ACG Clinical Guideline: disorders of the hepatic and mesenteric circulation

Disorders of the mesenteric, portal, and hepatic veins and mesenteric and hepatic arteries have important clinical consequences and may lead to acute liver failure, chronic liver disease, noncirrhotic portal hypertension, cirrhosis, and hepatocellular carcinoma. Although literature in the field of vascular liver disorders is scant, these disorders are common in clinical practice, and general practitioners, gastroenterologists, and hepatologists may benefit from expert guidance and recommendations for management of these conditions. These guidelines represent the official practice recommendations of the American College of Gastroenterology. Key concept statements based on author expert opinion and review of literature and specific recommendations based on PICO/GRADE analysis have been developed to aid in the management of vascular liver disorders. These recommendations and guidelines should be tailored to individual patients and circumstances in routine clinical practice.

Repeatability of the "flash-replenishment" method in contrast-enhanced ultrasound for the quantitative assessment of hepatic microvascular perfusion

This study aimed to evaluate the feasibility and repeatability of the flash-replenishment method in contrast-enhanced ultrasound (CEUS) perfusion imaging and assess quantitatively microvascular perfusion in the liver. Twenty healthy New Zealand rabbits were submitted to CEUS perfusion imaging with continuous intravenous infusion. Using flash-replenishment kinetics, the dynamic process of depletion and refilling of microbubble contrast agent was recorded. The hepatic microvascular perfusion parameters were calculated, including region of interest, peak intensity (PI), area under the curve (AUC), and hepatic artery to vein transit time (HA-HVTT). A consistency test was performed for multiple measurements by the same operator and blind measurements by two different operators. The hepatic perfusion imaging of 3×108 bubbles/min had minimal error and the best imaging effect and repeatability. The variability of the perfusion parameter measured at 3 cm depth under the liver capsule was at a minimum with coefficient of variation of 3.9%. The interclass correlation coefficient (ICC) of measurements taken by the same operator was 0.985, (95% confidence interval, CI=0.927-0.998). Measurements taken by two operators had good consistency and reliability, with the ICC of 0.948 (95%CI=0.853-0.982). The PI and AUC of liver parenchyma after reperfusion were lower than before blocking; and HA-HVTT was significantly longer than before blocking (P<0.05). The flash-replenishment method in CEUS perfusion imaging showed good stability and repeatability, which provide a valuable experimental basis for the quantitative assessment of hepatic microvascular perfusion in clinical practice.

Portal Vein Dopplerflowmetry in healthy sheep according to age / Dopplerfluxometria da veia portal em ovinos hígidos de acordo com a idade

Pulsed Doppler ultrasound was used to evaluate portal blood flow, portal velocity and portal congestion index in 24 healthy sheep divided into groups (lambs, yearlings and ewes), according to age. Measurements were performed at the 11th right intercostal space using ideal insonation angle and uniform insonation method. Mean values obtained in each group were compared with one-way ANOVA, followed by Tukey post-hoc test. Portal velocity and portal blood flow were statistically similar between the groups (P>0.05). Mean portal velocity were 17.75; 17.13 and 16.75; while mean portal blood flow were 26.65; 31.04 and 24.32 for lambs, yearlings and ewes, respectively. Portal congestion index was statistically distinct between the groups and values for lambs, yearlings and ewes were 0.009; 0.058 and 0.09, respectively (P<0.01). Statistical differences were observed in portal vein diameter, portal vein area and portal congestion index between the groups, presumably due to influence of weight and not to age.(AU)

A ultrassonografia com Doppler pulsado foi utilizado para avaliar o fluxo sanguíneo portal, velocidade portal e índice de congestão portal em 24 ovinos saudáveis divididos em grupos (cordeiros, borregos e ovelhas), de acordo com a idade. As medições foram realizadas no 11o espaço intercostal direito utilizando ângulo de insonação ideal e método de inclusão uniforme. Os valores médios obtidos em cada grupo foram comparados com ANOVA, seguido pelo teste post-hoc de Tukey. A velocidade portal e o fluxo de sangue portal foram estatisticamente semelhantes entre os grupos (P>0,05). A velocidade portal média foram 17,75; 17,13 e 16,75; enquanto o fluxo de sangue portal médios foram 26,65; 31,04 e 24,32 para cordeiros, borregos e ovelhas, respectivamente. O índice de congestão portal foi estatisticamente diferente entre os grupos e os valores para cordeiros, novilhos e ovelhas foram 0,009; 0,058 e 0,09, respectivamente (P<0.01). Observaram-se diferenças estatísticas nos diâmetros da veia porta, na área da veia porta e nos índices de congestão portal entre os grupos, provavelmente devido à influência do peso e não pela idade.(AU)

Doppler hepático na pré-eclâmpsia e na síndrome HELLP / Doppler ultrasonography of the liver in pre-eclampsia and HELLP syndrome

