The incidence of portal vein thrombosis at liver transplantation.

The incidence of portal vein thrombosis was examined in 885 patients who received orthotopic liver transplantations for various end-stage liver diseases between 1989 and 1990. The thrombosis was classified into four grades. Grade 1 was thrombosis of intrahepatic portal vein branches, grade 2 was thrombosis of the right or left portal branch or at the bifurcation, grade 3 was partial obstruction of the portal vein trunk, and grade 4 was complete obstruction of the portal vein trunk. Among the 849 patients without previous portosystemic shunt, 14 patients (1.6%) had grade 1, 27 patients (3.2%) had grade 2, 27 patients (3.2%) had grade 3 and 49 patients (5.8%) had grade 4 portal vein thrombosis. The incidence of portal vein thrombosis was highest (34.8%) in the patients with hepatic malignancy in the cirrhotic liver, followed by those with Budd-Chiari syndrome (22.2%) and postnecrotic cirrhosis of various causes (15.7%). The patients with encephalopathy, ascites, variceal bleeding, previous splenectomy and small liver had significantly higher incidences of portal vein thrombosis than the others. The total incidence of portal vein thrombosis among the 36 patients with previous portosystemic shunt was 38.9%, which was significantly higher than that (13.8%) of those without shunt.     

Altered Liver Morphology After Portal Vein Thrombosis: Not Always Cirrhosis

The macroscopic appearance of the liver after primary portal vein thrombosis often mimics cirrhosis, despite the absence of bridging fibrosis at histology. The purpose of this study was to describe unique morphologic changes of the liver after portal venous thrombosis. A retrospective review was performed to find patients with portal vein thrombosis and a corresponding noncirrhotic liver biopsy. The CT appearance of the liver was then evaluated, and the liver was categorized as having either peripheral or central hepatic atrophy. Of 15 patients included in this study, 12 had peripheral atrophy of the liver, while the remaining three had central atrophy. We concluded that maintenance of central portal venous blood flow and resultant relative peripheral atrophy of the liver may account for a distinctive rounded configuration of the liver after acute portal vein thrombosis. Awareness of this appearance after primary portal vein thrombosis may prevent an erroneous diagnosis of cirrhosis.     

Duplex Doppler ultrasound of the ligamentum teres and portal vein: A clinically useful adjunct in the evaluation of patients with known or suspected chronic liver disease or portal hypertension

The prevalence and potential value of the detection of signs of portal hypertension by duplex Doppler ultrasound (DDU) of the ligamentum teres and portal vein in patients with known or suspected chronic liver disease and/or portal hypertension was studied in 136 consecutive patients undergoing clinical assessment including that of liver histopathology. Portal hypertension was considered to be present when any of the following DDU signs, previously demonstrated to be specific for portal hypertension, were present: an enlarged and/or patent para-umbilical vein, portal vein obstruction or hepatofugal flow in the portal vein. Of 123 patients with parenchymal liver disease, eighty-three had cirrhosis and, of these, portal hypertension was detected on DDU criteria in 86% of alcoholic cirrhotics and 67% of non-alcoholic cirrhotics. Of the 42 patients with non-cirrhotic liver disease, 1 of 7 patients with metastatic liver disease and 3 of 5 patients with alcoholic hepatitis had DDU signs of portal hypertension. Thus, in patients with parenchymal liver disease, DDU had a sensitivity of 73%, specificity of 90% and predictive values of 94 and 62% for positive and negative studies respectively for the detection of cirrhosis. In all 14 patients with portal hypertension secondary to vascular occlusive diseases, DDU examination of the ligamentum teres, portal vein and hepatic vein gave an accurate guide to the site of the occluding lesion. The high positive predictive value of DDU and its ability to aid in localizing the site of increased resistance to flow through the liver suggest that DDU of the ligamentum teres and portal vein is a potentially useful non-invasive adjunct in the assessment of patients with suspected or known liver disease or portal hypertension.     

