Clinical classification of congenital extrahepatic portosystemic shunts

Aim: Congenital extrahepatic portosystemic shunt (CEPS) is a rare anomaly in which the enteric blood bypasses the liver and drains into the systemic veins through various venous shunts. Patients with CEPS often have liver tumors and complications such as cardiac or other anomalies, but portosystemic encephalopathy and gastrointestinal bleeding occur only occasionally. The clinical problems differ for each individual with CEPS, and establishing a prognosis can be very difficult. Methods: We reviewed the clinical features of 136 reported cases of CEPS and classified these cases according to their portosystemic shunts. Results: We classified portal blood flow directly into the inferior vena cava (IVC) as type A (88 cases), portal blood flow into the renal vein as type B (36 cases), and portal blood flow into the iliac vein via an inferior mesenteric vein as type C (12 cases). Type A patients were complicated with cardiac anomalies at a higher rate than other types. Type C patients had lower prevalences of cardiac anomalies and portosystemic encephalopathy than the other types, but the prevalence of gastrointestinal bleeding was significantly higher (P < 0.0001). The prognosis of CEPS has improved, and only six deaths have been previously reported, all of which occurred in type A patients. Conclusions: We reviewed the previously reported cases of CEPS. Classification according to the portosystemic shunt system might be useful for investigating the clinical features of CEPS.     

Portal-systemic encephalopathy in non-cirrhotic patients: classification of clinical types, diagnosis and treatment

Hepatic encephalopathy is suspected in non-cirrhotic cases of encephalopathy because the symptoms are accompanied by hyperammonaemia. However, the cause of the large portal-systemic shunt formation observed in these cases is not clear, as cirrhosis and portal hypertension are absent. The frequency of such cases reported in the literature is increasing with progress and spread of abdominal imaging diagnostic techniques. Some cases have been misdiagnosed as psychiatric diseases (dementia, depression and others) and consequently patients have been hospitalized in psychiatric institutions or geriatric facilities. Some paediatric cases have also been misdiagnosed. Therefore, the importance of accurate diagnosis of this disease should be strongly emphasized. Some paediatric cases have also been misdiagnosed. When psychoneurological symptoms are suggestive of hepatic encephalopathy but objective and subjective symptoms or abnormal values of liver function tests are not sufficiently indicative of liver cirrhosis, portal-systemic encephalopathy should be suspected. Abnormal angiograms of the portal vein, superior mesenteric vein or splenic vein are conclusive evidence of portal-systemic encephalopathy. Transrectal portal scintigraphy also provides information useful for detection of shunts and a quantitative estimation of shunt index. We classified the disease into five types based on whether the shunt is formed inside or outside the liver. Type I (intrahepatic type) designates cases in which shunts are located between the portal and systemic veins. Type II designates a type of intra/extrahepatic shunt that originates from the umbilical part of the portal vein and serpentines in the liver, then leaves the liver. Type III (extrahepatic type) occurs most frequently. Type IV (extrahepatic) is accompanied by shunts similar to those in type III, but hepatic pathology presents as idiopathic portal hypertension. Type V (extrahepatic) represents the congenital absence of the portal vein, where the superior mesenteric vein joins the intrahepatic inferior vena cava or the left renal vein. The prevalence of each type in our country was examined by a nationwide investigation. In addition to the conventional diet or drug treatments, obliteration by less invasive interventional radiology using a metallic coil and ethanol has recently been used more frequently than surgical occlusion of shunts. Shunt-preserving disconnection of portal and systemic circulation and partial splenic artery embolization are also performed. International investigation of the disease status and establishment of diagnostic and therapeutic methods for the disease are awaited and investigation of long-term prognosis after therapy is also necessary.     

