Budd-Ghiari syndrome

Introduction

Introduction to Bad Gyari Syndrome Budd-Chiarisyndrome (BCS) is a hepatic vein and adjacent inferior vena cava stenosis due to various reasons, hepatic vein and inferior vena cava blood return disorder, resulting in hepatomegaly and pain, Ascites, liver dysfunction and other clinical manifestations. basic knowledge The proportion of sickness: 0.002%-0.003% Susceptible people: no specific population Mode of infection: non-infectious Complications: shock, jaundice, splenomegaly

Cause

The cause of Bad Gayley syndrome

Causes

In the discussion of the etiology, the main causes of the disease are concentrated in thrombosis, membranous stenosis and local compression.

Thrombosis (30%):

BCS often occurs in a variety of patients with increased blood coagulation, the most reported are polycythemia vera and other myeloproliferative diseases, Wanless et al reported a group of 145 autopsy data, see polycythemia vera and unexplained myeloproliferative One-third of the disease is associated with dominant portal hypertension, and paroxysmal nocturnal hemoglobinuria (PNH) is also one of the common causes of BCS. The frequency of PCS associated with BCS is 12% to 27.3%. BCS is a long-term oral contraceptive. High incidence, adjacent organ inflammatory lesions such as ulcerative colitis and Crohn's disease are often associated with BCS, in short, elevated blood coagulation due to various reasons, can lead to the hepatic vein and / or the lower segment of the liver Vena cava thrombosis, as to why thrombosis occurred in this part, so far there is no satisfactory explanation.

Membrane formation (20%):

In 1912, Thompson and Turnbull reported the first case of inferior vena cava membranous obstruction (MOVC) in foreign literature. In 1950, Bennett reported again. Since then, MOVC has been widely reported in many countries in BCS. The occurrence of MOVC is caused by congenital lesions or acquired factors. At present, there is still controversy. Most scholars believe that MOVC is a congenital lesion caused by developmental defects. For example, Hirooka studies the inferior vena cava and liver based on pathological anatomy. The embryonic development of the segment is proposed to constitute the upper and lower segments of the inferior vena cava including part of the heart, the common hepatic vein, the hepatic sinus, and the right lower main vein. If abnormal fusion or occlusion occurs during development, several types of pathological changes may be explained. Okuda questioned the innate developmental theory of MOVC; Terabagashi et al reported a case of lupus anticoagulant-positive patients, and found that the inferior vena cava thrombosis changed the membranous obstruction by dynamic observation, thus finding evidence for the acquired formation theory of MOVC. In-depth studies have shown that erythropoietin increases, erythroid colony formation and lupus anticoagulant factors may be in blood Increased fluid coagulation - hepatic venous thrombosis - hepatic inferior vena cava membranous obstruction - Budd-Chiari syndrome plays an important role, it has also been suggested that protein C deficiency is also associated with BCS.

Partial compression (10%):

Adjacent organ lesions, including inflammation, trauma, hepatic space-occupying lesions or metastatic cancer, oppression or invasion of the inferior vena cava and hepatic veins of the liver, or the spread of liver cancer along the hepatic vein causes tumor thrombosis and thrombosis, causing obstruction.

Pathogenesis

1. Classification for the hepatic vein and / or hepatic inferior vena cava obstruction type, location and morphology of many people have made a more detailed observation, according to the nature, location, extent and extent of the obstruction, for correct treatment It is very important to choose the surgical method. Many scholars have put forward various classification opinions. The Hirooka classification is the most detailed, and the pathological characteristics, location and relationship of the inferior vena cava and hepatic vein are clarified, and the membranous obstruction is also found. There are differences between film and thick film.

Type I a: The diaphragm is above the unobstructed opening.

b: The septum is between the occluded left hepatic vein and the unobstructed right hepatic vein.

c: The diaphragm is below the open hepatic vein opening.

Type II a: The septum is above the occluded hepatic vein.

b: The diaphragm is below the occluded hepatic vein.

Type III: stenosis of the vena cava and patency of the hepatic vein.

Type IV: thrombotic occlusion of the vena cava section, hepatic vein involvement.

Type V: stenosis of the vena cava, hepatic vein involvement.

Type VI: segmental occlusion of the vena cava liver segment, involvement of the hepatic vein.

