Hemodynamics and hepatic energy metabolism in canine model of acute hepatic venous occlusion with mesocaval shunt

Budd-Chiari syndrome: consensus guidance of the Asian Pacific Association for the study of the liver (APASL)

Budd Chiari syndrome (BCS) is a diverse disease with regard to the site of obstruction, the predisposing thrombophilic disorders and clinical presentation across the Asia-Pacific region. The hepatic vein ostial stenosis and short segment thrombosis are common in some parts of Asia-Pacific region, while membranous obstruction of the vena cava is common in some and complete thrombosis of hepatic veins in others. Prevalence of myeloproliferative neoplasms and other thrombophilic disorders in BCS varies from region to region and with different sites of obstruction. This heterogeneity also raises several issues and dilemmas in evaluation and approach to management of a patient with BCS. The opportunity to recanalize hepatic vein in patients with hepatic vein ostial stenosis or inferior vena cava stenting or pasty among those membranous obstruction of the vena cava is a unique opportunity in the Asia-Pacific region to restore hepatic outflow closely mimicking physiology. In order to address these issues arising out of the diversity as well as the unique features in the region, the Asia Pacific Association for Study of Liver has formulated these guidelines for clinicians.

Computed tomography angiography manifestations of collateral circulations in Budd-Chiari syndrome

The aim of this study was to assess the computed tomography angiography (CTA) manifestations of collateral circulations in patients with Budd-Chiari syndrome (BCS). Eighty patients with BCS were examined by CT scan. Using the CTA images of the relevant blood vessels, including the affected hepatic veins (HVs) and inferior venae cavae (IVCs), the collateral circulations were reconstructed. In addition to obstructed HVs and IVCs, collateral circulations were found in each of the patients. The collateral circulations were classified as intrahepatic, extrahepatic and portosystemic pathways. Intrahepatic collateral pathways were further classified as the following six types: HV-accessory HV (n=51, 63.8%), HV-HV (n=6, 7.5%), HV-accessory HV plus HV (n=6, 7.5%), IVC-HV/accessory HV-HV-right atrium (n=5, 6.3%), HV-umbilical vein (n=4, 5.0%) and HV-inferior phrenic vein (n=8, 10.0%). Extrahepatic collateral pathways included IVC-lumbar-ascending lumbar-hemiazygos/azygos vein (n=80, 100.0%), IVC-left renal-ascending lumbar-hemiazygos vein (n=75, 93.8%), IVC-left renal-inferior phrenic vein (n=49, 61.3%), IVC-renal -peri-renal -superficial epigastric vein (n=26, 32.5%) and superficial epigastric vein (n=12, 15.0%) types. The CTA characteristics of each type of collateral circulation were demonstrated. In conclusion, the present study revealed that CTA is able to show the intra- and extrahepatic collateral circulations of patients with BCS, which may be useful for therapeutic planning.

Necessity and indications of invasive treatment for Budd-Chiari syndrome

BACKGROUND

The development of collaterals in Budd-Chiari syndrome has been described and these collaterals play an important role in the presentation of this disease. These collaterals are diagnostic and their use in management strategy has never been evaluated. This study aimed to investigate the indications, feasibility and necessity of invasive treatment for patients with Budd-Chiari syndrome and to determine whether such a strategy is necessary for optimal management.

METHODS

Twenty-nine patients who had been treated at our unit were enrolled in this study. Based on physical and biochemical examination, and hemodynamic compensation by collaterals, 18 patients underwent radiological intervention (group A), while the other 11 had no invasive treatment (group B). The related hemodynamic parameters were acquired when percutaneous angiography was performed.

RESULTS

In group A, all patients underwent successfully inferior vena cava (IVC) balloon angioplasty with or without stenting. Four patients also underwent hepatic vein angioplasty. In these patients, the mean IVC pressure before and after treatment was statistically different (29.3+/-9.2 vs 15.1+/-4.6 mmHg, P<0.01). The mean IVC pressure was much lower in group B than in group A (12.9+/-2.4 vs 29.3+/-9.2 mmHg, P<0.01), but there was no difference from that of the patients after radiological treatment (12.9+/-2.4 vs 15.1+/-4.6 mmHg, P>0.05). Median follow-up was 32.3 months (mean 21.3 months; range 3-61 months). In the course of follow-up, the patients in group A survived with good systemic status except for re-stenosis in one patient who underwent re-canalization of the IVC. In group B, 10 patients had good systemic status except one patient who had a meso-caval shunt because of deterioration.

CONCLUSIONS

The rationale of "early diagnosis and early treatment" is not suitable for all patients with Budd-Chiari syndrome. Satisfactory survival can be achieved in some patients without invasive treatment, who are completely compensated by rich collaterals. Nonetheless, a positive treatment procedure should be performed if the patient's situation worsens in the course of regular follow-up.

CT, MRI, and US findings of incidental segmental distal hepatic vein occlusion: a new form of Budd-Chiari syndrome?