Surgical treatment for an extrahepatic portosystemic shunt: a case report

An extrahepatic portosystemic shunt that has neither liver cirrhosis nor portal hypertension is rare. A 60-year-old Japanese woman who had been suffering chronic liver disease and anemia with mild disorientation was admitted to investigate general fatigue with dizziness and disorientation. The laboratory data revealed mild pancytopenia and liver dysfunction including hyperammoniemia, an increased Indocyanine Green 15-min retention rate, and a decreased Fischer's ratio. Color Doppler ultrasonography, computed tomography, and arterial portography revealed an extrahepatic portosystemic shunt that extended tortuously from the superior mesenteric vein into the inferior vena cava, and decreased blood flow in the main portal vein. Judging from intraoperative measurement of portal pressure and intraoperative portography, shunt ligations were performed at both the efferent portion of shunt from the superior mesenteric vein and the afferent portion of the shunt into the inferior vena cava, and resection of the spleen was also performed. On the postoperative laboratory data, pancytopenia disappeared, and liver function improved. Postoperative abdominal imaging showed increased blood flow in the main portal vein and disappearance of the shunt vessel. Moreover, symptoms present before surgery also disappeared. In conclusion, surgical treatment of extrahepatic portosystemic shunts may result in better postoperative quality of life if it is performed in carefully selected patients.     

An unusual case of ascites

A 76-year-old woman with abdominal pain and diarrhoea developed ascites that did not respond to treatment. There were no signs of liver damage. Abdominal ultrasonography with colour Doppler revealed an arterial-like flow in the enlarged splenic vein. Using selective mesenteric arteriography, we were able to diagnose a shunt between the inferior mesenteric artery and the inferior mesenteric vein. This is an unusual case of ascites due to prehepatic portal hypertension secondary to an extrahepatic arterioportal fistula.     

An inferior mesenteric-caval shunt via the internal iliac vein with portosystemic encephalopathy

We report here a case of an unusual extrahepatic portosystemic venous shunt in a 37-year-old woman without liver cirrhosis or portal hypertension, who developed portal systemic encephalopathy. Angiography demonstrated an inferior mesenteric-caval shunt characterized by the presence of direct communication of the inferior mesenteric vein with the left internal iliac vein. After the treatment with percutaneous transcatheter embolization of the shunt via a femoral vein approach using coils, she had no episode of portal systemic encephalopathy.     

Effective balloon-occluded retrograde transvenous obliteration of the superior mesenteric vein–inferior vena cava shunt in a patient with hepatic encephalopathy after living donor liver transplantation

Balloon-occluded retrograde transvenous obliteration (BRTO) has become a common and effective procedure for treating hepatic encephalopathy due to a portosystemic shunt related to cirrhosis of the liver. However, this method of treatment has rarely been reported in patients after liver transplantation. Here, we report the case of a 52-year-old patient who underwent living donor liver transplantation (LDLT) due to hepatitis C virus-infected hepatocellular carcinoma that was complicated with portal vein thrombosis and a large portosystemic shunt between the superior mesenteric vein (SMV) and inferior vena cava (IVC). The SMV–IVC shunt was not obliterated during LDLT because there was sufficient portal flow into the graft after reperfusion. However, the patient was postoperatively complicated with encephalopathy due to the portosystemic shunt. BRTO was performed and was demonstrated to have effectively managed the encephalopathy due to the SMV–IVC shunt, while preserving the hepatic function after LDLT.     

Extrahepatic portacaval shunt via a magnetic compression technique: A cadaveric feasibility study