O fígado está entre os múltiplos órgãos que podem ser afetados na pré-eclâmpsia, e a função hepática pode ser gravemente prejudicada na síndrome HELLP. A ultrassonografia com Doppler constitui um método não invasivo que pode ser usado para o estudo da circulação hepática durante a gravidez. Com o objetivo de apresentar as evidências científicas disponíveis sobre as alterações do fluxo hepático na gravidez, foi realizada pesquisa da literatura mundial por meio das bases de dados MEDLINE/PubMed e LILACS. Em estudos de Dopplerfluxometria e Dopplervelocimetria, isoladamente ou associados ao eletrocardiograma e cardiografia por impedância, foram observadas alterações na circulação hepática durante a gravidez complicada por pré?eclâmpsia e síndrome HELLP. Entre os desafios para a pesquisa nesse campo destacamos a necessidade de aperfeiçoamento da técnica de exame, o estabelecimento de curvas de normalidade para as gestantes brasileiras, de indicadores de agravamento da pré?eclâmpsia e a aplicação potencial do método para o estudo da hipertensão crônica na gravidez.(AU)

The liver is among multiple organs that may be affected in pre-eclampsia, and liver function can be impaired in HELLP syndrome. Doppler ultrasonography of the liver provides a noninvasive method to study liver circulation during pregnancy. This paper reviews scientific evidence available in MEDLINE/ Pubmed and LILACS databases. Doppler studies on hepatic blood flow, flow velocities and vascular resistance indices, isolated or combined with Doppler?electrocardiography and impedance cardiography, observed changes in pregnancies complicated by pre?eclampsia and HELLP syndrome. Challenges to this research topic include improvements in Doppler examination techniques, establishment of normal values for Brazilian pregnant women, predictors for severe pre?eclampsia and potential use of hepatic Doppler use in chronic hypertension as well.(AU)

Computed tomography findings of hepatic veno-occlusive disease caused by Sedum aizoon with histopathological correlation

This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.

Derivaciones portosistemáticas congénitas: reporte de caso en un canino / Congenital portosystemics shunts: case report in a dog

Las derivaciones portocava extrahepáticas son anomalías vasculares donde la circulación portal se conecta con la circulación sistemática. En los caninos constituyen el 45% de las anomalías portovasculares, registrándose un predisposición racial. El objetivo de este trabajo es presentar los hallazgos ecográficos en un canino de raza Yorkshire. Se observó disminución del tamaño hepático, con la presencia de un vaso anómalo que comunicaba la vena porta con la vena cava, y donde el Doppler color registró turbulencia. Luego de la corrección quirúrgica, se observó un aumento del diámetro de la vena porta, con aumento del tamaño del órgano. En el diagnóstico de las derivaciones vasculares extra hepáticas, la ecografía tiene la ventaja de ser un método no invasivo que da información sobre el parénquima hepático y la vasculatura, sirviendo de guía para la selección de los procedimientos quirúrgicos.

Resecciones hepáticas sin tecnología de punta: ocho años de experiencia / Liver resection without advanced technologies: eight years experience

Introducción. Las hepatectomías son intervenciones quirúrgicas de gran envergadura. En la mayoría de los centros que las realizan, la tecnología es un importante soporte para su ejecución. El objetivo del estudio fue comparar los resultados obtenidos sin tecnología de última generación con los logrados en centros donde sí se utiliza. Diseño. Es un estudio retrospectivo, observacional y transversal. Se llevó a cabo en la Clínica Sucre, centro privado de tercer nivel. Material y métodos. Se analizaron 72 resecciones hepáticas en 68 pacientes. Los datos recolectados fueron: sexo, edad, enfermedad, tipo de resección practicada, procedimientos quirúrgicos asociados, volumen de sangre transfundida, estadía hospitalaria, morbilidad y mortalidad. La sección parenquimatosa se hizo con una técnica denominada “kellyclasia”. En la superficie de corte se colocó una compresa embebida en solución fisiológica caliente durante unos minutos. Resultados. De las 72 resecciones, 21 fueron mayores; en 19 ocasiones se asoció otro procedimiento quirúrgico. Catorce pacientes tenían cirrosis hepática. Se requirió transfusión de sangre en 26 pacientes, con una media de 807,6 ml, en 6 de los cuales se utilizó la técnica de autotransfusión por hemodilución normovolémica. El tiempo operatorio tuvo una media de 112 minutos. La morbilidad fue de 34,72 % y la mortalidad, de 5,5 %. Conclusión. Los resultados obtenidos son similares a los presentados en diferentes series. La ausencia de tecnología de última generación no es indispensable a la hora de obtener buenos resultados.