Type VII: hepatic vein occlusion.

Because Hirooka classification is too complicated, it is inconvenient to use. Wang Zhongyu comprehensively classifies various diseases according to the characteristics of inferior vena cava obstruction and hepatic vein involvement. The disease is divided into three types from the perspective of easy surgical selection.

Type I: Local stenosis or obstruction (about 57%) of the inferior vena cava diaphragm. This type is a high-level inferior vena cava diaphragm-like obstruction or fibrous obstruction. The hepatic vein is not involved, but the hepatic vein opening is located. The distal side of the inferior vena cava obstruction, therefore, in addition to obstruction of the inferior vena cava, hepatic venous return is also blocked, this type is quite common in Japan, the distal side of the inferior vena cava obstruction, blood stasis, secondary thrombosis, If the thrombus is extended, the hepatic vein opening and trunk can be blocked.

Type II: diffuse stenosis or obstruction (about 38%), diffuse stenosis or obstruction of the inferior vena cava, segmental or diffuse obstruction of the inferior vena cava, combined with left hepatic vein or right hepatic vein occlusion, or even The trunk of the hepatic vein is completely occluded, and most of the people seen in Asia and the Far East are of this type.

Type III: hepatic vein obstruction (about 5%), hepatic vein trunk or opening obstruction, inferior vena cava patency, this type occurs mostly in Western Europe and North America, often manifested as hepatic vein thrombosis or thrombophlebitis, The scholars observed that as the disease progressed, the inferior vena cava near the outlet of the hepatic vein was followed by thrombosis.

2. Pathology and pathophysiology

(1) Liver histology: BCS liver histological changes are affected by a variety of factors, first of all the degree of obstruction, such as complete obstruction, intrahepatic histological changes are more uniform; incomplete obstruction, histological changes The difference is large. The second is the cause of obstruction. For example, the blood coagulation is increased. The hepatic veins at different levels are visible to different extents. The thrombosis is different between old and new, and the blood vessel wall can also have thickening and endothelial damage. In the case of membranous obstruction, Thrombosis is rare, the blood vessel wall can be thickened to varying degrees, and finally the course of obstruction, acute occlusion, central venous and hepatic sinus congestion, dilatation, hemorrhage, hepatocyte atrophy, destruction or disappearance in the central area of the lobule; Hepatocytes can undergo fat-like changes; around the portal vein, hepatocytes are regenerated. In the case of subacute obstruction, the central wall of the lobule is thickened, fibrotic, hepatic atrophy and interlobular fibrous tissue hyperplasia; peripheral hepatocytes When regeneration is more pronounced, pseudo-nodules are formed. When chronic obstruction occurs, extensive fibrotic lesions are produced, and normal hepatic lobular structures are destroyed by fibrous tissue and regenerative nodules. Alternatively, leading to cirrhosis and portal hypertension, hepatic venous obstruction, enlarged liver congestion, increased hepatic venous pressure and sinusoidal, then increased formation of hepatic lymph, the liver capsule by overflow into the abdominal cavity and ascites.

(2) collateral circulation: The anatomical changes of the collateral circulation during BCS depend on the location and nature of the occlusion.

1 Because the three hepatic vein trunks are not all affected by occlusion, the intrahepatic veins form collateral circulation and communicate with each other.

2 The thick and abundant traffic vessels between the hepatic venous vein and the inferior vein form a hepatic-venous collateral circulation.

3 Hepatic blood flow can also be drained to the superior vena cava through the collateral circulation of the liver-sham vein.

4 portal-venous anastomosis, especially the gastric coronary veins, the short veins of the stomach and the azygous veins, the branches of the semi-singular veins agree, forming the submucosal varices in the fundus and lower esophagus.

5 hepatic dorsal vein compensatory dilatation, congestive hyperemia and hypertrophy of the tail and pressure and inferior vena cava, if the portal vein is also embolized, liver blood flow is stagnant and infarction, the patient died of liver failure in a short period of time, the incidence of BCS with portal vein thrombosis It is 20%.