Clinical Characteristics of Portal Hemodynamics in Alcoholic Liver Cirrhosis

Background: Low incidence of reversal blood flow at the portal vein has been reported by measurement in larger and extrahepatic blood vessels but not in intrahepatic blood vessels in patients with liver cirrhosis. Moreover, there is little information regarding the incidence of reversal blood on the basis of the cause of liver cirrhosis. The aim of this study was to measure the reversal blood flow in the portal vein including intrahepatic branches in patients with alcoholic and viral cirrhosis.
Methods: The blood flow in the portal vein and existence of portosystemic shunt were studied in 52 and 27 patients with alcoholic and viral cirrhosis, respectively, by Doppler ultrasonography. The parameters of liver function test and the prevalence of ascites and esophageal varices were compared between patients with and without reversal blood flow.
Results: Reversal blood flow at the portal vein was found only in patients with only alcoholic cirrhosis (17 of 52 patients) but not in any patients with viral cirrhosis (0 of 27 patients; p < 0.05). The incidence of portosystemic ascites and red color of esophageal varices was also higher in patients with alcoholic cirrhosis with reversal blood flow in the portal vein compared with patients without reversal blood flow ( p < 0.05).
Conclusions: Reversal blood flow in the portal vein is a characteristic feature of alcoholic cirrhosis. The presence of reversal blood flow indicates severe liver diseases, and this feature may have prognostic importance for patients with alcoholic cirrhosis.     

肝硬化门静脉血栓形成的危险因素

门静脉血栓(PVT)在肝硬化患者中较常见,合并PVT的静脉曲张更容易出血,止血失败率及再出血率更高,对于肝移植患者,其预后更差。目前PVT形成的相关危险因素较多,如肝功能严重程度、非选择性β受体阻滞剂的使用、门静脉血流速度等。重点对肝硬化PVT形成的危险因素进行综述,以进一步了解PVT形成的相关机制和PVT的危险程度。     

Portal vein arterialization technique for liver transplantation patients

Liver transplantations were performed on two patients with hepatic failure caused by liver cirrhosis. Hard obsolete thrombi and portal venous sclerosis were observed in the major portal veins of both patients. The arteria colica media of one recipient and the portal vein of the donor were anastomosed end-to-end. The hepatic artery of the first donor was anastomosed end-to end with the gastroduodenal artery of the first recipient; meanwhile, the portal vein of the second donor was simultaneously anastomosed end- to-end with the common hepatic artery of the second recipient. The blood flow of the portal vein, the perfusion of the donor liver and liver function were satisfactory after surgery. Portal vein arterialization might be an effective treatment for patients whose portal vein reconstruction was difficult.     

肝硬化患者肝功能失代偿状况与门脉管径的关系

目的:探讨肝硬化患者肝功能失代偿状况、食管静脉曲张程度与门脉主干内径及脾静脉内径的关系。方法:对100例肝硬化失代偿期患者进行肝功能Child-pugh分级,内镜检查判断食管静脉曲张程度,彩色多谱勒B超检测门静脉主干内径及脾静脉内径。结果:肝功能分级越差,门静脉与脾静脉的内径越大(P<0.05),且随着门静脉及脾静脉内径增大,食管静脉曲张程度亦加重(P<0.05)。结论:门静脉及脾静脉内径能间接体现门静脉高压的程度,继而反映肝功能失代偿状况。     

Role of portal and splenic vein shunts and impaired hepatic extraction in the elevated serum bile acids in liver cirrhosis

To study the mechanism for the elevation of serum bile acids in liver cirrhosis, bile acid concentrations were measured in the portal, superior mesenteric, and splenic veins, using percutaneous transhepatic catheterization, and compared with those of peripheral veins in 41 patients with mild to moderately advanced cirrhosis. The demonstrated gradient of bile acid concentration was superior mesenteric vein greater than portal vein greater than peripheral vein nearly equal to splenic vein, suggesting that the superior mesenteric vein is the main route of transport for the intestinally absorbed bile acids. Bile acid concentrations in peripheral vein were correlated with the measured portal and splenic vein shunt indexes. The ursodeoxycholic acid oral tolerance test carried out in 10 patients during portal vein catheterization demonstrated that hepatic extraction of this bile acid was correlated with indocyanine green clearance and that it was inversely correlated with portal vein shunt index. These findings are consistent with the view that distorted hepatic blood flow has a significant role in elevating serum bile acid, at least in patients with moderately advanced liver cirrhosis.     