Background: Liver resection is a major type of surgery. Advanced technology as used in different centers constitutes an important support for its adequate performance. Aim: To compare our results without the use of advanced technologies with those of centers that have them available. Hypothesis: Technology is not indispensable in liver resection. Setting: Clínica Sucre, a tertiary level of care private Center. Design: Observational retrospective and transverse analysis. Material and methods: 72 hepatectomies performed in 68 patients were analyzed. Sex, age, pathology, type of liver resection, associated procedures, blood transfusion, hospital stay, morbidity and mortality rates were evaluated. Parenchymal section was made with “kellyclasie”. In the transection surface a warm water soaked-up compress was placed for a few minutes. Results: there were 21 major hepatectomies. In 19 opportunities an associate procedure was required. Cirrothic liver was present in 14 patients. Blood transfusion was used in 26 cases (transfusional media 807.6 ml), 6 of them with normovolemic hemodilution. Surgical time showed a media of 112 minutes. Morbidity rate was 34.72 % and mortality rate 5.5 %. Conclusion: Our results are similar to those published by centers that use advanced technology for liver resection.

Malformación de abernethy tipo 1: presentación de un caso clínico y revisión de la literatura / Abernethy Malformation type 1: report of a case and review of the literature

Se presenta caso de preescolar masculino de 5 años con antecedente de hepatoesplenomegalia desde el año de vida, quien consultó con clínica de hematuria, se realizó ecografía abdominal con hallazgos: de imágenes hipoecoicas difusas en el parénquima hepático, dificultad para valorar el sistema porta, esplenomegalia. Eco Doppler del sistema venoso portal presencia de anomalía vascular portal, no se observo porta principal, se realizó Angiotac multicorte del sistema arterial venoso portal y mesenterico que confirmo Agenesia de la vena Porta. Se diagnóstico malformación de Abernethy tipo I. Las malformaciones del sistema venoso abdominal son alteraciones vasculares raras. El primer acontecimiento de la ausencia congénita de la vena porta viene dado por un shunt cava mesenterico, los shunts portocava (SPC), son malformaciones infrecuentes descritas por Abernethy en 1973, se clasifican en dos grupos según la presencia tipo (II) o ausencia de la vena porta tipo (I). La malformación de Abernethy tipo I usualmente se relaciona a otras anomalías congénitas tales como: defectos cardiacos, atresia de vías biliares y poliesplenia, más frecuentes en el sexo femenino; en varones puede no encontrarse anomalías congénitas asociadas.

A case report of male preschool 5 years old with a history of hepatosplenomegaly since life, who consulted with clinical hematuria, abdominal ultrasonography was performed with fi ndings: hypoechoic image in the liver parenchyma diffuse, diffi cult to assess the portal system, splenomegaly. Echo Doppler of the portal venous system, presence of portal vascular anomaly, there was no main portal was ANGIOTAC multislice system portal and mesenteric venous blood confirmed that agenesis of the portal vein. Abernethy malformation is diagnosed type I Malformations of the abdominal venous system are rare vascular abnormalities. The first event of the congenital absence of the portal vein is given by a mesenteric caval shunt, shunts the Portocava (SPC) are rare malformations described by Abernethy in 1973, are classified into two groups according to the present type (II) or absence of portal vein type(I). The Abernethy malformation type I is usually associated with other abnormalities such as heart defects, atresia of bile ducts and poliesplenia more frequent in females, males May be associated congenital anomalies.

Amplio espectro de la enfermedad vascular hepática en imágenes / Ample spectrum of vascular hepatic disease

La enfermedad vascular hepática (EVH)constituye un amplio espectro de entidades de baja prevalencia, pero con manifestaciones clínicas diversas que pueden llevar a la muerte. Una detección temprana y un tratamiento oportuno cambian el pronóstico. De ahí que las imágenes diagnósticas desempeñen un papel fundamental; sin embargo, hay que tener en cuenta el amplio diagnóstico diferencial. La tomografía computarizada de abdomen es una de las herramientas más útiles para el diagnóstico, sin olvidar otros métodos de imagen, como el ultrasonido Doppler y la resonancia magnética. La EVH puede clasificarse según la repercusión que se pueda derivar de ella, por lo que en términos prácticos puede dividirse en alteraciones venosas, portales, arteriales, sinusoidales y otras. El objetivo de esta revisión es describir la presentación más frecuente de la EVH y sus principales hallazgos y diagnósticos diferenciales, al tiempo que se reconoce su correlación con los mecanismos fisiopatológicos.

Hepatic vascular diseases (HVD) are a broad spectrum of entities of low prevalence but with different clinical manifestations that may even lead to death. Its early detection and timely treatment may change the prognosis. Diagnostic imaging plays a key role and imaging findings may be typical.However, in most cases, radiologists must take into account a wide range of differential diagnosis. Computed tomography (CT) of the abdomen is one of the most useful tools for the diagnosis of HVD taking also into account the value of other imaging methods such as Doppler Ultrasound andMagnetic Resonance Imaging (MRI).HVD can be classified according to the compromised vascular structure and can be divided into venous, portal, arterial, sinusoidal and others disorders. The objective of this review is to describe the most common presentation HVD . The major imaging findings and differential diagnosis recognizingits correlation with the pathophysiological mechanisms.