AIM: To explore the anatomical feasibility of portacaval shunt using a magnetic compression technique(MCT) in cadavers.METHODS: Computed tomography(CT) images of 30 portal hypertensive patients were obtained.The diameters of the portal vein(PV),the inferior vena cava(IVC),and distance between the two structures were measured.Similar measurements were performed on 20 adult corpses.The feasibility of portacaval shunt based on those measurements was analyzed.First stage of the extrahepatic portacaval shunt using MCT was performed on five cadavers.Specifically,the PV and IVC were exposed through an abdominal incision of the cadavers.The parent magnet was introduced from the femoral vein and was delivered into the IVC by an anchor wire and a 5F Cook catheter.The daughter magnet was introduced into the PV through the splenic vein using aninterventional guide wire.When the daughter magnet met the parent magnet,they automatically clipped together and the first stage of the portacaval shunt was set up.RESULTS: The average diameters of the PV and the IVC measured from the 30 CT image were 14.39 ± 2.36 mm and 18.59 ± 4.97 mm,respectively,and the maximum and minimum distances between the PV and the IVC were 9.79 ± 4.56 mm and 9.50 ± 4.79 mm,respectively.From 20 cadavers,the average diameters of the PV and the IVC were 14.48 ± 1.47 mm and 24.71 ± 2.64 mm,and the maximum and minimum distances between the PV and the IVC were 10.14 ± 1.70 mm and 8.93 ± 1.17 mm,respectively.The distances between the PV and the IVC from both the CT images and the cadavers were within the effective length of portacaval anastomosis using MCT(30.30 ± 4.19 mm).The PV and IVC are in close proximity to each other with no intervening tissues or structures in between.Simulated surgeries of the first stage using MCT on five cadavers was successfully performed.CONCLUSION: Anatomically,extrahepatic portacaval shunt employing MCT is highly feasible in humans.     

Hemodynamic consequences of portal decompression: which is the optimal shunt?

Increased sinusoidal resistance in cirrhosis results in a decrease of the portal and a compensatory increase of the arterial blood supply to the liver. With increasing vascular resistance and development of extrahepatic collaterals stagnation and even reversion of the portal blood flow may occur. In the latter condition, the arterial blood leaves the liver through two routes: 1) through the sinusoids and the hepatic veins, and 2) through the portal vein. Experimental and clinical studies revealed that the arterio-portal pathway is metabolically inferior to the regular arterio-hepatic-venous pathway. This suggests a decrease in liver function with an increased incidence of hepatic encephalopathy (HE) in patients with reversed portal blood flow. Based on these findings, surgical shunts may be classified according to their effect on the arterial liver perfusion. The end-to-side shunt and the distal splenorenal shunt (DSRS) do not cause diversion of the arterial liver perfusion. In contrast, side-to-side shunts, with the portal vein available as an outflow tract, consistently lead to diversion of the arterial blood supply resulting in reversed portal blood flow. Thus, side-to-side shunts are supposed to have an increased incidence of HE due to decreased liver function. This hypothesis is supported by 7 controlled and randomized studies which reveal comparable results of end-to-side shunts and DSRS but significant disadvantages of side-to-side shunts compared to DSRS.     

Left trisegmentectomy and combined resection of the inferior vena cava, without reconstruction, for giant cystadenocarcinoma of the liver

A 54-year-old woman with giant liver cystadenocarcinoma underwent left trisegmentectomy with combined resection of the inferior vena cava (IVC) and the right hepatic vein. As a result, only the right inferior hepatic vein was preserved as a drainage vein. Because the perivertebral plexus and the azygos vein were both well developed, neither veno-venous bypass nor IVC reconstruction was performed. The developed collateral veins acted as the venous drainage pathway to maintain a stable systemic circulation. On the seventh postoperative day, portal vein flow dramatically decreased and the patient tended to liver failure. Prostaglandin E₁ (PGE₁) was administrated via the superior mesenteric artery. The portal flow then gradually increased and liver failure was avoided. Six months after the operation, she was re-admitted due to obstructive jaundice and presented with complete stenosis of the common bile duct (CBD). The jaundice persisted and liver dysfunction progressed. The patient died seven months after the operation. The confluence of the right inferior vein and the IVC could have been deformed, causing outflow blockade. The intrinsic shunt was not good enough to act as the drainage pathway, and IVC reconstruction may have been needed.     

