Portal Vein ThrombosisPortal Vein ThrombosisSophia A. Virani, HMS IIISophia A. Virani, HMS III

Gillian Lieberman, MDGillian Lieberman, MDBeth Israel Deaconess Medical CenterBeth Israel Deaconess Medical Center

Department of RadiologyDepartment of RadiologyMarch 2009March 2009

AgendaAgenda

Introduce index patientIntroduce index patient

Discuss portal vein thrombosis (PVT)Discuss portal vein thrombosis (PVT)

EtiologyEtiology

Menu of radiologic testsMenu of radiologic tests

ComplicationsComplications

Review hepatic anatomy and vasculature Review hepatic anatomy and vasculature

Companion CasesCompanion Cases

Review various treatment optionsReview various treatment options

LetLet’’s meet our patient s meet our patient ……

Ms. S: Initial presentationMs. S: Initial presentation

Ms. S is a 61 year old woman with ulcerative colitis and Ms. S is a 61 year old woman with ulcerative colitis and primary biliary cirrhosis (PBC) who was transferred from an primary biliary cirrhosis (PBC) who was transferred from an outside hospital with worsening abdominal pain, bloody outside hospital with worsening abdominal pain, bloody diarrhea and diarrhea and ascitesascites

Her ulcerative colitis had become steroidHer ulcerative colitis had become steroid--unresponsive during the unresponsive during the weeks prior to admissionweeks prior to admission

She has had PBC for ten years and her illness has been complicatShe has had PBC for ten years and her illness has been complicated ed by ascites and hepatic encephalopathyby ascites and hepatic encephalopathy

A review of her outside hospital CT showed a possible portal A review of her outside hospital CT showed a possible portal vein thrombusvein thrombus

Portal Vein Thrombus: OverviewPortal Vein Thrombus: Overview

Rare event but can have serious clinical consequencesRare event but can have serious clinical consequences

TypesTypes

Acute or chronicAcute or chronic

Bland or malignantBland or malignant

PresentationPresentation

Often subtle or asymptomaticOften subtle or asymptomatic►►

Symptoms are often those of primary illnessSymptoms are often those of primary illness

GI bleeding, abdominal pain, GI bleeding, abdominal pain, varicesvarices, , ascitesascites and and splenomegalysplenomegaly

In symptomatic patients, In symptomatic patients, varicealvariceal bleeding is the most common presentation bleeding is the most common presentation

ComplicationsComplications

Portal hypertension from increased pressure to portal vein obstrPortal hypertension from increased pressure to portal vein obstructionuction

Thrombus can spread to Thrombus can spread to splanchnicsplanchnic veins and potentially veins and potentially cause mesenteric ischemia, cause mesenteric ischemia, which is a surgical emergencywhich is a surgical emergency

High clinical suspicion and effective interpretation of High clinical suspicion and effective interpretation of radiologic findings are key to making the diagnosis of portal veradiologic findings are key to making the diagnosis of portal vein thrombusin thrombus

Etiology of Portal Vein ThrombusEtiology of Portal Vein Thrombus

Cirrhosis Cirrhosis

25% of patients with PVT have cirrhosis25% of patients with PVT have cirrhosis►►

1% of patients with cirrhosis develop PVT1% of patients with cirrhosis develop PVT►►

Likelihood of developing thrombus is associated with severity ofLikelihood of developing thrombus is associated with severity of diseasedisease

Stasis of flow in portal system predisposes to clot formationStasis of flow in portal system predisposes to clot formation

Deficiency of protein C, protein S and antithrombin III lead to Deficiency of protein C, protein S and antithrombin III lead to a a hypercoagulablehypercoagulable statestate

MalignancyMalignancy

HepatocellularHepatocellular carcinoma (HCC), pancreatic cancercarcinoma (HCC), pancreatic cancer

Development of thrombus is a poor prognostic factor in HCCDevelopment of thrombus is a poor prognostic factor in HCC

Hypercoagulable statesHypercoagulable states

Factor V Leiden, Prothrombin gene mutation, Protein C deficiencyFactor V Leiden, Prothrombin gene mutation, Protein C deficiency, Protein S , Protein S deficiency, Antithrombin III deficiencydeficiency, Antithrombin III deficiency

Myeloproliferative diseaseMyeloproliferative disease

InfectionInfection

Rare cause of PVTRare cause of PVT

IntraIntra--abdominal infection such as diverticulitis and appendicitis can abdominal infection such as diverticulitis and appendicitis can cause a cause a pylephlebitis of portal veinpylephlebitis of portal vein

In the pediatric population, omphalitis (infection of umbilical In the pediatric population, omphalitis (infection of umbilical stump) can spread to stump) can spread to portal veinportal vein

Post surgicalPost surgical

Post Post splenectomysplenectomy

Post transplant, secondary to surgical manipulation of portal syPost transplant, secondary to surgical manipulation of portal systemstem

Often multifactorialOften multifactorialEtiology unknown in up to 1/3 of casesEtiology unknown in up to 1/3 of cases

Portal vein thrombosis is a Portal vein thrombosis is a radiologic radiologic diagnosis. diagnosis.

