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1.
Int J Mol Sci ; 21(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321947

RESUMO

Liver disease resulting from heart failure (HF) has generally been referred as "cardiac hepatopathy". One of its main forms is congestive hepatopathy (CH), which results from passive venous congestion in the setting of chronic right-sided HF. The current spectrum of CH differs from earlier reports with HF, due to ischemic cardiomyopathy and congenital heart disease having surpassed rheumatic valvular disease. The chronic passive congestion leads to sinusoidal hypertension, centrilobular fibrosis, and ultimately, cirrhosis ("cardiac cirrhosis") and hepatocellular carcinoma after several decades of ongoing injury. Contrary to primary liver diseases, in CH, inflammation seems to play no role in the progression of liver fibrosis, bridging fibrosis occurs between central veins to produce a "reversed lobulation" pattern and the performance of non-invasive diagnostic tests of liver fibrosis is poor. Although the clinical picture and prognosis is usually dominated by the underlying heart condition, the improved long-term survival of cardiac patients due to advances in medical and surgical treatments are responsible for the increased number of liver complications in this setting. Eventually, liver disease could become as clinically relevant as cardiac disease and further complicate its management.


Assuntos
Insuficiência Cardíaca/complicações , Hepatopatias/etiologia , Humanos , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Circulação Hepática , Hepatopatias/diagnóstico , Hepatopatias/epidemiologia , Hepatopatias/terapia
2.
Comput Methods Biomech Biomed Engin ; 23(13): 987-1004, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32594768

RESUMO

An image-based numerical algorithm is presented for simulating blood flow through the liver tissue. First, a geometric model is constructed by applying image processing techniques on a real microscopic image of a liver tissue. Then, incompressible blood flow through liver lobules is simulated. Effects of tissue heterogeneity and deformity, presence/absence of the second central vein in a particular lobule, and apparent sinusoids density in the liver cross section on the blood flow are investigated. Numerical results indicate that the existence of thick low permeability vascular septum, high permeability sinusoids, and lobule tissue heterogeneity can considerably affect interlobular and intralobular blood flow.


Assuntos
Processamento de Imagem Assistida por Computador , Circulação Hepática/fisiologia , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Modelos Anatômicos , Análise Numérica Assistida por Computador , Perfusão , Animais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Simulação por Computador , Hemorreologia , Permeabilidade , Reprodutibilidade dos Testes , Suínos
3.
J Vasc Interv Radiol ; 31(7): 1069-1073, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32439249

RESUMO

This report describes a technique for measuring lung shunt fraction (LSF) twice in a single session during planning arteriography for radioembolization using low and standard dose technetium-99m macroaggregated albumin (99mTc-MAA). A patient with a 16.0 cm hepatocellular carcinoma and LSF of 70% was treated with lenvatinib for 4 weeks. Planning arteriography with administration of 0.5 millicuries of 99mTc-MAA was then performed. Arterial access was maintained while the LSF was calculated, which was persistently elevated at 54%. Embolization of arteriovenous shunts was performed during the same session and 5.0 millicuries of 99mTc-MAA were administered. The repeat LSF was 29%. Successful radioembolization was subsequently performed.


Assuntos
Angiografia , Embolização Terapêutica , Circulação Hepática , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Circulação Pulmonar , Compostos Radiofarmacêuticos/administração & dosagem , Agregado de Albumina Marcado com Tecnécio Tc 99m/administração & dosagem , Idoso , Humanos , Neoplasias Hepáticas/fisiopatologia , Masculino , Valor Preditivo dos Testes , Resultado do Tratamento
4.
Surgery ; 168(1): 33-39, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32268937

