Vascular Liver Diseases Flashcards
What are the 3 categories of obstruction of the venous system of the liver
Veno-occlusive disease
Budd-Chiari syndrome
Congestive hepatopathy
Where does the liver arise from embryologically
A diverticulum on the ventral surface gut
What are the 3 vessels of the liver
Hepatic Artery
Hepatic Vein
Hepatic Portal Vein
What is the function of the hepatic veins
To convey the blood away from the liver
What do the hepatic veins converge to form
Three large trunks draining into the inferior vena cava
What is the substance of the liver composed of
Lobules
What does each lobule consist of
A mass of hepatic cells, arranged in irregular radiating columns between which are the blood channels (sinusoids
What is the function of the sinusoids
T convey the blood from the circumference to the centre of the lobule ending in the intralobular vein
What does the intralobular vein drain into
The sublobular vein
What does the intralobular vein drain into
The sublobular vein
What is Budd-Chiari sundrome
An uncommon and potentially life-threatening condition
What causes Budd-Chiari syndrome
The obstruction of hepatic venous outflow at any level from the small hepatic veins to the junction of the IVC with the right atrium
BCS is more common in women. True or False
True
What is the commonest cause of of BCS
Intraluminal thrombosis
What are some of the other causes of BCS
Malignancy
Parasites
Abscess or cyst
vascular webs
how do the pathological features of BCS result
From the increased sinusoidal pressure that occurs with hepatic venous obstruction
Reduced venous perfusion and congestion result in what
Hypoxic damage to the liver parenchymal cells, releasing free radicals
What happens if the sinusoidal pressure is reduced
The liver function improves
What are the clinical features of BCS
Ascites
Hepatomegaly
abdominal pain
What has resulted in a decrease in mortality for BCS patients
Introduction of anticoagulation and earlier recognition of asymptomatic disease
What might also be present if IVC compression or thrombosis causes the disease
Leg oedema or venous collateral over the trunk and back
What is the diagnosis of BCS dependent on
Imaging:
Doppler US - shows hepatic vein obstruction or abnormal flow in large intrahepatic or subcapsular venous collaterals
Contrast CT allows assessment for parenchymal disease, ascites and splenomegaly
What is seen pathologically in BCS
A variable degree of parenchymal damage dependent on the location and extent of venous congestion
What is characteristic in the perivenular areas in BCS
Ischaemic necrosis and fibrosis
What are the 3 main aims of managing BCS
Alleviate the obstruction
Prevent extension of thrombosis
Preserve hepatic function by decreasing centrilobular congestion
What is involved in the medical management of BCS
Control the ascites (low sodium diet, diuretics or paracentesis
Prevent thrombosis extension (anticoagulation)
Treat complications
Investigate and treat underlying cause
How might restoration of hepatic blood flow be achieved by
Thrombolytic therapy (fresh thrombus)
Percutaneous angioplasty
Transjugular intrahepatic portosystemic shunt (TIPS)
Portosystemic shunt surgery
What does TIPS do
Provides an alternative venous outflow tract to decompress the liver
Useful as a bridge to liver transplantation and in acute situations
What does TIPS do
Provides an alternative venous outflow tract to decompress the liver
Useful as a bridge to liver transplantation and in acute situations
Why is a liver biopsy not accurate in determining the prognosis of BCS
There is an uneven distribution of hepatic lesions in BCS
Why is a liver biopsy not accurate in determining the prognosis of BCS
There is an uneven distribution of hepatic lesions in BCS
What is Hepatic Veno-occlusive disease
It typically occurs after heamatopoietic stem cell transplantation but also after ingestion of pyrrolizidine alkaloids
What are the histological features of Veno-occlusive disease
Loss of sinusoidal endothelial cell
appearance of gaps in the SEC barrier
Narrowing of the sublobular and venous lumena become obliterated
What are some of the clinical features of Veno-occlusive disease
signs are symptoms develop within 3 weeks of exposure in the case of HSCT and primary those of tender hepatomegaly, fluids retention ascites jaundice RUQ pain
What are the risk factors for the development of VOD
Advanced age
Presence of liver injury prior to HSCT
Clotting cascade mutations
What is the fold standard investigation for VOD
Liver biopsy
What is the preventative measures against VOD
modifying the conditioning regimen in patients at increased risk of VOD
Use of ursodeoxycholic acid as prophylaxis
Heparin infusion may be useful but risk of bleeding is high
What is the treatment for VOD
Simply diuretics and sodium restriction