彩色多普勒超声引导下经皮门静脉穿刺留置导管的临床应用

目的探讨彩色多昔勒超声引导下经皮经肝穿刺门静脉留置导管的临床应用价值。方法100例肝细胞癌或转移癌患者，在彩色多普勒超声引导下经皮经肝穿刺门静脉置人中心静脉导管，观察穿刺及置管成功率、导管留置天数、并发症发生率和治疗效果。结果在100例患者中，穿刺一次成功率和置管一次成功率为98．0％；早期导管留置天数为7-14d，平均9．2±2．7d，改进后为23-60d，平均44．7±13．5d；无严重并发症发生。经门静脉注药治疗原发性肝癌和转移性肝癌的疗效优于外周静脉给药。讨论该方法可重复门静脉给药，能增加局部药物浓度，提高药物治疗的效果．并且安全、可靠，无严重并发症。     

Use of an interpositional venous graft posterior to the pancreas for LDLT patients with portal vein thrombosis

Portal vein thrombosis is a risk factor in patients who require liver transplantation, because it is often difficult to treat portal vein thrombosis, especially when it involves the confluence of the superior mesenteric vein and splenic vein. Since some transplant centers that perform living-donor liver transplantation do not have cryopreserved cadaveric vein grafts available and do not use graft veins that are long enough for a jump graft, it is difficult to reconstruct the portal vein with interpositional vein grafts in patients with portal vein thrombosis. We describe the treatment of portal vein thrombosis with an interpositional vascular graft posterior to the pancreas in a living-donor liver transplantation patient without using a jump graft. This method provided a shorter rout between the donor and recipient portal vein than a jump graft. Our experience suggests that this solution can be helpful in treating portal vein thrombosis.     

Value of sonographic representation of the portal artery in clinical practice

While in chronic liver diseases we up to now above all depended on laparoscopic indices of the hypertension of the portal vein, also the non-invasive sonography is able to prove an adequate morphological substrate in form of the dilated splenic vein and the portal vein. A comparative study of 50 patients with liver cirrhosis who underwent laparoscopy shows significantly higher values in patients with clear portal hypertension. Provided a correct valuation of the findings by the clinical and a subtle examination technique, the non-invasive sonographic estimation of the portal vein represents a prognostically important diagnostic contribution in patients with chronic liver diseases.     

Portal venous stent placement for treatment of portal hypertension caused by benign main portal vein stenosis

AIM: To evaluate the value of endovascular stent in the treatment of portal hypertension caused by benign main portal vein stenosis. METHODS: Portal vein stents were implanted in six patients with benign main portal vein stenosis (inflammatory stenosis in three cases, postprocedure of liver transplantation in another three cases).Changes in portal vein pressure,portal vein patency, relative clinical symptoms, complications,and survival were evaluated. RESULTS: Six metallic stents were successfully placed across the portal vein stenotic or obstructive lesions in six patients. Mean portal venous pressure decreased significantly after stent implantation from (37.3±4.7) cm H2O to (18.0±1.9) cm H2O.The portal blood flow restored and the symptoms caused by portal hypertension were eliminated. There were no severe procedure-related complications. The patients were followed up for 1-48 mo. The portal vein remained patent during follow-up. All patients survived except for one patient who died of other complications of liver transplantation. CONCLUSION: Percutaneous portal vein stent placement for the treatment of portal hypertension caused by benign main portal vein stenosis is safe and effective.     

The significance of portal vein embolization in the treatment of colorectal liver metastases

The first aim of the present paper was to evaluate hypertrophy of liver parenchyma after portal vein embolization in patients after systemic chemotherapy for colorectal carcinoma metastases and planned extensive liver resections. The second aim was to study whether hypertrophy of the liver parenchyma remnant after could influence the postoperative course large liver resections in long-term chemotherapy within complex therapy of colorectal carcinoma.The prospective study comprised of 43 patients with colorectal hepatic metastases in whom liver resections of 4-5 segments were planned (Table 1). All patients underwent complex therapy of colorectal carcinoma, including chemotherapy consisting of 6-12 therapeutic cycles. Time interval between chemotherapy and liver resection was 2-24 months (mean interval of 8 months). Twenty patients whose presumed liver parenchyma remnant was less than 40% of total liver volume were indicated for portal vein embolization (mean liver parenchyma remnant of 29%). This was always embolization of the right portal branch. Twenty-three patients were primarily indicated to liver resection. RESULTS: Hypertrophy of the left liver lobe occurred in all 20 patients. After portal vein embolization, the volume of left liver increased on average from 476 ml (282-754) to 584 ml (380-892) (P < 0.05). Mean hypertrophy of left liver lobe after portal vein embolization was 28.5%. The measured parenchyma remnant after tumor resection increased from 29% up to 38% by hypertrophy. Mean values of ALT and AST in the postoperative period were significantly different in the groups in this study. The values of alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GMT) were lower in patients after portal vein embolization (P < 0.05). Significant differences were in postoperative level of serum bilirubin, bilirubin levels in patients after portal vein embolization were 2-3 times lower than in the group of patients after immediate surgery (P < 0.05). he values of prothrombin time were also significantly lower in patients who underwent surgery without previous portal vein embolization (P < 0.05).     