RESUMO

BACKGROUND: Transjugular intrahepatic portosystemic shunt has been established as an effective treatment for complicated portal hypertension. This retrospective study investigated the effect of pretransplant transjugular intrahepatic portosystemic shunt placement on intraoperative graft hemodynamics and surgical outcomes after liver transplantation. METHODS: Of 1,081 patients who underwent liver transplantation between January 2007 and June 2017 at Cleveland Clinic (OH, USA), 130 patients had transjugular intrahepatic portosystemic shunt placement before liver transplant. We performed a 1:2 propensity score matching to compare intraoperative graft hemodynamics and surgical outcomes between the transjugular intrahepatic portosystemic shunt group (n = 130) and the no-transjugular intrahepatic portosystemic shunt group (n = 260). RESULTS: The transjugular intrahepatic portosystemic shunt did not increase operative time, the volume of blood transfusion, duration of hospital stay, or complication rates. Graft and patient survivals were similar between the groups. Mean intraoperative cardiac output and graft portal flow in the transjugular intrahepatic portosystemic shunt group were greater than in the no-transjugular intrahepatic portosystemic shunt group (P = .03 and P = .003, respectively). In multivariate analysis, male sex, younger age, low platelet count, absence of portal vein thrombosis, and pretransplant transjugular intrahepatic portosystemic shunt placement were independently associated with increased portal flow volume (P < or = 0.03 each). Transjugular intrahepatic portosystemic shunt malposition was observed in 17 patients (13.1%). The 1-year patient survival was 70.6% with transjugular intrahepatic portosystemic shunt malposition and 92.0% without transjugular intrahepatic portosystemic shunt malposition (P = .01). CONCLUSION: Our findings suggest that pretransplant transjugular intrahepatic portosystemic shunt placement increases graft portal flow but does not compromise surgical outcomes after liver transplantation. Transjugular intrahepatic portosystemic shunt malposition, however, is not uncommon and may increase the complexity of transplantation.


Assuntos
Transplante de Fígado/mortalidade , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Complicações Pós-Operatórias/etiologia , Idoso , Feminino , Sobrevivência de Enxerto , Humanos , Circulação Hepática , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Derivação Portossistêmica Transjugular Intra-Hepática/estatística & dados numéricos , Pontuação de Propensão , Estudos Retrospectivos
5.
Transplant Proc ; 52(5): 1608-1610, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32241639

RESUMO

INTRODUCTION: Toxic acute liver failure can be fatal even after liver transplantation. Since there are data only in young rats, the aim of our study was to verify the effectiveness of the increase of oxygen to the liver by partial portal vein arterialization (PPVA) in elderly rats with acute liver failure induced by carbon tetrachloride (CCl4) intoxication. METHODS: Twenty elderly (30 months) Sprague-Dawley rats underwent a CCl4 intoxication (5 mL/kg). Animals were divided after 24 hours (n = 10 per group) to either undergo PPVA (G1, treated group) or be untreated (G2, control group). PPVA consisted of a shunt between the left renal artery and splenic vein after nephrectomy and spelnectomy. The G2 group animals underwent nephrectomy and splenectomy only. The 10-day survival was evaluated. Before euthanasia, blood samples from the portal vein were detected for blood gas analysis. Liver injury was evaluated by the serum alanine aminotransferase (ALT) and prothrombin time levels. Histology was done to evaluate the liver necrosis. Hepatocyte regeneration was assessed by the mitotic index at immunohistochemistry. RESULTS: The PPVA has resulted in a significant increase in the oxygen partial pressure and saturation in portal blood. A survival improvement at 10 days was registered in the PPVA-treated rats (90% vs 30%; P = .0065). After 24 hours from intoxication, ALT was high in both groups. A rapid decrease of ALT was observed in G1 as compared to G2. At the same time, livers showed a severe centrolobular necrosis. In the suviving G2 rats, a moderate necrosis was present, while only a mild necrosis was observed in the G1 rats. An higher mitotic index was detected in rats treated with PPVA. CONCLUSIONS: In our experimental study, the presence of oxygenated blood in the portal venous system following the PPVA procedure had positive effects on liver regeneration and rats' survival. The PPVA treatment had beneficial effects in elderly rats.


