Simultaneous liver and kidney transplantation (SLKT) remains the procedure of choice for patients with both endstage liver disease and kidney failure. Stringent guidelines are needed to avoid unnecessary kidney transplantation. A recent consensus meeting proposed criteria based on the Modified Diet in Renal Disease (MDRD)-6 equation to estimate glomerular filtration rate (GFR). The aims of this study were to compare GFR equations to true GFR in candidates for liver transplantation (LT) and to determine the impact of inaccuracies on the current guidelines for SLKT. Three hundred stable cirrhosis patients evaluated for LT were studied. All patients had iohexol clearance to measure GFR at evaluation under stable conditions. Measured GFR (mGFR) was compared to MDRD-4, MDRD-6, and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. MDRD-6 was the most accurate equation to predict GFR. In the 290 patients with mGFR >30 mL/min/1.73 m2, 15 patients (7%) had estimated GFR (eGFR) ≤40 mL/min/1.73 m2 based on the MDRD-6 equation, defining “discordant” patients. Among them, two underwent SLKT and 13 underwent LT alone. None of those who survived more than 1 year after LT alone (n = 8) developed renal dysfunction thereafter. In multivariate analysis, discordant patients were older (P = 0.03) and had lower sodium level (P = 0.02). Conclusion: The MDRD-6 equation was superior to other equations at identifying cirrhosis patients with true GFR 30 mL/min/1.73 m2, with a potential risk of unnecessary kidney transplantation if applying current U.S. recommendations for SLKT. (Hepatology 2014;59:1514-1521)

Beta-blockers may have a negative impact on survival in patients with cirrhosis and refractory ascites. The aim of this study was to evaluate the effect of the administration of betablockers on long-term survival in patients with cirrhosis and refractory ascites. We performed a single-center, observational, case-only, prospective study of patients with cirrhosis and refractory ascites who did or did not receive beta-blockers for the prevention of gastrointestinal bleeding; 151 patients were included. The mean Model for End-Stage Liver Disease score was 18.8 6 4.1. All patients regularly underwent large-volume paracentesis and intravenous albumin administration. Seventy-seven patients (51%) were treated with propranolol (113 6 46 mg/day). The median follow-up for the whole group was 8 months. The median survival time was 10 months [95% confidence interval (CI) 5 8-12 months]. The probability of survival at 1 year was 41% (95% CI 5 33%-49%). The clinical characteristics and laboratory values at enrolment were not significantly different between patients who were receiving propranolol and those who were not. The median survival time was 20.0 months (95% CI 5 4.8-35.2 months) in patients not treated with propranolol and 5.0 months (95% CI 5 3.56.5 months) in those treated with propranolol (P 5 0.0001). The 1-year probability of survival was significantly lower in patients who received propranolol [19% (95% CI 5 9%29%)] versus those who did not [64% (95% CI 5 52%-76%), P < 0.0001]. The independent variables of mortality were Child-Pugh class C, hyponatremia and renal failure as causes of refractory ascites, and beta-blocker therapy. Conclusion: The use of beta-blockers is associated with poor survival in patients with refractory ascites. These results suggest that betablockers should be contraindicated in these patients. (HEPATOLOGY 2010;52:1017-1022)