Abernethy malformation with multiple aneurysms: incidentally found in an adult woman with Caroli’s disease

Abernethy malformation is a rare anomaly with partial or complete congenital absence of the portal vein and subsequent development of extrahepatic portocaval shunts. We present the case of a 28-year-old woman who was incidentally diagnosed with type II Abernethy malformation and multiple aneurysms during an investigation for nonspecific abdominal pain and fever. The patient had been diagnosed with Caroli’s disease at the age of 10 and liver cirrhosis, portal hypertension a few years before. To the best of our knowledge, this is the first case reported with all such congenital anomalies associated together. Ultrasound, computed tomography, including three-dimensional reconstruction, and magnetic resonance imaging were performed which revealed a side-to-side shunt between the extrahepatic portal vein and the inferior vena cava, multiple aneurismal cystic dilation of the spleen artery and left renal artery, and extensive intrahepatic bile duct cysitic dilation with calculus formation. Etiology, clinical significance and management strategies with regard to these abnormalities are discussed.     

Disappearance of hepatic encephalopathy and improvement of liver function after surgical treatment of portal-systemic shunt in a patient with liver cirrhosis

Large portal-systemic shunts in cirrhotic patients often cause recurrent hepatic encephalopathy and might promote liver dysfunction because of the reduced portal blood flow. We report a case of liver cirrhosis in which hepatic encephalopathy disappeared and liver function improved together with an increase of hepatopetal portal blood flow and liver volume after shunt resection. A 70-year-old woman with liver cirrhosis was admitted because of recurrent disorientation. Serum ammonia levels ranged from 174 to 321 micrograms/dL. Computed tomography demonstrated an atrophic liver and a large shunt. Portography disclosed that this shunt originated from the superior mesenteric vein and flowed into the inferior vena cava, common iliac vein and ovarian vein. Portal blood flow was poor because of the deviation into this shunt. After the surgical resection of the shunt, ammonia levels were normalized and hepatic encephalopathy no longer occurred. Portography and computed tomography after surgery demonstrated that hepatopetal portal blood flow evidently improved and the liver volume increased (before 369; after 574 cm3). Two years after surgery, hepaplastin test and serum albumin level improved from 41 to 76% and from 2.7 to 3.4 g/dL, respectively. This case supports the effectiveness of shunt resection for hepatic encephalopathy and the deteriorated liver function in cirrhotic patients with large portal-systemic shunt.     

Analysis of hepatic hemodynamics by a new method of per-rectal portal scintigraphy using 99mTcO4- (direct intramural administration of radioisotope)

To depict of porto-systemic collaterals clearly, and to analyze of hemodynamics of liver, we developed new method of per-rectal portal scintigraphy (direct intramural administration of 99mTcO4- by 23G needle). And we used this method in patient with liver diseases (acute hepatitis: 5, chronic hepatitis: 7, liver cirrhosis: 25 cases). From time activity curve of the liver and the heart, liver/heart ratio; index of porto-systemic shunt via inferior mesenteric vein (IMV) and first flow ratio(k); index of portal blood flow from IMV pathway/index of hepatic total blood flow were calculated. In our method, the images of portal vein, liver, heart, especially porto-systemic collaterals were visualized more clearly than enema methods. The liver/heart ratio was significantly lower in patients with liver cirrhosis than that in non-cirrhotic patients (p less than 0.01), which indicated that patients with liver cirrhosis had more porto-systemic collaterals than non-cirrhotic diseases. The k was more lower in liver cirrhosis than in acute hepatitis (p less than 0.01). And the k was also more lower in chronic hepatitis than in acute hepatitis (p less than 0.1), which indicated that portal blood flow via IMV reduced in early stage of chronic liver diseases. In conclusion, new method of per-rectal portal scintigraphy has more advantage for analysis of hepatic hemodynamics than enema methods.     

The study of endotoxin levels in portal venous system in liver cirrhosis

In the patients with liver cirrhosis, endotoxin levels were measured in portal venous system by the toxicolor method and the mechanism of endotoxemia in the peripheral vein was studied. On endotoxin levels in portal venous system, the superior mesenteric vein had the highest level. Endotoxemia was observed most frequently in the superior mesenteric vein (78%), and 50% in the truncal portal vein and 55% in the peripheral vein. The hepatic "endotoxin extraction ratio" which is considered to reflect the Kupffer cell function of clearing endotoxin and the severity of cirrhosis were not related each other. On the other hand, in view of the extrahepatic portal shunt, systemic endotoxemia appeared more frequently in the patients with the other collaterals than the esophageal varices. Therefore, it was concluded that systemic endotoxemia in liver cirrhosis was related with the type of extrahepatic portal collaterals.     