Inferior vena cava obstruction, in addition to obstruction of the hepatic vein outflow tract, there are still inferior vena cava reflow obstruction, obstruction of distal vena cava dilatation, blood stasis, significant expansion in the retroperitoneum, lumbar vein, renal vein, adrenal vein and lumbar ascending vein The mutual traffic forms a collateral circulation. The blood flows through the semi-singular vein and the azygous vein to the superior vena cava. The superficial veins on both sides of the chest and abdominal wall are distorted and dilated, the blood flow is from the bottom to the top, the lower limbs and the perineum are swollen, and the superficial varicose veins are The skin of the ankle is pigmented and even ulcerative.

Prevention

Bad Gyari syndrome prevention

Targeted prevention and attention to living habits according to the cause. Health products inquiry Breakline Bad-Giari syndrome Chinese medicine treatment method No relevant information Chinese herbal medicine inquiry Breakline Bad-Giari syndrome Western medicine treatment.

Complication

Bad Gayley syndrome complications Complications, shock, jaundice, spleen

1. Acute phase: There are varying degrees of liver damage, and severe patients present with rapid death from shock or liver failure.

2. Subacute type: About one third of patients have jaundice and splenomegaly.

3. Chronic period: very long period of time, splenomegaly and esophageal varices, even hematemesis and melena, severe cases of lower extremity varicose veins, and even nutritional ulcers in the foot and ankle, bilateral lower extremity venous pressure increased.

Symptom

Budd-Gily syndrome symptoms Common symptoms Upper abdominal discomfort Abdominal limb edema Muscle tenderness Liver enlargement Abdominal pain Proteinuria

BCS occurs most often in young adults aged 20 to 45 years. In terms of gender, it is generally reported that males have a high incidence. Ascites and hepatomegaly are the most common clinical signs. The clinical manifestations are related to the obstruction site. The hepatic vein obstruction is mainly characterized by abdominal pain. , liver enlargement, tenderness and ascites; inferior vena cava obstruction on the basis of clinical manifestations of hepatic vein occlusion, often accompanied by lower extremity edema, lower extremity ulcer, pigmentation, and even lower extremity varicose veins, lesions affecting the renal vein, protein may appear Urine, even manifested as nephrotic syndrome, is clinically classified according to the patient's symptoms.

1. Acute phase: The course of the disease is more than 1 month. The clinical manifestations of this type of patients are very similar to acute hepatitis and acute severe hepatitis. Sudden abdominal pain, abdominal distension, and subsequent liver enlargement and massive ascites, abdominal wall vein expansion, with varying degrees of Liver function damage, severe cases of severe death in shock or liver failure.

2. Subacute type: the course of disease is within 1 year, the clinical manifestation is the most typical, ascites is the basic feature. In more than 90% of patients, ascites grows rapidly, persists, mostly intractable ascites, most patients have liver pain, liver Swelling, tenderness, lower extremity edema often coincides with abdominal, lower chest and superficial varicose veins. For the diagnosis of this disease, about one third of patients have jaundice and splenomegaly.

3. Chronic phase: Except for some patients from the acute phase to the chronic phase, most patients have insidious onset, symptoms and signs slowly appear, begin to feel abdominal discomfort or abdominal distension, and then gradually liver enlargement, ascites and abdominal wall vein Expansion, a small number of patients with mild jaundice, the course can go through months or years, patients with very long illness, splenomegaly and esophageal varices, even hematemesis and melena, patients with inferior vena cava obstruction, chest, abdominal wall Venous engorgement is very obvious, the blood flow direction is from bottom to top, bilateral lower extremity edema, calf pigment spots on the calf skin, severe varicose veins in the lower limbs, and even nutrient ulcers in the ankle and foot, and elevated venous pressure in both lower extremities.

Examine

Examination of Bad Gayley syndrome

1. Liver function: Acute type of ALT, AST increased, serum bilirubin increased, serum protein decreased, prothrombin time prolonged, some patients have elevated ALP, subacute liver function can be basically normal or mild abnormalities, Chronic liver function changes are similar to cirrhosis.

2. Hematology: Acute blood tests may have elevated white blood cells, some patients have plethora, manifested as hematocrit and hemoglobin increase, subacute and chronic, in addition to dominant polycythemia, generally no significant changes.

3. Ascites examination: Ascites protein concentration in BCS often reaches 2.5 ~ 3.0g / L, can also be lower than this value, and there is a corresponding change in spontaneous peritonitis.