Assuntos
Derivação Arteriovenosa Cirúrgica , Falência Hepática Aguda/cirurgia , Veia Porta/cirurgia , Artéria Renal/cirurgia , Alanina Transaminase/sangue , Animais , Modelos Animais de Doenças , Fígado/irrigação sanguínea , Circulação Hepática , Falência Hepática Aguda/etiologia , Regeneração Hepática , Transplante de Fígado , Masculino , Oxigênio/sangue , Tempo de Protrombina , Ratos , Ratos Sprague-Dawley
6.
J Vasc Interv Radiol ; 31(10): 1691-1696.e1, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32178944

RESUMO

PURPOSE: To characterize the effect of hepatic vessel flow using 4-dimensional (4D) flow magnetic resonance (MR) imaging and correlate their effect on microwave ablation volumes in an in vivo non-cirrhotic porcine liver model. MATERIALS AND METHODS: Microwave ablation antennas were placed under ultrasound guidance in each liver lobe of swine (n = 3 in each animal) for a total of 9 ablations. Pre- and post-ablation 4D flow MR imaging was acquired to quantify flow changes in the hepatic vasculature. Flow measurements, along with encompassed vessel size and vessel-antenna spacing, were then correlated with final ablation volume from segmented MR images. RESULTS: The linear regression model demonstrated that the preablation measurement of encompassed hepatic vein size (ß = -0.80 ± 0.25, 95% confidence interval [CI] -1.15 to -0.22; P = .02) was significantly correlated to final ablation zone volume. The addition of hepatic vein flow rate found via 4D flow MRI (ß = -0.83 ± 0.65, 95% CI -2.50 to 0.84; P = .26), and distance from antenna to hepatic vein (ß = 0.26 ± 0.26, 95% CI -0.40 to 0.92; P = .36) improved the model accuracy but not significantly so (multivariate adjusted R2 = 0.70 vs univariate (vessel size) adjusted R2 = 0.63, P = .24). CONCLUSIONS: Hepatic vein size in an encompassed ablation zone was found to be significantly correlated with final ablation zone volume. Although the univariate 4D flow MR imaging-acquired measurements alone were not found to be statistically significant, its addition to hepatic vein size improved the accuracy of the ablation volume regression model. Pre-ablation 4D flow MR imaging of the liver may assist in prospectively optimizing thermal ablation treatment.


Assuntos
Técnicas de Ablação , Veias Hepáticas/diagnóstico por imagem , Circulação Hepática , Fígado/irrigação sanguínea , Fígado/cirurgia , Imagem Cinética por Ressonância Magnética , Micro-Ondas , Imagem de Perfusão/métodos , Animais , Velocidade do Fluxo Sanguíneo , Estudos de Viabilidade , Veias Hepáticas/fisiopatologia , Modelos Animais , Valor Preditivo dos Testes , Sus scrofa
7.
Intern Med ; 59(4): 471-477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32062622

RESUMO

Objective The usefulness of contrast-enhanced ultrasonography (CEUS) for making decisions in the treatment of liver abscess is unknown. Methods We evaluated the internal blood flow in the arterial-predominant phase by CEUS using Sonazoid® in 21 patients. The stain area rate was evaluated in maximum parting plane of abscess in CEUS. Patients were divided into two groups: the vascular phase enhancement (VE) group, in which ≥50% of the abscess cavity was enhanced (12 patients), and the vascular phase non-enhancement (VNE) group, in which <50% of the abscess cavity was enhanced (9 patients). The rate of patients who were cured by conservative treatment alone was examined in both groups. The defect rate of all liver abscesses in the post-vascular phase was also evaluated. Results In the VE group, improvement by conservative treatment alone was obtained in 11 out of 12 patients (91.7%), while in the VNE group, improvement by conservative treatment alone was obtained in only 1 out of 9 patients (11.1%), a significant difference (p<0.001). In the VE group, one patient did not improve with conservative treatment alone because the abscess ruptured near the liver surface. In the VE group, the abscess size was smaller than in the VNE group. By examining the defect rate in the post-vascular phase, it was found that 16 out of 21 patients (76.2%) showed 71% or more defects. Conclusion The enhancement rate in the arterial-predominant phase of CEUS was considered useful for determining the treatment approach for liver abscess.