Postsurgical chylous ascites in sarcoidosis with portal hypertension

A patient with extensive thromboses of portal and mesenteric veins and sarcoid of the liver developed recurrent pulmonary emboli, which necessitated the insertion of an umbrella into the inferior vena cava. Chylous ascites appeared shortly thereafter; the ascitic fluid fat content was strikingly reduced after reduction of dietary long chain triglycerides, but the ascitic fluid volume was reduced only after insertion of a peritoneovenous shunt (LeVeen). The shunt was found to be nonfunctioning 4 months later, but ascites did not recur. Seven years later, while eating a normal diet and still having a nonfunctioning shunt, he remains free of ascites. We postulate that iatrogenic obstruction of the inferior vena cava in the presence of mesenteric and portal vein thromboses, as well as obstruction of mesenteric lymphatics by sarcoid lymphadenopathy, led to the formation of chylous ascites and that establishment of adequate mesenteric and portal venous and/or lymphatic collateral circulation was responsible for his sustained improvement.     

Peripheral portosystemic shunt and its selectivity changes measured on duplex ultrasound

BACKGROUND/AIMS: Portosystemic shunts offer a symptomatic treatment for portal hypertension. Their main disadvantage is decreased perfusion of the liver with portal blood. Change of peripheral shunts into total shunts after a period of time is described. This study aims to evaluate long-term hemodynamic changes in peripheral portosystemic shunts. METHODOLOGY: The study was based on 12 patients in whom distal splenorenal shunts 8 patients) and mesocaval shunts (4 patients) were indicated respectively. Duplex sonography was used to measure the blood flow in the portal, splenic and mesenteric veins before shunt surgery and minimally 14 months postoperatively. RESULTS: It was found that the reduction of the portal blood flow was not critical and no centralization of the shunt was observed. CONCLUSIONS: Long-term blood flow in the portal vein was not severely reduced after peripheral portosystemic shunt creation, therefore the peripheral portosystemic shunt still has a role in the treatment of some patients with portal hypertension.     

Evaluation of Inferior Mesenteric Vein Blood Flow Circulation with Per-Rectal Administration of Thalliuni-201 and Technetium-99m Pertechnetate

We administered both per-rectal thallinm-201 (²⁰¹TI) and technetium-99m pertechnetate (^99mTc) to patients with liver diseases in order to understand the abnormalities of inferior mesenteric vein (IMV) blood flow circulation. As ²⁰¹TI heart-to-liver uptake ratio (H:L), reflecting the degree of portal-systemic shuntings (PSS), increased, the visualization of IMV in general became poor on ^99m Tc scintigrams. ²⁰¹TI H:L in the group with no visualization of IMV on ^99m Tc scintigrams was significantly higher than in the group with clear visualization of IMV ( p < 0.001). However, there were patients who showed IMV visualization among those with high ²⁰¹ TI H:L. In these patients, it was considered that IMV blood flowed in the normograde direction, escaping mainly through PSS at the upper part of the portal system, and resulting in elevated H:L. In the patients without IMV visualization, IMV blood flowed in the retrograde direction, escaping mainly through collaterals at the lower part of IMV. Inferior vena cava (IVC) was visualized on ^99m Tc scintigrams in some patients without IMV visualization, indicating the presence of collaterals from the distal part of IMV to IVC. Per-rectal studies using these two radiotracers can afford us useful informations on the abnormalities of IMV blood flow hemodynamics in patients with liver diseases.     