Repeated paracentesis may be required
What should be avoided in VOD
Hepatotoxic drugs
What is portal vein thrombosis
Occurs most commonly as a complication of cirrhosiss, particularly in decompensated disease
What are the 4 anatomical categories for PVT
Thrombus confined to the portal vein beyond confluence with the SMV
Extension into the SMV but patent mesenteric vessels
Diffuse splanchnic venous involvement with large collaterals
Splanchnic involvement but extensive fine collaterals
What are the 4 anatomical categories for PVT
Thrombus confined to the portal vein beyond confluence with the SMV
Extension into the SMV but patent mesenteric vessels
Diffuse splanchnic venous involvement with large collaterals
Splanchnic involvement but extensive fine collaterals
What does Portal cavernoma formation or cavernous transformation of the portal vein result from
The development of multiple small vessels in and around the recanalising or occluded main portal vein
What are some of the clinical features of a portal vein thrombosis
Acute: onset is suggested by the absence of clinical, endoscopic and radiological evidence of portal hypertension, typically thrombosis occurring
What is the most common complication of PVT
Variceal bleeding
What are the investigations required in PVT
Doppler ultrasound
Contrast CT
What is the management in PVT
Reserve or prevent the advancement of thrombosis and to treat the complications
How is variceal bleeding managed
Endoscopic therapy / medical therapy including non-selective B blockers and nitrates
What might be of benefit where splenomegaly causes hypersplenism
Splenectomy
What are the 5 main causes of congestive hepatopathy and cardiac cirrhosis
Ischaemic heart disease Cardiomyopathy Valvular heart disease Restrictive lung disease Pericardial disease
What is the classical pathological description of congestive hepatopathy and cardiac cirrhosis
Nutmeg liver
What are the clinical features of congestive hepatopathy and cardiac cirrhosis
Liver dysfunction is mild and asymptomatic
mild jaundice and RUQ pain in more severe congestion
What are the clinical features of congestive hepatopathy and cardiac cirrhosis
Liver dysfunction is mild and asymptomatic
mild jaundice and RUQ pain in more severe congestion
What are the symptoms of congestive hepatopathy and cardiac cirrhosis
Exertional dyspnoea
orthopnoea
angina
Presence of what murmur may make the liver pulsatile
Tricuspid regurgitation
What investigations are carried out for congestive hepatopathy and cardiac cirrhosis
Liver biochemistry:
Hyperbilirubinaemia is mostly unconjugated
Alkaline phosphatase is only mildly elevated
Viral hepatitis serology
Abdominal US with Doppler studies of the liver
Liver biopsy
ECG and Echo
What is the management for congestive hepatopathy and cardiac cirrhosis
Treating the underlying heart disease
Diuresis for jaundice and ascites
Liver cell injury resulting from subcritical supply of oxygen to hepatocytes is traditionally classified as what 2 things
Inadequate blood supply due to reduced hepatic arterial flow and or passive venous congestion (heart failure) termed ischaemic hepatitis Hypoxic insult (respiratory failure) termed hypxoc hepatitis
What is the final common pathway in ischaemic/ hypoxic hepatitis
Hepatocellular dysfunction secondary to critically low levels of oxygen for metabolic processes
Hypoxic injury to the liver is not reversible. True or false.
False- it is reversible
What are the 5 main aetiologies for hypoxic hepatitis
Primary heart disease Congestive heart failure Acute MI Chronic respiratory failure Circulatory shock and sepsis
What results in increased oxygen consumption or decreased oxygen availability
Hypoperfusion
What are some of the histological findings in hypoxic hepatitis
central hepatic vein congestion with centrilobular hepatic necrosis fragmentation of liver bulks polymorphonuclear cell infiltration abnormal hepatocyte complexes pyknosis disintegration of hypatocyte nuclei
What are absent which are present in other forms of hepatitis
Hyperplasia
Inflammation
regeneration
What are the clinical features of hypoxic hepatitis
Nausea and vomiting
Tender and enlarged liver
What are risk factors for hypoxic hepatitis
Acute and chronic heart failure respiratory failure sepsis prolonged hypotension toxin ingestion Heat stroke
What are the investigations involved for Hypoxic hepatitis
Diagnosis is based on clinical and biochemical criteria generally without the need for procedural intervention
Transient serum enzyme elevation in conjunction with abnormal renal function and abnormalities in PT and APTT activity
What is the management for patients with Hypoxic hepatitis
Purely supportive and focuses on correcting the underlying conditions leading to hypotension and hypoxic and hepatic hypoperfusion