Artéria hepática acessória: incidência e distribuição / Accessory hepatic artery: incidence and distribution

As variações anatômicas das artérias hepáticas são comuns. A identificação pré-operatória dessas variações é importante para prevenir lesão inadvertida e complicações potencialmente letais durante procedimentos abertos e endovasculares. Objetivo: Avaliar a incidência, o trajeto extra-hepático e a presença de ramos laterais das artérias hepáticas acessórias definidas como um suprimento arterial adicional para o fígado na presença de artéria hepática normal. Métodos: Oitenta e quatro cadáveres humanos masculinos foram dissecados através de laparotomia mediana transperitoneal. A aorta supracelíaca, o eixo celíaco e as artérias hepáticas foram dissecados, e suas trajetórias foram identificadas para descrever os padrões dos ramos arteriais...

Anatomic variations of the hepatic arteries are common. Preoperative identification of these variations is important to prevent inadvertent injury and potentially lethal complications during open and endovascular procedures. Objective: To evaluate the incidence, extra-hepatic course, and presence of side branches of accessory hepatic arteries, defined as an additional arterial supply to the liver in the presence of normal hepatic artery. Methods: Eighty-four human male cadavers were dissected using a transperitoneal midline laparotomy. The supra-celiac aorta, celiac axis, and hepatic arteries were dissected, and their trajectories were identified to describe arterial branching...

Portal hypertensive response to kinin

Portal hypertension is the most common complication of chronic liver diseases, such as cirrhosis. The increased intrahepatic vascular resistance seen in hepatic disease is due to changes in cellular architecture and active contraction of stellate cells. In this article, we review the historical aspects of the kallikrein-kinin system, the role of bradykinin in the development of disease, and our main findings regarding the role of this nonapeptide in normal and experimentalmodels of hepatic injury using the isolated rat liver perfusion model (mono and bivascular) and isolated liver cells. We demonstrated that: 1) the increase in intrahepatic vascular resistance induced by bradykinin is mediated by B2 receptors, involving sinusoidal endothelial and stellate cells, and is preserved in the presence of inflammation, fibrosis, and cirrhosis; 2) the hepatic arterial hypertensive response to bradykinin is calcium-independent and mediated by eicosanoids; 3) bradykinin does not have vasodilating effect on the pre-constricted perfused rat liver; and, 4) after exertion of its hypertensive effect, bradykinin is degraded by angiotensin converting enzyme. In conclusion, the hypertensive response to BK is mediated by the B2 receptor in normal and pathological situations. The B1 receptor is expressed more strongly in regenerating and cirrhotic livers, and its role is currently under investigation.

Hipertensão portal é a complicação mais comum das doenças crônicas do fígado, tais como cirrose. A resistência intravascular aumentada observada na doença hepática é devida a alterações na arquitetura celular e contração ativa das células estreladas. Neste trabalho revisamos aspectos históricos do estudo do sistema calicreína-cinina e os resultados de nossos estudos do papel deste nonapeptídeo no controle do tono vascular intra-hepático em condições normais e modelos experimentais de agressão hepática usando a perfusão de fígado isolado de rato (mono e bivascular) e células hepáticas isoladas. Nós demonstramos que: 1) o aumento da resistência vascular intrahepática induzido pela bradicinina é mediado por receptores B2, envolve a participação de células endoteliais sinusoidais e células estreladas e não é alterada pela presença de inflamação, fibrose ou cirrose; 2) a resposta hipertensiva induzida pela bradicinina no sistema arterial hepático é cálcio-independente emediada por eicosanóides; 3) bradicinina não tem efeito dilatador na circulação intra-hepática; 4) após exercer efeito vasoconstritor intra-hepático, a bradicinina é degradada pela enzima conversora de angiotensina. Em conclusão, a resposta hipertensiva à bradicinina é mediada pelo receptor B2 em condições normais e patológicas. Receptor B1 é expresso mais fortemente nos fígados em regeneração e cirróticos e seu papel está sob investigação.