Sepsis is physiologically viewed as a proinflammatory and procoagulant response to invading pathogens. There are three recognized stages in the inflammatory response with progressively increased risk of end-organ failure and death: sepsis, severe sepsis, and septic shock. Patients with cirrhosis are prone to develop sepsis, sepsis-induced organ failure, and death. There is evidence that in cirrhosis, sepsis is accompanied by a markedly imbalanced cytokine response ("cytokine storm"), which converts responses that are normally beneficial for fighting infections into excessive, damaging inflammation. Molecular mechanisms for this excessive proinflammatory response are poorly understood. In patients with cirrhosis and severe sepsis, high production of proinflammatory cytokines seems to play a role in the worsening of liver function and the development of organ/system failures such as shock, renal failure, acute lung injury or acute respiratory distress syndrome, coagulopathy, or hepatic encephalopathy. In addition, these patients may have sepsis-induced hyperglycemia, defective arginine-vasopressin secretion, adrenal insufficiency, or compartmental syndrome. In patients with cirrhosis and spontaneous bacterial peritonitis (SBP), early use of antibiotics and intravenous albumin administration decreases the risk for developing renal failure and improves survival. There are no randomized studies that have been specifically performed in patients with cirrhosis and severe sepsis to evaluate treatments that have been shown to improve outcome in patients without cirrhosis who have severe sepsis or septic shock. These treatments include recombinant human activated C protein and protective-ventilation strategy for respiratory failure. Other treatments should be evaluated in the cirrhotic population with severe sepsis including the early use of antibiotics in "non-SBP" infections, vasopressor therapy, hydrocortisone, renal-replacement therapy and liver support systems, and selective decontamination of the digestive tract or oropharynx.

High-density lipoproteins (HDL) are known to neutralize lipopolysaccharide (LPS). Because patients with cirrhosis have lower HDL levels, this may contribute to LPS-induced ex vivo monocyte overproduction of proinflammatory cytokines. However, the effects of HDL on cytokine production by monocytes from patients with cirrhosis have never been studied. The aim of this study was to determine the effects of HDL on LPS-induced proinflammatory cytokine production in whole blood and isolated monocytes from patients with severe cirrhosis and controls. Plasma levels of HDL and cytokines were determined. The effects of reconstituted HDL (rHDL) on LPS-induced cytokine production in whole blood were assessed by cytokine array and on tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) production in isolated monocytes. Plasma HDL levels were significantly lower in patients with cirrhosis than in controls. Plasma levels of TNF-α and IL-6 were significantly higher in patients with cirrhosis than in controls. Incubation of rHDL with whole blood prevented LPS-induced TNF-α and IL-6 overproduction in patients with cirrhosis. LPS-induced TNF-α production and CD14 expression were significantly more marked in cirrhotic monocytes than in control monocytes, and both decreased significantly after rHDL incubation. LPS-induced down-regulation of scavenger receptor, class B, type I (SR-BI) expression was abolished in cirrhotic monocytes. Conclusions: This study shows that rHDL abolishes the LPS-induced overproduction of proinflammatory cytokines in whole blood from patients with severe cirrhosis. These results were confirmed in isolated monocytes from these patients. This suggests that administration of rHDL might be a useful strategy for the treatment of cirrhosis to limit LPS-induced cytokine overproduction. (HEPATOLOGY 2009;49:175-184.)

In patients with cirrhosis and type 1 hepatorenal syndrome (HRS), systemic vasodilation, which is mainly attributable to splanchnic vasodilation, plays a critical role in the activation of endogenous vasoconstrictor systems, resulting in renal vasoconstriction and functional renal failure. It has been suggested that the use of splanchnic (and systemic) vasoconstrictors such as terlipressin (a vasopressin analog) or alpha-1-adrenoceptor agonists (midodrine or noradrenaline) may improve renal function in patients with type 1 HRS. Six studies (with only one randomized study in a small series of patients) have shown that terlipressin improves renal function in these patients. However, there is evidence that terlipressin alone may be less effective than terlipressin combined with intravenous albumin in improving renal function. Future randomized studies should confirm this difference and evaluate the impact of terlipressin therapy (with or without intravenous albumin) on survival. Interestingly, in nonrandomized studies, the use of alpha-1 agonists combined with other therapies (octreotide and albumin for midodrine; furosemide and albumin for noradrenaline) has been shown to improve renal function in patients with type 1 HRS. The efficacy and safety of combined therapies including alpha-1 agonists should be confirmed in randomized studies. Finally, preliminary evidence suggests that vasoconstrictor administration may be a novel therapeutic approach targeting vasodilation involved in the mechanism of: (1) renal failure in type 2 HRS; (2) paracentesis-induced circulatory dysfunction; and (3) arterial hypotension induced by byproducts of gram-negative bacteria. Further studies are needed in all these fields.