4. Ultrasound examination

(1) Abdominal B-ultrasound: Abdominal B-ultrasound examination is a simple, safe and effective method, which can make a correct diagnosis for most patients. The diagnostic compliance rate can reach 94.4%, which is often the preferred method of examination for this disease. The blood vessels involved in the disease are described below.

1 Hepatic vein changes: The blocked hepatic vein can be one or more, the performance of which depends on the extent and extent of obstruction, as follows:

A. Inferior vena cava obstruction of the hepatic segment: obstruction of the inferior vena cava above the hepatic vein opening, obstruction of hepatic venous return, widening of the hepatic vein, internal diameter >1.0 cm, stagnant blood flow in the lumen, see "spontaneous development" phenomenon, CDFI: The venous blood flow direction and flow rate are abnormal.

B. Membranous obstruction: often located in the opening of the hepatic vein, there is a membrane-like, strip-like echo, the inner diameter of the hepatic vein is widened, and there is uneven thickness between the hepatic vein and the unobstructed traffic, CDFI : The blood flow in the diaphragm is disordered, the flow rate is increased, and the spectrum is abnormal.

C. Embolization: including thrombosis and tumor thrombus, low-to-medium substantial echo in the hepatic vein, CDFI: no blood flow signal or blood flow reversal in the hepatic vein.

D. External pressure stenosis and occlusion: adjacent to the visible compression mass, the unobstructed diameter of the hepatic vein is normal or the hepatic vein blocked by the reflux is compensatory dilatation, the echo in the cavity is normal, and the blood flow is smooth.

2 inferior vena cava changes:

A. Inferior vena cava membranous obstruction: In the inferior vena cava of the hepatic segment or into the right atrium, see the "line-like" and "equal" strong echoes, and the phenomenon of "spontaneous development" is also seen in the lumen.

B. Embolism formation: a low-medium substantial echo in the hepatic vein.

C. External pressure inferior vena cava narrowing: due to the obvious increase in caudal lobe congestion.

D. Common manifestations of obstruction of inferior vena cava: the distal segment of the inferior vena cava has different degrees of dilatation, the inner diameter is >2.4cm, CDFI: no blood flow signal in the occlusion segment, narrowing of the blood flow in the stenosis, filling defect, loss of normal three Phase wave form, replaced by high-speed turbulence.

(2) Doppler ultrasound: Doppler ultrasound has extremely important diagnostic value for BCS.

1 Doppler ultrasound can accurately determine whether there is blood flow signal, if the hepatic venous blood flow signal disappears, there is definitely a blockage.

2 Doppler ultrasound can accurately determine the direction of blood flow, if the hepatic vein is reversed, it is also confirmed that there is obstruction at the entrance of the inferior vena cava.

3 hepatic vein Doppler wave pattern changes, normal, hepatic venous blood flow is phase, blood flow spectrum changes with cardiac cycle, the ratio of maximum blood flow velocity and minimum blood flow velocity is often greater than 4.0, if this time The phase change disappears and appears as advection or steady flow, suggesting obstruction at the entrance of the inferior vena cava or hepatic vein, but this change lacks characteristics. When cirrhosis occurs, 81.3% can show similar changes, and if there is inferior vena cava The blood flow in the middle and lower sections can also be diagnosed.

5. CT examination of CT can identify the hepatic vein, the obstruction of the inferior vena cava is congenital abnormality or secondary to tumor, thrombosis or other factors, as well as ascites, collateral circulation and other signs can be found, the CT examination is not able to show The vena cava diaphragm, while the medial branch of the liver is not as good as ultrasound and MRI.

(1) CT scan:

1 Large liver, especially one of the characteristics of hepatic caudal lobe enlargement, which is related to the direct return of the caudate lobe to the inferior vena cava.

2 The density of the peripheral part of the liver is low, and the density of the central part of the caudate lobe and the left lobe of the liver is relatively high.

3 can see ascites.

(2) CT enhancement:

1 In the early stage, the caudate lobe and the central part of the left lobe of the liver were rapidly strengthened. The high density of the fan-shaped distribution centered on the inferior vena cava of the hepatic segment, the edge was blurred, and then the opposite was performed, that is, the peripheral part showed delayed enhancement, caudate lobe and liver. The central part of the left lobe is cleared faster, which is related to the obstruction of hepatic venous return, and the compensatory increase of hepatic blood flow in the caudate lobe and part of the inferior vena cava.