Assuntos
Meios de Contraste/administração & dosagem , Compostos Férricos/administração & dosagem , Ferro/administração & dosagem , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/terapia , Circulação Hepática/fisiologia , Óxidos/administração & dosagem , Ultrassonografia/métodos , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Eur Radiol ; 30(6): 3161-3167, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32048036

RESUMO

OBJECTIVES: To evaluate the implications of hepatic subcapsular and capsular flows using ultrasonography (US) in children after Kasai operation. METHODS: Children who underwent liver US including color Doppler US and microvascular imaging (MVI) from May 2017 to October 2017 were retrospectively included. Children who underwent the Kasai operation for biliary atresia were included in the Kasai group and children with normal liver were included in the control group. Using US results, the number of intrahepatic biliary cysts and the maximum diameter of the spleen were evaluated in the Kasai group. Liver stiffness values were included when patients in the Kasai group had transient elastography (TE) or shear wave elastography (SWE) results. Hepatic subcapsular and capsular flows on color Doppler US and MVI were compared between the two groups using the following scores: 0, no flow reaching the hepatic capsule; 1, any flow reaching the hepatic capsule; and 2, contiguous hepatic capsular flow. The logistic regression test was used to identify associations between age, intrahepatic biliary cysts, spleen size, SWV, TE results, and flow scores measured on Doppler US and MVI in the Kasai group using the odds ratio (OR) and 95% confidence interval (CI). RESULT: A total of 65 children (mean 7.6 ± 5.3 years), 44 in the Kasai group and 21 in the control group, were included. In the control group, one child had score 1 on MVI and others had score 0 on both Doppler US and MVI. Among the Kasai group, 28 children (63.6%) had score 1, while others had score 0 using Doppler US. Using MVI, 24 children (54.5%) had score 2, 18 children had score 1, and one child had score 0. In the Kasai group, increased liver stiffness on TE was the only factor significantly associated with the presence of subcapsular flow on color Doppler US (OR 1.225, 95% CI 1.020-1.470) and increased spleen size was the only factor significantly associated with increased flow scores on MVI (OR 1.397, 95% CI 1.002-2.724). CONCLUSION: Detection of hepatic subcapsular, capsular flows on US would be meaningful for children after receiving the Kasai operation. KEY POINTS: • Hepatic subcapsular or capsular flows can be useful not only for the diagnosis but also for the postoperative follow-up in patients with biliary atresia. • Increased liver stiffness and splenomegaly after the Kasai operation were associated with presence of subcapsular or capsular flow on ultrasonography. • Evaluation of hepatic subcapsular and capsular flows could be needed to assess disease progression after receiving the Kasai operation.


Assuntos
Atresia Biliar/fisiopatologia , Atresia Biliar/cirurgia , Circulação Hepática , Microcirculação , Doenças dos Ductos Biliares/complicações , Doenças dos Ductos Biliares/diagnóstico por imagem , Atresia Biliar/complicações , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Criança , Pré-Escolar , Cistos/complicações , Cistos/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Baço/diagnóstico por imagem , Esplenomegalia , Ultrassonografia Doppler em Cores
9.
J Vasc Interv Radiol ; 31(5): 788-794, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32107126