In patients with cirrhosis, acute renal failure is mainly due to prerenal failure (caused by renal hypoperfusion) and tubular necrosis. The main causes of prerenal failure are "true hypovolemia" (induced by hemorrhage or gastrointestinal or renal fluid losses), sepsis, or type 1 hepatorenal syndrome (HRS). The frequency of prerenal failure due to the administration of nonsteroidal anti-inflammatory drugs or intravascular radiocontrast agents is unknown. Prerenal failure is rapidly reversible after restoration of renal blood flow. Treatment is directed to the cause of hypoperfusion, and fluid replacement is used to treat most cases of "non-HRS" prerenal failure. In patients with type 1 HRS with very low short-term survival rate, liver transplantation is the ideal treatment. Systemic vasoconstrictor therapy (with terlipressin, noradrenaline, or midodrine [combined with octreotide]) may improve renal function in patients with type 1 HRS waiting for liver transplantation. MARS (for molecular adsorbent recirculating system) and the transjugular intrahepatic portosystemic shunt may also improve renal function in these patients. In patients with cirrhosis, acute tubular necrosis is mainly due to an ischemic insult to the renal tubules. The most common condition leading to ischemic acute tubular necrosis is severe and sustained prerenal failure. Little is known about the natural course and treatment (i.e., renal replacement therapy) of cirrhosis-associated acute tubular necrosis.

Portopulmonary hypertension represents a major risk factor for transplantation; therefore, preoperative detection is crucial. The aims of this study were to determine (1) whether Doppler echocardiography performed at evaluation is a reliable tool for detecting portopulmonary hypertension and (2) the incidence of acquired portopulmonary hypertension profile after evaluation. One hundred sixty-five patients had Doppler echocardiography and right heart catheterization at evaluation over a 9-year period. All patients had a prospective follow-up, and the results of catheterization at evaluation were compared with those obtained at the time of transplantation. Seventeen of 165 patients met the criteria for portopulmonary hypertension on Doppler echocardiography. Portopulmonary hypertension was confirmed by catheterization in 10 patients and ruled out in 7. There were no false negatives for echocardiography. Mean pulmonary artery pressure was significantly higher during the initial phase of transplantation than at evaluation (17.8 +/- 4.3 vs. 20.3 +/- 5.5 mm Hg, respectively, P

Cardiac hepatopathy, hepatic injury caused by cardiac dysfunction, is a common entity but has been characterized incompletely, particularly the relationship between hemodynamics and histology. We aimed to describe the clinical, biochemical, hemodynamic, and histologic characteristics of this disorder. Eighty-three patients from 2 tertiary referral centers were studied. Patients were divided into 3 groups based on the duration of cardiac dysfunction: (1) acute (n = 12); (2) chronic (n = 53); and (3) acute on chronic (n = 18). Results showed that serum aminotransferase levels were increased typically, particularly in the acute group (median aspartate aminotransferase level was 30.2 times the upper limit of normal [range, 1-100]; P

In cirrhosis, lipopolysaccharide (LPS, a product of Gram-negative bacteria) in the blood may cause septic shock. LPS-elicited induction of arterial inducible nitric oxide synthase (iNOS) results in nitric oxide (NO)-induced vasodilation, which causes arterial hypotension and hyporeactivity to alpha(1)-adrenergic constrictors. In vitro studies have suggested that vasopressin inhibits iNOS expression in cultured vascular smooth muscle cells exposed to LPS. Thus, the aim of this study was to investigate the effects of terlipressin administration (a vasopressin analog) on in vivo LPS-induced aortic iNOS in rats with cirrhosis. LPS (1 mg/kg, intravenously) was administered followed by the intravenous administration of terlipressin (0.05 mg/kg, intravenously) or placebo 1 hour later. Arterial pressure was measured, and contractions to phenylephrine (an alpha(1)-adrenoceptor agonist), iNOS activity, and iNOS expressions (mRNA and protein) were investigated in isolated aortas. LPS-induced arterial hypotension and aortic hyporeactivity to phenylephrine were abolished in rats that received terlipressin. LPS-induced aortic iNOS activity and expression were suppressed in terlipressin-treated rats. In conclusion, in LPS-challenged rats with cirrhosis, terlipressin administration inhibits in vivo LPS-induced aortic iNOS expression. Terlipressin administration may be a novel approach for the treatment of arterial hypotension and hyporeactivity to alpha(1)-adrenergic constrictors in patients with cirrhosis and septic shock.