Donador exógeno de óxido nítrico en la respuesta inflamatoria hepática y hemodinámica después de choque hemorrágico / Exogenous nitric oxide donor in the liver inflammatory and hemodynamic response after hemorrhagic shock

BACKGROUND: Hemorrhagic shock (HS) results in oxidative stress to cells and in the induction of the inflammatory response, with an increased expression of a number of proinflammatory mediators and cytokines. We tested the ability of the nitric oxide (NO) donor sodium nitroprusside (NP) to reduce tissue injury in a rodent model of uncontrolled hemorrhagic shock. METHODS: Seventy two Sprague Dawley rats weighing 250-300 g were subjected to a model of uncontrolled hemorrhagic shock. Four groups of animals were included (n = 18 per group): sham/saline, sham/NP, shock/saline, shock/NP. Experimental design consisted of the development of hemorrhagic shock (3 ml/100 g) in a 15-min period, tail amputation (75%) and drug administration at 30 min, fluid resuscitation (FR) with Ringer's lactate (RL) solution to reach a mean arterial pressure (MAP) of 40 mmHg, a hospital phase of 60 min with hemostasis and FR with LR solution to reach a MAP of 70 mmHg, and a 3-day observation phase. Treatment at the beginning of resuscitation included either normal saline (groups 1, 3) or NP (0.5 mg/kg) (groups 2, 4). The following parameters were evaluated: fluid requirements for resuscitation, liver injury tests, liver tissue myeloperoxidase (MPO), liver histology, and 3-day survival. RESULTS: NP significantly reduced fluid requirements for resuscitation (p = 0.0001). We also observed an improved statistically significant difference in tests demonstrating hepatic injury (p = 0.0001), neutrophil infiltration as evidences by liver MPO (p <0.05), and histology studies (p = 0.001). Survival was also increased from 40% in controls to 60% with NP treatment. CONCLUSIONS: These data suggest that excess NO mediates hemorrhage-induced liver injury, and that the suppression of NO with NP may reduce the pathological consequences of severe hemorrhage, possibly by scavenging superoxide (O(2)(-)), thus limiting the production of more aggressive radicals.

Liver histological, portal flow and plasmatic nitric oxide alterations caused by biliary obstruction and drainage in rats / Alterações histológicas, do fluxo portal e do óxido nítrico plasmático em ratos submetidos à obstrução/desobstrução biliar

PURPOSE: To evaluate liver alterations caused by biliary obstruction and drainage. METHODS: Thirty-nine male Wistar rats were randomly distributed in 4 groups: BO (n=18) bile duct ligation for 20 days, with a periodic evaluation of liver histological alterations, Doppler echography portal flow and measurements of NO and malondialdehyde (MDA); BO/DB (n=13) bile duct occlusion for 20 days followed by biliary drainage by choledochoduodenal anastomosis, 5 days follow-up, same BO group parameters evaluations; group CED (n=4) sham operation and portal flow evaluation trough 20 days; CHB (n=4) sham operation, with hepatic biopsy on 25th day and followed-up trough 25 days, by the same parameters of group BO, with exception of portal flow. Direct bilirubin (DB) and alkaline phosphatase (AP) were evaluated in the group BO, BO/DB and CHB. RESULTS: The bile duct ligation led to an increase of DB and AP, development of liver histological alterations, reduction of portal flow and increase of plasmatic NO and of MDA levels. The bile duct clearing resulted in a reduction of DB, AP, NO, MDA histological alterations and increase of portal flow. CONCLUSION: The biliary occlusion resulted in cholestasis and portal flow reduction, besides the increase of plasmatic NO and of hepatic MDA levels, and histological liver alterations, with a tendency of normalization after the bile duct clearing.

OBJETIVO: Avaliar alterações hepáticas resultantes do processo de obstrução/desobstrução biliar. MÉTODOS: Trinta e nove ratos Wistar foram distribuídos aleatoriamente em 4 grupos: OB (n=18), oclusão biliar, seguimento de 20 dias, avaliação das alterações histológicas hepáticas, do fluxo portal e dosagens de NO e de malondialdeído (MDA); grupo OB/DB (n=13) oclusão biliar por 20 dias seguida de desobstrução biliar por anastomose colédoco-duodenal, seguimento por 5 dias e avaliação dos mesmos parâmetros do grupo BO; grupo CED (n=4) operação simulada, avaliação do fluxo portal e seguimento por 25 dias; grupo CHB (n=4) operação simulada com biópsia hepática no 25º dia, e seguido por 25 dias com avaliação periódica dos mesmos parâmetros do grupo BO, com exceção da ecografia Doppler. Nos grupos BO, OB/DB e CHB foram avaliadas também a bilirrubina direta (BD) e a fosfatase alcalina (FA). RESULTADOS: A oclusão do colédoco causou aumento da BD e da FA, desenvolvimento de alterações hepáticas, redução do fluxo portal, com aumentos do NO plasmático e do MDA. A desobstrução biliar resultou na redução da BD, da FA, das alterações hepáticas, aumento do fluxo portal e redução do NO e do MDA. CONCLUSÃO: A obstrução biliar resultou em colestase, alterações histológicas hepáticas, diminuição do fluxo portal, aumentos do NO plasmático e MDA hepático, com tendência à normalização após a desobstrução biliar.