Effect of meal on portal hemodynamics in healthy humans and in patients with chronic liver disease

The effect of a standard Italian meal on portal hemodynamics was evaluated in 12 normal subjects, in 11 patients with chronic active hepatitis and in 11 patients with liver cirrhosis using duplex Doppler ultrasound, which allows a noninvasive assessment of portal blood flow. In the fasting state, the portal vein caliber was significantly higher in patients with liver cirrhosis than in normal subjects and patients with chronic active hepatitis, whereas the mean flow velocity in the portal vein was significantly lower in this group. Basal flow volume of the portal vein was greater in patients with liver cirrhosis than in normal subjects and patients with chronic active hepatitis. Sixty minutes after the standard meal, we observed both in normal subjects and in patients with chronic active hepatitis a significant increase of mean caliber, mean velocity and flow volume in the portal vein, whereas in patients with liver cirrhosis, these parameters remained almost unchanged. In addition, the examination of individual patterns showed that flow velocity and flow volume in the portal vein decreased in some cirrhotic patients after the meal. This behavior is probably related to the hypertensive state in the splanchnic venous bed and diversion of splanchnic blood flow into spontaneous portosystemic collaterals.     

Liver transplantation with cavoportal or renoportal anastomosis: a solution in cases of diffuse portal thrombosis

OBJECTIVE: Liver transplantation was contraindicated in patients with diffuse thrombosis of the portal vein until the recent use of graft portal vein reperfusion with the caval flow or one of its tributaries. Long term results of these procedures are reported here.PATIENTS AND METHODS: Eight patients with diffuse portal vein thrombosis were transplanted by portal reperfusion via latero-terminal anastomosis between the native caval vein and the graft portal vein (2 patients) or termino-terminal between the native left renal vein and the graft portal vein (6 patients).RESULTS: Three patients died 3, 3 and 6 months following transplantation from intracerebral hemorrhage, cardiac arrest, and chronic rejection respectively. Three patients had complicated portal hypertension. Five patients were alive at home with a median follow-up of 9 months (2 to 37 months) with normal liver and kinase functions.CONCLUSION: Portal reperfusion with the caval vein flow allows transplantation of patients with diffuse poral vein thrombosis. According to our experience and to the analysis of the literature, reno-portal anastomosis is preferable to cavo-portal reconstruction.     

Preoperative transhepatic portal vein embolization for impaired residual hepatic function in patients with obstructive jaundice

Fifty patients with obstructive jaundice with biliary tract carcinoma who underwent percutaneous transhepatic portal vein embolization (PTPE) were studied to evaluate the clinical utility of PTPE in preparation for extensive liver resection. PTPE was performed 2–3 weeks before surgery, via the standard contralateral approach in the first seven patients and via the ipsilateral approach, devised by the authors, in the last 43 patients. The following portal branches in which embolization was planned were all successfully embolized: the right portal vein in 35 patients; the right portal vein plus the left medial portal branch in 6; the left portal vein and the right anterior portal branch in 3; the left portal vein in 2; the right anterior portal branch in 3; and the right posterior portal branch in 1. There were no procedure-related complications. Helical computed tomography demonstrated compensatory hypertrophy of the non-embolized segments. After PTPE, 35 of the 50 subjects underwent major hepatectomy with or without portal vein resection and/or pancreatoduodenectomy; the remaining 15 were found to have peritoneal dissemination or liver metastasis, and no resection was performed. Of the 35 hepatectomized patients, 3 died of posthepatectomy liver failure, and 1 patient died of pneumonia with pulmonary lymphangitis carcinomatosis; the other 31 patients were discharged in good condition. The hospital death rate was 11.8% (4/35), and mortality directly related to the surgery was 8.6% (3/35). PTPE appears to have the potential to increase the safety of extensive liver resection for patients with obstructive jaundice.     