Hyporeactivity to vasoconstrictors in aortae from portal vein-stenosed rats is associated with an increased activity of endothelial NO synthase (NOS3). In contrast, during sepsis, which is common in cirrhosis, vascular hyporeactivity is associated with an induction of inducible NOS2. The aim of this study was to investigate the in vitro reactivity to phenylephrine and the regulation of NOS2 and NOS3 in aortae from portal vein-stenosed rats after lipopolysaccharide (LPS) administration. Aortic vascular reactivity for phenylephrine, aortic NOS activity, and NOS2 and NOS3 protein expression were determined 5 hours after intravenous LPS or saline administration. Moreover, aortic NOS activity was measured after 5-hour in vitro incubation in LPS. LPS induced a significantly smaller decrease in aortic tension in portal vein-stenosed than in sham-operated rats. Under baseline conditions, aortic NOS activity and NOS3 protein expression were higher in portal vein-stenosed than in sham-operated rats, and NOS2 protein expression was not detected in aortae from either group. After LPS administration, NOS activity and NOS2 protein expression increased significantly less in portal vein-stenosed than in sham-operated rat aortae. Similar results were obtained after in vitro incubation with LPS. Endothelium removal or NOS3 inhibition with the calmodulin inhibitor, W7, increased NOS activity in the aortae of portal vein-stenosed rats after LPS incubation. In conclusion, in aortae of portal vein-stenosed rats exposed to LPS, no further decrease in aortic reactivity to phenylephrine was observed, and the induction of NOS2 was down-regulated. Endothelium removal or calmodulin inhibition inhibits NOS3 overactivity and leads to normalized NOS2 activation after LPS in aortae from portal vein-stenosed rats.

Protein kinase C (PKC) modulates the activity and phosphorylation of the catalytic alpha-subunit of sodium-potassium-adenosine triphosphatase (Na+/K+ ATPase) in normal arteries. Because PKC is altered in cirrhotic aortae, Na+/K+ ATPase may also be altered in these arteries. The aim of the present study was to investigate alpha-subunit activity and phosphorylation in aortae from normal and cirrhotic rats, under baseline conditions and during exposure to PKC modulators. Alpha-subunit activity was assessed by measuring the amount of 32P released by hydrolysis of [gamma-32P]ATP in freshly isolated cell membranes (in the absence of PKC modulators only) and membrane depolarization caused by ouabain-induced alpha-subunit inhibition in isolated aortae (in the absence and presence of PKC modulators). Alpha-subunit phosphorylation was assessed by incorporation of 32P into alpha-subunits. Staurosporine, a PKC inhibitor, and phorbol 12,13-dibutyrate (PDBU), a PKC activator, were used. In addition, alpha-subunit expression was studied by Western blot analysis. In the absence of PKC modulators, the amount of 32P released by hydrolysis of [gamma-32P]ATP and ouabain-induced membrane depolarization were significantly lower in cirrhotic than in normal aortae. Staurosporine suppressed ouabain-induced membrane depolarization in cirrhotic and normal arteries. Ouabain-induced membrane depolarization was similar in cirrhotic aortae exposed to PDBU and in normal arteries studied under baseline conditions. Alpha-subunit phosphorylation was significantly lower in cirrhotic than in normal aortae, in aortae under baseline conditions, and in arteries exposed to staurosporine. Phosphorylation of the alpha-subunit was similar in cirrhotic aortae exposed to PDBU and in normal arteries under baseline conditions. Western blot analysis showed that the amount of alpha-subunit did not significantly differ between cirrhotic and normal aortae. In conclusion, a decrease in baseline Na+/K+ ATPase alpha-subunit activity occurs in aortae from cirrhotic rats as a result of reduced basal PKC activity. This PKC-dependent decreased alpha-subunit activity may be caused by a reduction in PKC-induced alpha-subunit phosphorylation.