RESUMO

PURPOSE: To assess the utility of preoperative venography in evaluating and managing patients with congenital portosystemic shunts (CPSSs). MATERIALS AND METHODS: A retrospective study was performed of 42 patients (62% female; median age, 4.1 years) diagnosed with a CPSS from 2005 to 2018. Preoperative venography (n = 39) and balloon occlusive pressure measurements (n = 33) within the mesenteric venous system guided treatment. Primary outcome was serum ammonia levels at 1 month after shunt closure. Management strategies included single (n = 12) or staged (n = 18) operative ligation, endovascular occlusion (n = 8), combined surgical and endovascular closure (n = 2), and observation (n = 2). RESULTS: At 1 month, serum ammonia levels decreased from 82.5 ± 10.3 µmol/L to 38.4 ± 4.6 µmol/L (P < .001). No difference was observed in the decrease between patients treated surgically or endovascularly (P = .91). Mean occluded to non-occluded pressure gradients were significantly lower for endovascular closure (5.3 ± 1.8 mmHg) than for surgical closure (12.3 ± 3.3 mmHg, P = .02). Shunts were classified as extrahepatic in 29 patients and as intrahepatic in 13 patients; all shunts demonstrated filling of the portal system with occlusive venography. Broad and short shunts were closed surgically; narrow and long shunts were closed endovascularly. Shunts were closed in a single session (n = 20) if the pressure gradient was less than 10 mmHg and the occluded mesenteric pressure was less than 25 mmHg. CONCLUSIONS: Preoperative venography delineates shunt morphology, and balloon occlusion simulates closure hemodynamics. This information is necessary to determine whether definitive closure should be performed through endovascular or surgical methods and whether closure should be performed in a single or staged setting.


Assuntos
Flebografia , Veia Porta/diagnóstico por imagem , Veia Porta/cirurgia , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/cirurgia , Procedimentos Cirúrgicos Vasculares , Adolescente , Criança , Pré-Escolar , Bases de Dados Factuais , Procedimentos Endovasculares , Feminino , Humanos , Lactente , Recém-Nascido , Ligadura , Circulação Hepática , Masculino , Pressão na Veia Porta , Veia Porta/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Malformações Vasculares/fisiopatologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Adulto Jovem
10.
Am J Gastroenterol ; 115(1): 18-40, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31895720

RESUMO

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.


Assuntos
Gastroenterologia , Circulação Hepática , Hepatopatias/etiologia , Guias de Prática Clínica como Assunto , Circulação Esplâncnica , Doenças Vasculares/terapia , Humanos , Fígado/irrigação sanguínea , Hepatopatias/fisiopatologia , Mesentério/irrigação sanguínea , Sociedades Médicas , Estados Unidos , Doenças Vasculares/complicações
11.
Am. j. gastroenterol ; 115(1): [18-40], Jan. 2020.
Artigo em Inglês | LILACS | ID: biblio-1117167

RESUMO

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.


Assuntos
Humanos , Circulação Esplâncnica/fisiologia , Administração dos Cuidados ao Paciente/organização & administração , Falência Hepática Aguda/complicações , Circulação Hepática
12.
J Vasc Interv Radiol ; 31(2): 341-346, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759866

RESUMO

PURPOSE: To evaluate feasibility of changing intra-arterial flow direction by temporary occlusion using retrievable coils. MATERIALS AND METHODS: In 2 healthy pig livers, injection of a lipiodol mixture (lipiodol:saline = 2:1) was performed at the segmental arteries after occluding 1 of the subsegmental arteries. This was accomplished using a retrievable coil in 5 different segmental arteries (3 in pig A and 2 in pig B). Injection of the lipiodol mixture was performed through a 3-way system using a hemostatic valve, whereas the retrievable coil delivery system was in the lumen of a microcatheter. Successful coil deployment, occlusion of the vessel, and coil retrieval were evaluated. Redistribution of flow after placement of the coil and vessel patency after coil removal were angiographically evaluated. The distribution of lipiodol mixture was evaluated using cone beam computed tomography. RESULTS: All 5 of the retrievable coils were successfully deployed and removed. Angiography revealed successful occlusion of subsegmental artery after coil placement with flow redistribution followed by restoration of flow after coil retrieval in all cases. On cone beam computed tomography, lipiodol tagging was abundant in hepatic parenchyma supplied by the hepatic artery without coils compared with that supplied by the branch with coils. CONCLUSIONS: Temporary arterial flow redistribution using a retrievable coil was feasible in the healthy pig model and could be applicable for endovascular procedures in which superselection is difficult or unavailable.