Evaluación de la anatomía arterial hepática en tomografia computada multicorte de rutina / Evaluation of hepatic arterial anatomy in rutinary multislice computed tomography (msct): a preliminary report

Introduction: Multislice computed tomography (MSCT) appears to provide more advantages in the evaluation of abdominal diseases, and particularly in the study of vascular structures. It optimizes the use of I.V. contrast, and offers a greater temporal and spatial resolution, thus allowing a isotropic resolution. Hepatic circulation variants respond to embryologic development. Objectives: To demonstrate that rutinary MSCT studies (not vascular) with I.V. contrast allow us to evaluate hepatic arterial circulation by detecting the most frequent variants in our population. Material and Methods: A retrospective analysis of a rutinary abdominal MSCT with I. V. contrast was conducted from June 2006 to August 2006, at Clinica Indisa, Santiago, Chile. In 100 cases out of 102, we could properly assess the hepatic arterial anatomy. Axial cuts, Multi Planar Reconstruction (MPR), Maximum Intensity Projection (MIP), and 3D images were reviewed for study analysis. As for classification purposes, variants described by Couinaud and Michels were used. Results: The mean age was 57.3 years; 47 percent male and 53 percent female. Type I variant was found in 53 patients (53 percent); 10 type II (10 percent); 10 type III (10 percent); 3 type IV (3 percent); 9 type V (9 percent); 7 type VI (7 percent); 1 type VII (1 percent); 2 type IX (2 percent), and 5 type XI (5 percent). Type VIII and type X variants were not found. Conclusions: Abdominal MSCT with I.V. contrast has proved to be effective in properly evaluating hepatic arterial circulation in rutinary studies. Forty-seven percent (47 percent) of patients presented anatomic variants, which correlates with findings reported in foreign literature. Due to the high frecuency rate of patients with anatomic variation, vascular evaluation has become a must before planning major hepatic surgical procedures.

La tomografía computada multicorte (TCM) ha demostrado ventajas en la evaluación de la patología abdominal y en especial del estudio de estructuras vasculares. Optimiza el uso del contraste endovenoso (EV) y tiene una mayor resolución temporal y espacial, permitiendo una resolución isotrópica. Las variantes de la circulación hepática responden al desarrollo embriológico. Objetivos: Demostrar que estudios rutinarios (no vasculares) de TCM con cte. EV, permiten evaluar la circulación arterial hepática, detectando las variantes más frecuentes en nuestra población. Material y Métodos: Análisis retrospectivo de TCM abdominales con uso de contraste EV, desde el 1/6/06 al 26/8/06, en Clínica Indisa. De un total de 102 pacientes, en 100 fue posible evaluar adecuadamente la anatomía arterial hepática. En el análisis de los estudios se revisaron los cortes axiales, reconstrucciones multiplanares, 3D y con modalidad MIP. Para la clasificación se utilizó las variantes descritas por Couinaud y Michels. Resultados: El promedio de edad fue de 57,3 años; 47 por ciento fueron hombres y 53 por ciento mujeres. En 53 pacientes se pesquisó variante tipo I (53 por ciento), 10 tipo II (10 por ciento), 10 tipo III (10 por ciento), 3 tipo IV (3 por ciento), 9 tipo V(9 por ciento), 7 tipo VI (7 por ciento), 1 tipo Vil (1 por ciento), 2 tipo IX (2 por ciento) y 5 tipo XI (5 por ciento). No se encontraron pacientes con tipo VIII y X. Conclusiones: La TCM abdominal de rutina que utiliza contraste EV permite evaluar adecuadamente la circulación arterial hepática. Un 47 por ciento mostró variantes anatómicas, concordante con publicaciones extranjeras. Debido a la alta frecuencia de variantes de la circulación hepática, se hace necesaria la evaluación vascular al planificar procedimientos quirúrgicos hepáticos mayores.

Remodeling of hepatic vascular changes after specific chemotherapy of schistosomal periportal fibrosis

Hepatosplenic schistosomiasis was the first human disease in which the possibility of extensive long standing hepatic fibrosis being degraded and removed has been demonstrated. When such changes occurred, the main signs of portal hypertension (splenomegaly, esophageal varices) progressively disappeared, implying that a profound vascular remodeling was concomitantly occurring. Hepatic vascular alterations associated with advanced schistosomiasis have already been investigated. Obstruction of the intrahepatic portal vein branches, plus marked angiogenesis and compensatory hyperplasia and hypertrophy of the arterial tree are the main changes present. However, there are no data revealing how these vascular changes behave during the process of fibrosis regression. Here the mouse model of pipestem fibrosis was used in an investigation about these vascular alterations during the course of the infection, and also after treatment and cure of the disease. Animals representing the two polar hepatic forms of the infection were included: (1) "isolated granulomas" characterized by isolated periovular granulomas sparsely distributed throughout the hepatica parenchyma; and (2) 'pipestem fibrosis' with periovular granulomas and fibrosis being concentrated within portal spaces, before and after treatment, were studied by means of histological and vascular injection-corrosion techniques. Instances of widespread portal vein obstruction of several types were commonly found in the livers of the untreated animals. These obstructive lesions were soon repaired, and completely disappeared four months following specific treatment of schistosomiasis. Treatment was accomplished by the simultaneous administration of praziquantel and oxamniquine. The most impressive results were revealed by the technique of injection of colored masses into the portal system, followed by corrosion in strong acid. The vascular lesions of non-treated pipestem fibrosis were represented...