2 The liver is patchy-like, and regional or extensive density inequality is one of its characteristics.

3 The hepatic vein is not strengthened, the continuous interruption between the hepatic vein and the inferior vena cava, the inferior vena cava of the hepatic segment, the hepatic vein embolization, the intraluminal filling defect during thrombosis, and the enlargement of the hepatic caudal lobe can cause the inferior vena cava of the hepatic segment. The fissure-like, inferior vena cava expansion below the occlusion end is rounded, and if the medial collateral circulation is established, the dilated hepatic vein or collateral venous branch can be shown.

4 can show dilated lateral hepatic veins, such as azygous, semi-singular and lumbar ascending veins.

MRI examination MRI has multi-planar, vascular flow effect, non-invasive features, can show hepatic vein, inferior vena cava, hepatic vein, obstruction of the inferior vena cava is congenital abnormality or secondary to tumor, thrombosis or other factors It can also be found that ascites, collateral circulation and other signs, the deficiency is sometimes difficult to identify slow blood flow and thrombosis, can not determine the direction of blood flow.

(1) Liver enlargement and liver signal changes. The signal intensity of the caudate lobe on the T2-weighted image is lower than that of other tissues because the blood flow of the caudate lobe is directly introduced into the inferior vena cava. When the hepatic venous return is blocked, the caudate lobe is generally Not tired or involved.

(2) hepatic vein, abnormal shape of inferior vena cava, hepatic vein stenosis or occlusion, hepatic vein and inferior vena cava are not connected, and the inferior vena cava of the hepatic segment is obviously narrow or obstructed, which may show the inferior vena cava septum and obstruction section, below the obstruction end Inferior vena cava dilatation, slower blood flow velocity can be a strong and weak signal, hepatic vein and inferior vena cava thrombosis, soft tissue high signal, sagittal plane, coronal imaging can show its range, hepatic medial branch blood vessel formation, It is "comic" or "spider web", and it is disorderly.

(3) With ascites, the low signal around the liver on the T1-weighted image and the high signal on the T2-weighted image.

(4) Liver, paravertebral space, abdominal wall veins with compensatory dilatation and low signal, and azygotic vein expansion.

(5) The anatomical structure of the inferior vena cava and right atrium can be clearly displayed, providing important preoperative information for the diagnosis of this disease.

7. Angiography: Angiography is the most important method to determine the location of BCS lesions. The following three methods can be used to understand the morphology and hemodynamic changes of hepatic veins and inferior vena cava.

(1) Intubation of the inferior vena cava through the femoral vein: When the inferior vena cava is completely obstructed, the catheter cannot enter the normal distance, and the impedance gradually appears upward. The pressure of the inferior vena cava is significantly increased when the manometry is under pressure; if there is obstruction of the inferior vena cava, At the same time, the jugular vein cannula can be used for two-way angiography, which can clearly show the shape of the membranous structure and the length of the obstruction distance. At this time, the wall thrombus can be seen below the obstruction site, and the distorted and dilated lumbar vein can be clearly displayed. Lumbar ascending vein, anterior spinal vein, iliac vein and pericardial iliac vein, blood flow through the azygous vein, visible one or two hepatic vein obstruction, obstruction of the lower segment of expansion, or a blockage, another compensatory expansion It can also be seen that the shunts between the various hepatic veins, if there is no obstruction of the inferior vena cava, the catheter of the skilled person can not enter the vein, suggesting that the hepatic vein is obstructed.

(2) transhepatic venous intubation: hepatic vein occlusion is best performed by hepatic vein intubation pressure and angiography. At this time, hepatic venous pressure is significantly increased. Injecting contrast agent can show the infarct location, degree, morphology, and visible hepatic vein. Various collateral circulations direct blood into the right atrium or reflux portal vein. The intrahepatic vessels are spider-like. At this time, if the inferior vena cava angiography is performed at the same time, the hepatic vein involvement can be more clearly understood, even through the hepatic vein. Intubation can not be successful, liver parenchyma can also be clearly diagnosed, but patients with severe bleeding tendency and a large number of ascites, contraindications to liver parenchyma.

(3) Celiac artery and superior mesenteric artery angiography and indirect portal vein angiography: selective angiography can also be used to confirm the diagnosis. At this time, the narrow and straight hepatic artery, high-density capillary shadow and portal vein blood flow can often be displayed.