In patients with cirrhosis, the plasma level of endothelin, a potent vasoconstrictor peptide, is elevated, and endothelin plays a role in increased intrahepatic vascular resistance. Thus, the aim of this study was to evaluate the hemodynamic effects of bosentan, a mixed ET(A) and ET(B) endothelin receptor antagonist in three models of portal hypertension. In all groups of rats, endothelin (2 microg/kg intravenously) administration significantly increased intrahepatic vascular resistance. In rats with secondary biliary cirrhosis, bosentan (30 mg/kg) significantly reduced portal pressure from 14.6 +/- 1.2 to 12.1 +/- 0.6 mm Hg, while portal blood flow and cardiac output increased by 45% and 57%, respectively. Thus, hepatocollateral vascular resistance decreased significantly from 177 +/- 19 to 101 +/- 9 dyn x s x cm(-5) x 10(-3). Similar results were observed in rats with CCl4-induced cirrhosis. In isolated perfused cirrhotic rat livers, bosentan (1 to 100 micromol/L) had no significant effect on hepatic vascular resistance. In portal vein-stenosed rats, bosentan administration significantly decreased portal pressure from 13.1 +/- 0.6 to 11.4 +/- 0.5 mm Hg by reducing portosystemic vascular resistance, because bosentan had no effect on vascular resistance of normal rat liver. In conclusion, bosentan administration decreased portal pressure in vivo by reducing hepatocollateral vascular resistance in rats with cirrhosis. Thus, mixed endothelin receptor antagonists might be a new approach in the pharmacological treatment of portal hypertension.

Among 68 liver transplant recipients, 190 hemodynamic studies were performed to evaluate the role of sepsis, anemia, acute graft rejection, and persistent portosystemic shunts. The hemodynamic outcome after orthotopic liver transplantation (OLT) in stable patients was also determined. Patients with sepsis showed a significant increase in cardiac index (5.1 +/- 0.9 vs. 3.4 +/- 0.7 L/min m2) and hepatic venous pressure gradient (6.3 +/- 2.9 vs. 3.3 +/- 2.1 mm Hg), compared with patients without sepsis. Cardiac index was higher in patients with, than in patients without, anemia (4.1 +/- 0.6 vs. 3.0 +/- 0.6 L/min m2). The hepatic venous pressure gradient was higher in patients with than in patients without acute graft rejection (5.1 +/- 2.9 vs. 2.6 +/- 1.2 mm Hg). Among patients with acute rejection, the hepatic venous pressure gradient was higher in patients with severe rejection than in those with moderate or mild rejection (7.2 +/- 3.3 vs. 4.6 +/- 2.4 and 2.8 +/- 0.9 mm Hg). In the postoperative period, in patients undergoing transplantation for acute liver failure, the hepatic blood flow was normal and significantly lower than in patients receiving transplant for cirrhosis (1.15 +/- 0.37 vs. 1.96 +/- 0.71 L/min). In patients undergoing transplantation for cirrhosis, cardiac index, azygos, and hepatic blood flows significantly decreased after 1 year compared with the first 6 postoperative months. Multivariate analysis showed that sepsis, anemia, and time after OLT were independent variables influencing cardiac index. Sepsis, time after OLT, and the existence of portosystemic shunts were independent variables influencing hepatic blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Although prostaglandins are thought to be involved in the hyperdynamic circulation of portal hypertension, the role of this substance has not been elucidated. Dose-response curves, the hemodynamic effects of prostacyclin (20 micrograms/kg) and its inhibitor indomethacin and measurements of plasma and urinary levels of 6-keto-prostaglandin F1 alpha were compared in three groups of six rats each: normal, with portal vein stenosis and with secondary biliary cirrhosis. Plasma and urinary levels of 6-keto-prostaglandin F1 alpha were higher in rats with portal vein stenosis and cirrhotic rats than in normal rats. Dose-response curves showed similar maximal decreases in arterial pressure in the three groups, whereas the maximal increase in portal pressure was less marked in cirrhotic rats than in normal rats and rats with portal vein stenosis. In normal rats, prostacyclin increased cardiac output by 21% and portal pressure by 41%. Similar increases were observed in rats with portal vein stenosis. In contrast, prostacyclin did not affect cardiac output and portal pressure in cirrhotic rats. Indomethacin induced a more marked vasoconstrictive effect in normal rats than in cirrhotic rats. This study shows that prostacyclin plays a role in the hemodynamic alterations in portal hypertension. Moreover, the hyporeactivity observed in cirrhotic rats suggests that prostacyclin plays a major role in the circulatory changes of portal hypertension due to chronic liver disease.