Anatomia das veias hepáticas em doadores e receptores de transplante hepático intervivos / Hepatic veins anatomy of donors and recipients of living related liver transplantation

Anomalias das veias hepáticas são comuns e podem aumentar as complicações do transplante hepático intervivos. Objetivo - avaliar a anatomia das veias hepáticas nos doadores e receptores do transplante hepático intervivos realizados no Hospital de Clínicas da Universida Federal do Paraná e do Hospital Nossa Senhora das Graças de Curitiba / Anomalies of the hepatic veins are common and may increase complications after living related liver transplantation. Aim - to describe the anatomy of the hepatic artery of donors and recipients of living related liver transplantation...

Estudo morfométrico comparando duas alternativas de reconstrução da via de efluxo venoso do enxerto no método piggyback de transplante de fígado / Morphometric study comparing two methods of hepatic venous outflow reconstruction in piggyback liver transplantation

INTRODUÇÃO: No método piggyback de transplante de fígado (Tx), o pinçamento da veia cava inferior (VCI) do receptor é apenas parcial, permitindo a manutenção do retorno venoso durante a fase anepática sem a necessidade de utilização de desvio veno-venoso. A essa vantagem, contrapõe-se uma maior incidência de obstrução da drenagem venosa do enxerto, complicação que está relacionada com o tipo de reconstrução empregado. A implantação da VCI do enxerto no óstio das veias hepáticas média e esquerda (ME) do receptor tem sido evitada devido a uma maior freqüência de bloqueio venoso. Essa incidência diminui quando são empregadas a anastomose látero-lateral (LL) ou a implantação da VCI do enxerto no óstio das veias hepáticas direita, média e esquerda (DME) do receptor. Entretanto, essas reconstruções reduzem a eficiência do retorno venoso na fase anepática do Tx devido à constrição mais pronunciada da VCI durante o pinçamento necessário para a confecção da anastomose. A alternativa de utilizar o óstio formado pelas veias hepáticas direita e média (DM) pode propiciar uma constrição menor da VCI. Entretanto, esse benefício só se justifica se a via de efluxo venoso obtida não apresentar restrições anatômicas. O objetivo deste trabalho é comparar a congruência do perímetro da VCI com o perímetro das bocas anastomóticas e dos óstios de drenagem na VCI, obtidos por meio da utilização das modalidades DM e DME para a reconstrução do efluxo venoso no Tx piggyback. MÉTODO: Foram estudados prospectivamente 16 cadáveres frescos. Após a hepatectomia total, realizou-se o estudo morfométrico da confluência hepatocaval aferindo-se o perímetro da VCI (PVCI) e, nas reconstruções DM e DME, o perímetro das bocas anastomóticas (PDM e PDME) e dos óstios de desembocadura na VCI (PoDM e PoDME). Foram obtidas imagens digitalizadas de todos os perímetros. As medidas foram realizadas por meio do programa analisador de imagens KS300. A análise estatística foi realizada por meio de análise...

INTRODUCTION: In piggyback liver transplantation (LT), partial clamping of the recipient inferior vena cava (IVC) preserves the venous return of the lower extremities during the anhepatic phase precluding the use of venovenous bypass. The incidence of hepatic venous outflow obstruction after piggyback LT varies according to the type of venous reconstruction. Anastomosis between the cranial portion of the graft IVC and common stump of the middle and left hepatic veins (ME) of the recipient has been avoided due to a higher frequency of hepatic venous outflow obstruction. This incidence decreases when a cavo-caval side-to-side anastomosis (SS) or the ostium of the three main hepatic veins of the recipient (RML) are used. On the other hand, venous return is reduced in these modalities due to a more pronounced constriction during the IVC clamping. The use of the ostium formed by the right and middle hepatic veins (RM) may limit IVC constriction. However, this benefit is only justified if a hepatic venous outflow tract with no anatomical restrictions can be obtained. The aim of this study is to compare the congruence of the IVC perimeter with the perimeter of the venous outflow tract at the anastomotic site and also its opening into the IVC both in the RM and RML modalities. METHODS: Sixteen fresh human cadavers were prospectively studied. After total hepatectomy, a morphometric study of the hepatocaval confluence was done by measuring the perimeter of the IVC (IVCP) and, in RM and RML reconstructions, the perimeter of the venous outflow tract at the anastomotic site (RMP and RMLP) and at its opening into the IVC (RMoP and RMLoP). Digital images of all perimeters were obtained. The measurements were accomplished utilizing the KS300 image analysis software. The statistical analysis was performed using analysis of variance (ANOVA) for repeated measures. Statistical significance was established when the p value was less than 0.05. RESULTS: Examinations were...