OBJECTIVE

We aimed to describe radiological findings of patients with incidentally diagnosed segmental distal hepatic vein occlusion on computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We retrospectively reviewed CT (n = 8), color Doppler US (n = 6), and MRI (n = 3) findings of 9 patients with incidentally diagnosed segmental occlusion of the hepatic veins from our archive. Computed tomography and US examinations were performed in 4 patients; only CT in 2; US, CT, and MRI in 1; US and MRI in 1; and CT and MRI in 1 patient. Liver contour, presence, and location of hepatico-hepatic shunts were evaluated.

RESULTS

Middle hepatic vein (n = 6) was the most commonly segmentally occluded vein, followed by left hepatic vein (n = 3). Mean length of segmental occlusion was 1.9 cm (range, 1.2-4.2 cm). Hepatico-hepatic shunts were found close to hepatic vein confluence in all but 1 patient. Segmental distal hepatic vein occlusion can cause antegrade (n = 5) or retrograde (n = 1) flow in the affected vein on color Doppler examination, depending on presence of intraparenchymal hepatico-hepatic shunt. In the patient with retrograde flow, occluded segment was very short, and no intraparenchymal shunt was visible. Patients were asymptomatic, and no change in liver morphology (including caudate lobe hypertrophy) was noted.

CONCLUSIONS

We propose that segmental Budd-Chiari syndrome can be a valid terminology for asymptomatic patients with segmental hepatic vein occlusion most likely developing as a sequela of subclinical Budd-Chiari syndrome. Acquaintance of practicing radiologists to this phenomenon may be highly useful in the prevention of the diagnostic confusion and potentially unnecessary interventions.

Budd-Chiari syndrome: Etiology, pathogenesis and diagnosis

Budd-Chiari syndrome is a congestive hepatopathy caused by blockage of hepatic veins. This syndrome occurs in 1/100 000 in the general population. Hypercoagulable state could be identified in 75% of the patients; more than one etiologic factor may play a role in 25% of the patients. Primary myeloproliferative diseases are the leading cause of the disease. Two of the hepatic veins must be blocked for clinically evident disease. Liver congestion and hypoxic damage of hepatocytes eventually result in predominantly centrilobular fibrosis. Doppler ultrasonography of the liver should be the initial diagnostic procedure. Hepatic venography is the reference procedure if required. Additionally liver biopsy may be helpful for differential diagnosis. The prognosis of the chronic form is acceptable compared to other chronic liver diseases.

Hepatic veno-occlusive disease (sinusoidal obstruction syndrome) after hematopoietic stem cell transplantation

Hepatic veno-occlusive disease (VOD), increasingly referred to as sinusoidal obstruction syndrome, is a well-recognized complication of hematopoietic stem cell transplantation and contributes to considerable morbidity and mortality. In the Western Hemisphere, VOD, classified as a conditioning-related toxicity, is most commonly caused by stem cell transplantation. VOD has been described after all types of stem cell transplantation, irrespective of the stem cell source, type of conditioning therapy, or underlying disease. Recognition of this disease in the posttransplantation setting remains a challenge in the absence of specific diagnostic features because many other more common conditions can mimic it. Limited therapeutic or preventive strategies are currently available for the management of VOD. In this review, we provide a comprehensive account of the pathophysiology of this disease as we understand it today, risk factors for its development, and the current state of knowledge regarding preventive and therapeutic options.

A new experimental model of specific liver hypoxia using membrane oxygenator

The present study introduces a new experimental canine model of hepatic arterial deoxygenation using a membrane oxygenator to investigate the influence of hepatic arterial hypoxia on hepatic hemodynamics and energy metabolism. Eighteen mongrel dogs weighing 10 kg each were randomly divided into three groups: group A served as a control (118.0 +/- 9.0 mmHg of hepatic arterial O2 content), group B as a moderately deoxygenated group (40 mmHg of hepatic arterial O2 content), and group C as a severely deoxygenated group (25 mmHg of hepatic arterial O2 content). Deoxygenation was achieved by perfusion of a gas mixture of O2 and N2 through the membrane oxygenator, which was interposed between the femoral artery and the proper hepatic artery, for 60 min. In group C, hypoxia decreased the mean systemic arterial blood pressure and hepatic arterial blood flow. Arterial blood ketone body ratio (AKBR = acetoacetate/3-hydroxybutyrate), which reflects the hepatic mitochondrial redox state, rapidly decreased prior to the significant increase of glutamate oxaloacetate transminase, glutamate pyruvate transminase, and lactate dehydrogenase after the initiation of hypoxia. Hepatic arterial deoxygenation to 25 mmHg for 60 min induced injury to hepatic hemodynamics, resulting in the deterioration of systemic hemodynamics even after the termination of liver hypoxia. This in vivo temporal hepatic arterial hypoxic model without alteration of inflow volume might be useful for investigating the mechanism of hypoxic injury and the critical point of liver hypoxia on hepatic and/or systemic hemodynamics and liver viability.