8.99Tc liver scan: 99Tc liver scan diagnosis BCS features liver enlargement, morphological abnormalities, tracer aggregation in the hypertrophic hepatic caudate lobe, showing a "central concentration" phenomenon, the liver right lobe tracer is sparse Distribution or significant reduction, some patients, moderate or severe development and enlargement of the spleen.

9. Endoscopy: Gastroscope can only detect esophageal-gastric varices, which is of little help to the diagnosis of BCS. Laparoscopy is of great significance for the diagnosis of BCS. The liver is swollen under the microscope, the surface is smooth, and the appearance is purple. The biopsy under direct vision can confirm the diagnosis.

10. Liver biopsy: Liver histology can show characteristic changes in BCS. As long as clinical symptoms exclude cardiogenic factors, liver biopsy can generally make a definite diagnosis. However, this test cannot determine the nature, location and extent of obstruction. Instead of angiography, there is a certain risk of liver puncture when there is a serious bleeding tendency and a large amount of ascites, so it is not suitable for routine examination before surgery.

Diagnosis

Diagnostic identification of Bad Gyari syndrome

Acute BCS mostly has abdominal pain, hepatomegaly tenderness and ascites triad. Chronic patients have hepatomegaly, portal collateral circulation and ascites triad. Real-time ultrasound and Doppler ultrasound can prompt BCS diagnosis for more than 85% of patients. The diagnosis of BCS relies on hepatic vein and/or inferior vena cava angiography and liver biopsy.

Differential diagnosis

1. Acute hepatitis BCS must be distinguished from acute hepatitis:

(1) Acute BCS abdominal pain is severe, liver enlargement and tenderness are very obvious, and the jugular vein is filled, and the liver and neck reflux sign is negative.

(2) The appearance and growth rate of ascites and lower extremity edema are not proportional to changes in liver function.

(3) The patient has no history of exposure to viral hepatitis or hepatotoxic drugs or poisons, and the pathogenic examination of viral hepatitis is mostly negative.

(4) Liver biopsy is not a balloon-like eosinophilic change and point-like necrosis, but hemorrhagic necrosis in the central lobe of the lobes with obvious expansion of the hepatic sinus and hepatic venous thrombosis at all levels.

(5) Angiography can clearly distinguish the two.

2. Acute severe hepatitis (fullinant hepatitis) The following points contribute to the difference between acute severe hepatitis and fulminant BCS:

(1) fulminant BCS can not shrink or shrink the liver is not obvious, accompanied by a rapid increase in the spleen and obvious filling of the jugular vein.

(2) ALT, AST and serum bilirubin were significantly elevated in BCS, and there was no separation of enzymes.

(3) The pathogenic examination related to viral hepatitis at BCS is mostly negative.

(4) Liver biopsy at BCS showed flaky hemorrhagic necrosis in the liver, involving hepatic alveolar bands, and thrombus was seen in hepatic veins at all levels.

(5) Timely angiography can confirm the diagnosis.

3. Cirrhosis subacute or chronic BCS is often accompanied by cirrhosis, and patients with cirrhosis can also be associated with BCS. Therefore, determining whether a patient has BCS is critical to the choice of treatment. The identification methods are:

(1) Most of the BCS did not have a history of acute hepatitis, and even if there was jaundice in the course of the disease, most of them were accompanied by ascites.

(2) Physical examination is an important method to identify cirrhosis and BCS. In cirrhosis, the abdominal wall veins are arranged in a eccentric manner around the umbilicus. The drainage direction is also eccentric. In BCS, the lower chest, the two ribs and the lower back appear. Varicose veins, MOVC when the blood flow direction from bottom to top, simple hepatic vein obstruction when the blood flow direction from top to bottom, lower extremity edema with ulcer formation, hyperpigmentation or varicose support MOVC.

(3) Hepatic vein and / or inferior vena cava angiography and liver biopsy can confirm the diagnosis.

Subacute and chronic BCS are very similar to cardiogenic cirrhosis. Liver biopsy does not help to distinguish between the two, but the latter has a history and evidence of long-term right heart failure or constrictive pericarditis, as long as the heart and collateral circulation are carefully examined. Signs, no more difficult to differentiate diagnosis.

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