Assuntos
Embolização Terapêutica/instrumentação , Artéria Hepática/fisiologia , Circulação Hepática , Fígado/irrigação sanguínea , Animais , Estudos de Viabilidade , Artéria Hepática/diagnóstico por imagem , Modelos Animais , Sus scrofa , Fatores de Tempo , Grau de Desobstrução Vascular
13.
Transplantation ; 104(4): 770-778, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31568395

RESUMO

BACKGROUND: While portal flow (PF) plays an important role in determining graft outcomes in living donor liver transplantation, its impact in deceased donor liver transplantation (DDLT) is unclear. The aim of this study was to investigate the correlations between graft PF and graft outcomes in DDLT. METHODS: We retrospectively investigated 1001 patients who underwent DDLT between January 2007 and June 2017 at our institution. The patients were divided into 3 groups according to hazard ratio for 1-year graft loss at each PF value, which was standardized with graft weight. Graft and recipient outcomes were compared between the groups. RESULTS: The low-PF group (PF < 65 mL/min/100 g, n = 210, P = 0.011) and the high-PF group (PF ≥ 155 mL/min/100 g, n = 159, P = 0.018) showed significantly poorer 1-year graft survival compared with the intermediate-PF group (PF ≥ 65 mL/min/100 g and < 155 mL/min/100 g, n = 632). The patients in the low-PF group had severe reperfusion injury and were more frequently complicated with primary nonfunction (P = 0.013) and early allograft dysfunction (P < 0.001) compared with the other groups. In contrast, the patients in the high-PF group had milder reperfusion injury, but had lower intraoperative hepatic artery flow with higher incidence of hepatic artery thrombosis (P = 0.043) and biliary complication (P = 0.041) compared with the other groups. CONCLUSIONS: These results suggest that intraoperative PF plays an important role in determining early graft outcomes after DDLT.


Assuntos
Hemodinâmica , Circulação Hepática , Transplante de Fígado , Veia Porta/transplante , Adulto , Idoso , Doenças Biliares/etiologia , Doenças Biliares/fisiopatologia , Velocidade do Fluxo Sanguíneo , Feminino , Sobrevivência de Enxerto , Artéria Hepática/fisiopatologia , Humanos , Período Intraoperatório , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Veia Porta/diagnóstico por imagem , Veia Porta/fisiopatologia , Disfunção Primária do Enxerto/etiologia , Disfunção Primária do Enxerto/fisiopatologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Trombose/etiologia , Trombose/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
15.
Surg Today ; 50(1): 21-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31555908

RESUMO

Small-for-size graft (SFSG) syndrome after living donor liver transplantation (LDLT) is the dysfunction of a small graft, characterized by coagulopathy, cholestasis, ascites, and encephalopathy. It is a serious complication of LDLT and usually triggered by excessive portal flow transmitted to the allograft in the postperfusion setting, resulting in sinusoidal congestion and hemorrhage. Portal overflow injures the liver directly through nutrient excess, endothelial activation, and sinusoidal shear stress, and indirectly through arterial vasoconstriction. These conditions may be attenuated with portal flow modulation. Attempts have been made to control excessive portal flow to the SFSG, including simultaneous splenectomy, splenic artery ligation, hemi-portocaval shunt, and pharmacological manipulation, with positive outcomes. Currently, a donor liver is considered a SFSG when the graft-to-recipient weight ratio is less than 0.8 or the ratio of the graft volume to the standard liver volume is less than 40%. A strategy for transplanting SFSG safely into recipients and avoiding extensive surgery in the living donor could effectively address the donor shortage. We review the literature and assess our current knowledge of and strategies for portal flow modulation in LDLT.