Assessment of portal blood flow by isotope splenoportography. Methodology and 1st results in cirrhosis

The authors report a new non-invasive method of portal blood flow (PBF) measurement, after injection of a radiotracer into the spleen. PBF was equal to the product of the radiotracer bolus velocity and the cross-section area of the portal vein as measured by ultrasonography. In 16 patients with cirrhosis, the velocity of the portal blood flow (V) and PBF were determined in 11 cases. In the remaining 5 patients, failures were explained by either a total extrahepatic shunt (3 cases) or difficulties of scanning view analysis (2 cases). Mean values of V and PBF were 8.8 +/- 2.5 cm/s and 579 +/- 193 ml/min respectively, which represent a reduction of 50 p. 100 compared to estimated normal values. This method was also useful to appreciate the fraction of PBF which is supposed to reach the liver cells called the "actual portal blood flow" (APBF). APBF was equal to PBF minus the fraction of blood flowing through intrahepatic shunts and/or the recanalized umbilical vein. In the 16 cases, mean values were 528 +/- 184 ml/min for APBF, 11.9 +/- 1.7 cm for the portal vein diameter, and 53 +/- 34 p. 100 for spleen blood flow fraction going through porto-systemic collateral veins. Significant intrahepatic shunt was observed in one patient only out of 13 without total extrahepatic shunt, i. e., in 8 p. 100 of the cases. The impossibility of measuring PBF when a total extrahepatic shunt is present is a drawback in the use of this new technique.(ABSTRACT TRUNCATED AT 250 WORDS)     

Liver transplantation in the setting of a spontaneous shunt between superior mesenteric vein and right renal vein

Shunts between the superior mesenteric vein (SMV) and the right renal vein (RRV) are very rare. Here, we describe and depict the rare case of a liver transplant (LT) in the setting of shunt between SMV and RRV. A 67-year-old white man presenting with Child C cirrhosis secondary to hemochromatosis and persistent encephalopathy was listed for LT. Preoperative abdominal angiotomography revealed the presence of a large spontaneous shunt between the SMV and the RRV. The patient underwent LT by receiving a liver from a 17-year-old brain-dead deceased donor victim of trauma. A large shunt between the SMV and the RRV was confirmed intraoperatively. Although there was no portal vein (PV) thrombosis, the PV was atrophic and had a reduced flow. PV pressure was 22 mmHg (an arterial line was inserted inside the PV stump, and this line was connected to a common pressure transducer, the pressure readings was expressed in the anesthesia monitor). After shunt ligation PV pressure increased to 32 mmHg. There were no post-transplant vascular complications, and the patient was discharged home in good health. Preoperative study of all LT candidates with angio CT scan is mandatory. Whenever there is PV thrombosis, an attempt to remove the entire thrombus is warranted. After thrombectomy or whenever there is not PV thrombosis, all large shunts should be ligated. PV pressure and flow should be measured before and after shunt ligation. In the absence of PV thrombosis, ligation of the shunt should enable an increase in PV flow and pressure, as reported herein.     

Clinical and Portal Hemodynamic Features in Cirrhotic Patients Having a Large Spontaneous Splenorenal and/or Gastrorenal Shunt

Clinical and portal hemodynamic features in 28 cirrhotic subjects with a large spontaneous spleno- and/or gastrorenal shunt were studied in comparison with 30 control cirrhotic cases without such collaterals. Forty-six percent of the former had chronic hepatic encephalopathy, but none of the latter was encephalopathic. These patients with large renal shunts were divided into those with and those without encephalopathy. Large esophageal varices were significantly less common in patients with a large shunt and encephalopathy compared with those who had a large shunt but no encephalopathy, and the control. But there was no significant difference of past variceal bleeding among these three groups. In all those with encephalopathy, part of superior mesenteric venous blood was shunting through these collaterals into the left renal vein or inferior vena cava, but the same was not demonstrable in patients with a large shunt and no encephalopathy and control cirrhotics. In the chronic encephalopathic, portal venous flow was estimated to be less than one-half of that in control cirrhotics, and the portion of superior mesenteric venous blood that was flowing hepatofugally through a large shunt into the left renal vein seemed about the same or greater than the portal venous flow. Thus, a large spontaneous spleno- and/or gastrorenal shunt might prevent development of large esophageal varices but not variceal hemorrhage and it increased a risk of chronic hepatic encephalopathy.