Because it has been hypothesized that the hyperkinetic circulation in portal hypertension is the result of increased synthesis of nitric oxide, we compared the hemodynamic effects of nitric oxide synthesis—specific agonist (L-arginine) and antagonist between normal and cirrhotic conscious rats. The dose-response curves showed that L-arginine significantly decreased arterial pressure and increased heart rate. These changes started at the 200 mg/kg dose and were similar in both groups of rats. In both groups of rats NG-monomethyl—L-arginine (25 mg/kg) significantly decreased cardiac output by 35%. In cirrhotic rats, NG-monomethyl—Larginine decreased portal pressure from 15.3 ± 0.9 mm Hg to 13.6 ± 0.7 mm Hg and portal tributary blood flow from 7.8 ± 0.7 ml · min−1 · 100 gm−1 to 5.9 ± 0.7 ml · min−1 · 100 gm−; it significantly increased portal territory vascular resistance from 950 ± 108 dyn · sec · cm−5 · 100 gm−1 × 103 to 1,579 ± 258 dyn · sec · cm−5 · 100 gm−1 × 103. In normal rats, portal tributary blood flow decreased similarly, by 27%, and portal territory vascular resistance increased by 55%. In neither group was hepatic arterial blood flow altered. Before and after NG-monomethyl-L-arginine administration, arterial cyclic GMP concentrations were not significantly different between normal and cirrhotic rats. In conclusion, this study shows evidence of a normal role for nitric oxide—mediated vasodilatation in rats with cirrhosis and that inhibition of nitric oxide synthesis reduces portal hypertension. These results did not support the hypothesis that nitric oxide synthesis is increased in cirrhosis. (HEPATOLOGY 1992;16:980–983.)

Although arterial vasodilation is a well-known feature in patients with cirrhosis, the venous system remains unexplored. To measure total effective vascular compliance, a reflection of the properties of the venous system, rapid volume expansion (300 ml of a gelatin solution in 3 min) was performed in 23 patients. Eleven patients had compensated cirrhosis (Child-Pugh grade A or B), and eight had decompensated cirrhosis (Child-Pugh grade C). Four control patients had mild chronic hepatitis, normal hepatic venous pressure and normal liver architecture. Cardiac index, hepatic venous pressures, hepatic and azygos blood flow and renal plasma flow were measured before and immediately after volume expansion. Right atrial pressure was recorded during volume expansion. This allowed the calculation of total effective vascular compliance, which was higher in patients with decompensated cirrhosis than in those with compensated cirrhosis (4.65 +/- 4.21 vs. 1.34 +/- 0.63 ml.mm Hg-1.kg-1; p less than 0.05). In response to volume expansion, renal vascular resistance decreased significantly in patients with compensated cirrhosis, but not in those with decompensated cirrhosis (-30% +/- 33% vs. +2% +/- 23%; p less than 0.05). No change was seen in glomerular filtration rate. Systemic oxygen consumption increased in patients with compensated cirrhosis, but not in those patients with decompensated cirrhosis (25% +/- 33% vs. -4% +/- 9%; p less than 0.05). Although in all patients with cirrhosis volume expansion increased central venous pressures, azygos blood flow and the hepatic venous pressure gradient did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