Assuntos
Circulação Hepática , Transplante de Fígado/métodos , Fígado/irrigação sanguínea , Doadores Vivos , Veia Porta/fisiopatologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Esplenectomia , Transtornos da Coagulação Sanguínea , Encefalopatias/etiologia , Encefalopatias/terapia , Colestase/etiologia , Colestase/terapia , Humanos , Ligadura , Tamanho do Órgão , Artéria Esplênica/cirurgia , Síndrome
16.
Ann Transplant ; 24: 631-638, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31831725

RESUMO

BACKGROUND Post-reperfusion syndrome (PRS) during liver transplantation can range from a benign event to a profound hemodynamic excursion from baseline with significant morbidity. Multiple variables can be responsible for the diverse presentations. Over time, our group noticed that a blood flush of the liver graft via a caval vent (in addition to a standard chilled flush via the portal vein) appeared to result in a milder reperfusion effect. Attenuation of PRS via caval vent seemed to minimize hemodynamic instability and reduce metabolic derangements associated with reperfusion. MATERIAL AND METHODS This was a prospective observational pilot study of standard practice with the addition of lab values and hemodynamic evaluations. We methodically observed normal clinical flow in 20 adult orthotopic liver transplant recipients. We analyzed blood and fluid samples at set time intervals during the peri-reperfusion phase. RESULTS Sixteen out of 20 patients received a blood flush via caval venting. Mean arterial pressure (MAP) and heart rate were better preserved in the patient population that received a caval blood flush vent. Elevations in central venous pressure (CVP) were similar between the 2 groups. Lab values (blood gas, electrolyte, and hemoglobin) of the patients' blood were similar, with no notable differences. Analysis of the initial blood flushed through the liver graft proved to be hypothermic, acidotic, and hyperkalemic. CONCLUSIONS Pre-reperfusion caval venting in liver transplantation (in addition to a portal vent and a chilled LR/albumin portal flush solution) appears to have favorable hemodynamic effects. The literature on this technique is sparse and larger studies are needed.


Assuntos
Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/prevenção & controle , Idoso , Pressão Sanguínea , Pressão Venosa Central , Feminino , Frequência Cardíaca , Hemodinâmica , Humanos , Fígado/irrigação sanguínea , Circulação Hepática , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Veia Porta , Estudos Prospectivos , Reperfusão/efeitos adversos , Reperfusão/métodos , Traumatismo por Reperfusão/fisiopatologia , Síndrome , Veias Cavas
18.
Clin Transplant ; 33(11): e13723, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31583762

RESUMO

OBJECTIVE: Portal vein thrombosis (PVT) does not preclude liver transplantation (LT), but poor portal vein (PV) flow after LT remains a predictor of poor outcomes. Given the physiologic tendency of the hepatic artery (HA) to compensate for low PV flow via vasodilation, we investigated whether adequate HA flow would have a favorable prognostic impact among patients with low PV flow following LT. METHODS: This study included 163 patients with PVT who underwent LT between 2004 and 2015. PV and HA flow were categorized into quartiles, and their association with 1-year graft survival (GS) and biliary complication rates was assessed. For both the HA and the PV, patients at the lowest two quartiles were categorized as having low flow and the remainder as having high flow. RESULTS: The median MELD score was 22 and 1-year GS was 87.3%. As expected, GS paralleled PV flow with patients at the lowest flow quartile faring the worst. In combination of PV and HA flows, high HA flow was associated with improved 1-year GS among patients with low PV flow (P = .03). Similar findings were observed with respect to biliary complication rates. CONCLUSIONS: Sufficient HA flow may compensate for poor PV flow. Consequently, meticulous HA reconstruction may be central to achieving optimal outcomes in PVT cases.