Treatment of portal vein tumor thrombus using ¹²5Iodine seed implantation brachytherapy

We reported two cases of liver metastasis with portal vein tumor thrombus that developed after liver transplantation for hepatocellular carcinoma (HCC). Both the patients were women aged 43 and 55 years, who had liver metastasis and portal vein tumor thrombus formation after liver transplantations for HCC. For the treatment of portal vein tumor thrombus, (125)I seeds were implanted into the hepatic tissue under the guidance of preoperative computed tomography (CT) images with a total radiation dose of 130 Gy. Enhanced spiral CT scan was performed for evaluation of the liver at 12 and 16 wk after treatment. Thereafter, upper abdominal CT examination was performed every 2-3 mo. No severe complications associated with the (125)I seeds were seen in these two patients. The upper abdominal CT images (obtained after 3 and 4 mo of treatment) showed that the thrombosis reactions were complete reaction and restoration of the patency of the partially obstructed portal vein with partial obstruction. In the case with complete obstruction of the portal vein, the thrombosis was resolved completely, but blood flow could not be restored. After this treatment, one of the patients is still alive, while the other died within 6 mo after the treatment due to lung metastasis complicated with lung infection, leading to respiratory failure.     

Influence of the degree of liver failure on portal blood flow in patients with liver cirrhosis

Portal vein haemodynamics as demonstrated by the pulsed Doppler system were studied in 37 patients with cirrhosis who had been classified in three groups (A, B, and C) in accordance with the degree of liver failure. Maximal inner diameter of the portal vein was significantly lower in patients who were considered to be in good condition (group A) than in patients with moderate and severe liver failure (group B and group C) (p less than 0.001). A significant difference was also found between group A and group B and between group A and group C with regard to the portal blood velocity and portal blood flow (p less than 0.001). In accordance with the presence and size of the oesophageal varices, in patients with large varices the portal blood velocity and portal blood flow were significantly lower than in patients without varices (p less than 0.001), whereas maximal inner portal vein diameter was significantly higher (p less than 0.001). This study demonstrated that in patients with cirrhosis circulatory alterations in the portal vascular bed may be, at least in part, an indicator of the stage of liver disease.     

Hemodynamics of intrahepatic portal vein studied in healthy subjects and liver cirrhosis by pulsed Doppler method]

The hemodynamics of the intrahepatic portal vein in 35 healthy subjects and 74 patients with liver cirrhosis was studied by measuring blood flow velocity with pulsed Doppler ultrasound technique. The flow velocity of portal vein decreased from the portal trunk to the first branches and to the second branches in the right and left lobes. Especially, an abrupt decrease of the flow velocity in the umbilical part of the left portal vein was characteristic of hemodynamics in the intrahepatic portal vein. The flow velocity in the third branches decreased more than that of the second branch in the right portal vein, but did not exist in the left. And the velocity was almost equal in all the subsegments. Blood clots of the left portal vein in 25 of 36 lesions were found in 31 patients with intrahepatic portal vein thrombus. This characteristic hemodynamics of the left portal vein was thought to be the main cause for the formation of blood clots. In the group with liver cirrhosis, the flow velocity was lower than in healthy subjects in the portal trunk, bilateral first branches and right second branches, but did not exist in the left second branch and bilateral third branches. No interrelationship between the intrahepatic portal flow velocity and the severity of liver cirrhosis and portal hypertension was observed.     

Non-invasive diagnosis of portal vein occlusion by radionuclide angiography.

The accuracy of non-invasive radionuclide angiography in detecting portal vein occlusion was assessed in 61 patients--10 with portal vein occlusion confirmed by conventional portography, 25 with chronic liver disease and a patent portal vein (mild = 12, severe = 13), and 26 with normal liver function, who served as controls. The median percentage portal venous flow for the portal vein occlusion group was 8% (range 1-30) (consistent with negligible flow) compared with 78% (52-87) for control subjects (p < 0.005) and 68% (61-80) and 49% (23-59) respectively for patients with mild and severe liver disease (p < 0.001 and p < 0.005). At a portal venous inflow of < 20%, the procedure had a specificity of 100% and sensitivity of 90% in diagnosing portal vein occlusion. Non-invasive radionuclide angiography provides a safe and accurate screening method for evaluating portal vein patency or occlusion in the investigation of portal hypertension or before liver transplantation.