Pyruvate kinase activation and lipoperoxidation after selective hepatic ischemia in Wistar rats / Ativação da piruvato quinase e lipoperoxidação após isquemia hepática seletiva em ratos Wistar

PURPOSE: Hepatic ischemia and reperfusion can cause several problems in hepatic surgery. The aim of this study was to determine pyruvate kinase activation and lipid peroxidation after hepatic ischemia. METHODS: Twenty-four Wistar rats were submitted to 90 minutes of selective liver ischemia and 15 minutes of reperfusion. Twelve animals were submitted to selective liver ischemia and reperfusion (Group A) and the other 12 were submitted to sham operation (Group B). After 15 minutes of reperfusion, the following parameters were measured: mean arterial pressure (MAP), alanine aminotransferase (ALT), glycemia (GLY), hepatic glycogen (GH), pyruvate kinase (PK) activation, hepatic glutathione (GSH) and malondialdehyde (MDA). Analysis of the results were made by the Student t-test and has been considered significant difference for p<0.05. RESULTS: A and B were differents for all parameters analized. CONCLUSION: The animals of group A showed reperfusion syndrome with a fall in MAP, activation of glycid metabolism through the glycolitic pathway and presence of lipid peroxidation compared to group B.

OBJETIVO: A isquemia e reperfusão hepática podem causar graves repercussões hepatocelulares em cirurgias hepáticas. O objetivo deste estudo foi determinar o comportamento da piruvato EM PORTUGUES quinase e a lipoperoxidação após isquemia hepática. MÉTODOS: Foram utilizados vinte e quatro ratos Wistar machos divididos em dois grupos. Doze animais foram submetidos a 90 minutos de isquemia hepática seletiva e reperfusão hepática de por 15 minutos (pressão arterial média (PAM), alanina aminotransferase (ALT), glicemia (GLI), gicogênio hepático (GH), ativação da piruvato quinase (PQ), glutationa hepática (GSH) e malondialdeído (MDA). Os resultados foram analisados utilizando o teste t de Student sendo as diferenças consideradas significativas para p<0,05. RESULTADOS: Verificou-se diferença significativa entre os grupos em todos os parâmetros analisados. CONCLUSÃO: Verificou-se que os animais do grupo A mostraram síndrome de reperfusão com queda da PAM, ativação do metabolismo da glicose através da via glicolítica e presença de lipoperoxidação quando comparada com o grupo B.

Hepatic microcirculatory failure / Falência microcirculatória hepática

Liver ischemia has been considered a frequent problem in medical practice, and can be associated to a number of surgical and clinical situations, such as massive hepatic resections, sepsis, liver trauma, circulatory shock and liver transplantation. After restoring blood flow, the liver is further subjected to an additional injury more severe than that induced by ischemia. On account of the complexity of mechanisms related to pathophysiology of ischemia and reperfusion (I/R) injury, this review deals with I/R effects on sinusoidal microcirculation, especially when steatosis is present. Alterations in hepatic microcirculation are pointed as a main factor to explain lower tolerance of fatty liver to ischemia-reperfusion insult. The employment of therapeutic strategies that interfere directly with vasoactive mediators (nitric oxide and endothelins) acting on the sinusoidal perfusion seem to be determinant for the protection of the liver parenchyma against I/R. These approaches could be very suitable to take advantage of marginal specimens as fatty livers, in which the microcirculatory disarrangements hamper its employment in liver transplantation.

A isquemia hepática é um problema relativamente freqüente na prática clínica, sobrevindo em situações diversas como ressecções hepáticas maciças, sepse, trauma hepático extenso, choque circulatório e transplante hepático. Durante a restauração do fluxo sanguíneo, o fígado é submetido a uma agressão adicional ainda mais intensa que aquela imposta pela isquemia. Devido à complexidade dos diversos mecanismos envolvidos na fisiopatologia da lesão por isquemia e reperfusão (I/R) hepática, esta revisão se limitará a discorrer sobre os efeitos da I/R na microcirculação sinusoidal, com ênfase para as alterações microvasculares que tomam lugar no fígado esteatótico pós-isquêmico. O desarranjo microcirculatório é apontado como um importante fator para explicar a reduzida tolerância do fígado esteatótico ao insulto isquêmico. O desenvolvimento de estratégias terapêuticas capazes de interferir diretamente com os mediadores vasoativos (óxido nítrico e endotelinas) relacionados ao déficit perfusional será determinante para a proteção do parênquima hepático frente às alterações induzidas pela I/R. Esses recursos seriam de especial interesse para o aproveitamento de fígados marginais, cuja falência microcirculatória compromete sobremaneira sua utilização para o transplante hepático.