Assuntos
Artéria Hepática/fisiopatologia , Hepatopatias/mortalidade , Transplante de Fígado/mortalidade , Fígado/irrigação sanguínea , Veia Porta/patologia , Trombose Venosa/mortalidade , Adulto , Idoso , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Circulação Hepática , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Trombose Venosa/fisiopatologia
19.
Cells ; 8(11)2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31653030

RESUMO

Hepatic fibrosis is the consequence of an unresolved wound healing process in response to chronic liver injury and involves multiple cell types and molecular mechanisms. The hepatic endocannabinoid and apelin systems are two signalling pathways with a substantial role in the liver fibrosis pathophysiology-both are upregulated in patients with advanced liver disease. Endogenous cannabinoids are lipid-signalling molecules derived from arachidonic acid involved in the pathogenesis of cardiovascular dysfunction, portal hypertension, liver fibrosis, and other processes associated with hepatic disease through their interactions with the CB1 and CB2 receptors. Apelin is a peptide that participates in cardiovascular and renal functions, inflammation, angiogenesis, and hepatic fibrosis through its interaction with the APJ receptor. The endocannabinoid and apelin systems are two of the multiple cell-signalling pathways involved in the transformation of quiescent hepatic stellate cells into myofibroblast like cells, the main matrix-producing cells in liver fibrosis. The mechanisms underlying the control of hepatic stellate cell activity are coincident despite the marked dissimilarities between the endocannabinoid and apelin signalling pathways. This review discusses the current understanding of the molecular and cellular mechanisms by which the hepatic endocannabinoid and apelin systems play a significant role in the pathophysiology of liver fibrosis.


Assuntos
Apelina/metabolismo , Endocanabinoides/metabolismo , Cirrose Hepática/patologia , Fígado/metabolismo , Proteínas de Transporte/metabolismo , Circulação Êntero-Hepática/fisiologia , Fibrose , Humanos , Hipertensão Portal , Inflamação/patologia , Fígado/patologia , Circulação Hepática/fisiologia , Sistema Porta/fisiologia
20.
Int J Numer Method Biomed Eng ; 35(9): e3229, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31368204

RESUMO

Liver structures of a healthy subject are digitised and segmented from computed tomography (CT) images, and hepatic perfusion is modelled in the hepatic artery and portal vein of the healthy subject with structured tree-based outflow boundary conditions. This self-similar structured tree is widely used in the literature, eg, blood flow simulation in larger systemic arteries and cerebral circulation, and is used in this study to model the effect of the smaller hepatic arteries and arterioles, as well as the smaller hepatic portal veins and portal venules. Physiologically reasonable results are obtained. Since the structured tree terminates at the size of the microvasculature system in liver lobules, the structured tree boundary condition will enable the proposed organ-level model of hepatic arterial flow to be easily connected to tissue-level models of liver lobules. Blood flow in the hepatic vein is also modelled in this subject with three-element Windkessel model as outflow boundary conditions. The benefit of integrating the perfusion in all hepatic vascular vessels is that it helps us analyse some complicated clinical phenomenon more efficiently, eg, one possible application is to obtain the portal pressure gradient (PPG) to help examine the reliability of hepatic venous pressure gradient (HVPG) as an indirect measure of portal pressure. Moreover, since four to six generations of hepatic vessels, which are sufficient for liver classification analysis, were employed in the model, this study is setting the computational foundation of a potentially handy surgical tool.


Assuntos
Circulação Hepática/fisiologia , Modelos Cardiovasculares , Engenharia Biomédica , Simulação por Computador , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/fisiologia , Veias Hepáticas/diagnóstico por imagem , Veias Hepáticas/fisiologia , Humanos , Hidrodinâmica , Imageamento Tridimensional , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Imagem por Ressonância Magnética , Modelos Anatômicos , Pressão na Veia Porta/fisiologia , Veia Porta/diagnóstico por imagem , Veia Porta/fisiologia , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler em Cores
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