In patients with cirrhosis, the significance of elevated plasma catecholamine concentrations is unclear. Thus we investigated the relationship between plasma catecholamine concentrations and the hemodynamic effect of pindolol (an index of sympathetic vascular tone) in 10 patients with cirrhosis. Systemic and splanchnic hemodynamics and plasma catecholamine concentrations in the pulmonary artery and the splanchnic veins (hepatic and azygos veins) were studied before and after the oral administration of pindolol (20 mg). In basal conditions patients exhibited a hyperkinetic circulatory syndrome and elevated plasma catecholamine concentrations. Alterations in basal hemodynamics were correlated with plasma epinephrine concentrations but not with norepinephrine. Pindolol administration significantly decreased heart rate and increased right atrial pressure. After pindolol administration, individual hemodynamic changes (cardiac index, systemic vascular resistance, wedged hepatic venous pressure) were significantly correlated with plasma catecholamine concentrations. In conclusion, this study shows that in cirrhotic patients epinephrine may play a role in hemodynamic alterations, and plasma catecholamine concentrations are an index of sympathetic vascular tone. (HEPATOLOGY 1992;15:58-62).

In patients with cirrhosis, vasopressin infusion induces sustained vasoconstriction and elevation of arterial pressure. The vasopressor effect could be caused by impairment of mechanisms normally aimed at buffering increases in arterial pressure (reflex bradycardia and decreases in arteriolar resistance). We studied the acute effects of continuous vasopressin infusion (0.4 IU/min) on systemic hemodynamics in seven patients with cirrhosis and in six patients without cirrhosis (controls). Vasopressin effects on systemic O2 consumption were also studied. In both groups, vasopressin infusion induced similar peak increases in arterial pressure, followed by similar decreases in heart rate and cardiac output. However, cirrhotic patients and controls differed 30 min after the start of vasopressin infusion. At 30 min, mean arterial pressure, diastolic arterial pressure and systemic vascular resistance remained significantly higher than preinfusion values in patients with cirrhosis. No decrease in systemic O2 consumption occurred in cirrhotic patients. In controls, at 30 min, mean arterial pressure and diastolic arterial pressure had returned to baseline. Systemic vascular resistance was not significantly higher than the preinfusion value and systemic O2 consumption had significantly decreased to below preinfusion values. We conclude that the vasopressor effect of vasopressin is abnormally sustained in patients with cirrhosis. This might be caused by insufficient buffering of vasopressin-induced arteriolar constriction rather than by abnormal vagal control of heart rate. In turn, as suggested by the lack of a decrease in systemic O2 consumption, persistent arteriolar constriction might be related to abnormally sustained sympathetic vascular tone in patients with cirrhosis.

To elucidate the relationship between oxygen transport and uptake in cirrhosis, we studied the effects of three vasoactive drugs that change O2 transport. Systemic hemodynamics, blood gases and lactate concentration were measured in patients with alcoholic cirrhosis before and after intravenous dobutamine, propranolol and nitroglycerin. Nine patients received successively dobutamine and then propranolol. Ten patients received nitroglycerin. Three other patients without cirrhosis (controls) received dobutamine. In patients with cirrhosis, dobutamine infusion was accompanied by a significant increase in cardiac output (+21%), systemic O2 transport (+21%) and O2 uptake (+12%), whereas O2 extraction ratio and arterial lactate concentration did not change significantly. Propranolol administration was followed by a significant decrease in cardiac output (-24%) and systemic O2 transport (-25%) and a significant increase in O2 extraction ratio (+19%), whereas O2 uptake and arterial lactate concentration did not change. Nitroglycerin infusion was accompanied by a significant decrease in cardiac output (-21%), systemic O2 transport (-26%) and O2 uptake (-10%), whereas O2 extraction ratio (+18%) and arterial lactate concentration (+31%) significantly increased. In control patients, dobutamine infusion was accompanied by an increase in cardiac output and in systemic O2 transport and by a decrease in O2 extraction ratio, whereas O2 uptake was not modified. These results suggest that O2 uptake may be abnormally dependent on O2 transport in patients with cirrhosis.