LetLet’’s take a look at the various s take a look at the various options for imaging options for imaging ……..

PVT: Menu of Radiologic TestsPVT: Menu of Radiologic TestsTestTest Indications & Indications &

FindingsFindingsAdvantagesAdvantages DisadvantagesDisadvantages

UltrasoundUltrasound Echogenic thrombusEchogenic thrombusNo blood flow on No blood flow on DopplerDoppler

Non invasiveNon invasiveReadily availableReadily available

Operator dependentOperator dependentAcute thrombi could be Acute thrombi could be hypoechoic or anechoichypoechoic or anechoicDifficult to assess splenic vein Difficult to assess splenic vein and other branches due to and other branches due to background liver echogenicitybackground liver echogenicity

Contrast CTContrast CT NonNon--enhancing filling enhancing filling defect within lumendefect within lumenRim enhancementRim enhancementVariations with phase Variations with phase

Readily availableReadily availableNon operator Non operator dependent dependent

Contraindicated in patients with Contraindicated in patients with contrast allergy, renal contrast allergy, renal insufficiencyinsufficiency

MRIMRI Can see increased signal Can see increased signal intensity on T2intensity on T2

Non invasiveNon invasiveNo contrastNo contrast

ExpenseExpenseClaustrophobiaClaustrophobiaAscites may cause artifact Ascites may cause artifact

AngiographyAngiography Often preOften pre--operative or operative or during TIPSduring TIPSFilling defect Filling defect

Gold standardGold standardShows extent, location Shows extent, location and severity of and severity of thrombusthrombus

InvasiveInvasiveContrast Contrast

MRA / CTAMRA / CTA Filling defectFilling defect Good visualization of Good visualization of collateralscollaterals

InvasiveInvasiveContrast Contrast

Anatomy ReviewAnatomy Review

BIDMC PACSBIDMC PACSPortal Portal venogramvenogram showing main, left and showing main, left and right portal veinsright portal veins

Abdominal CT on admissionAbdominal CT on admission

BIDMC PACSBIDMC PACS

Ms. S: Patent Left Portal Vein and Left Portal Ms. S: Patent Left Portal Vein and Left Portal Vein thrombosis on CTVein thrombosis on CT

Abdominal CT 1 month prior Abdominal CT 1 month prior to admissionto admission

Left portal vein occlusion

C+ Abdominal CT, axial image, portal venous phase. BIDMC+ Abdominal CT, axial image, portal venous phase. BIDMC PACSC PACS

Patent left portal vein

**

**

**

**

* * ascitesascites

Portal Vein Thrombus: CT FindingsPortal Vein Thrombus: CT Findings

Non enhancing filling defect within lumenNon enhancing filling defect within lumen

Rim enhancementRim enhancement

Flow through dilated vasa vasorumFlow through dilated vasa vasorum

Increased flow around periphery of clotIncreased flow around periphery of clot

Can see phase dependent changesCan see phase dependent changes

Enhancement during arterial phase as hepatic artery compensates Enhancement during arterial phase as hepatic artery compensates for decreased blood flow from portal systemfor decreased blood flow from portal system

Decreased attenuation during portal venous phaseDecreased attenuation during portal venous phase

Occasionally can see calcifications in chronic thrombusOccasionally can see calcifications in chronic thrombus

Can see arterial phase enhancement if malignant thrombusCan see arterial phase enhancement if malignant thrombus

Ultrasound of Portal SystemUltrasound of Portal System

Can detect presence, direction and characteristics of portal Can detect presence, direction and characteristics of portal venous blood flowvenous blood flow

hepatopetalhepatopetal = flow toward liver= flow toward liver►► Normal direction of portal venous flowNormal direction of portal venous flow

hepatofugalhepatofugal = flow away from liver= flow away from liver

Normal portal venous flow is continuous Normal portal venous flow is continuous hepatopetalhepatopetal with with minimal respiratory variationminimal respiratory variation

HepatofugalHepatofugal flow in the portal system develops when flow in the portal system develops when pressure in portal system is greater than pressure in pressure in portal system is greater than pressure in collateral vesselscollateral vessels

Thrombus in portal vein would show absence of flow and Thrombus in portal vein would show absence of flow and an an echogenicechogenic thrombusthrombus

Ms. S: Patent Portal Vein on USMs. S: Patent Portal Vein on US

Transverse color doppler ultrasound of main portal vein

Flow depicts patent main portal vein

Transverse color doppler ultrasound of left portal vein

Flow depicts patent left portal vein

Possible small echogenic thrombus in left portal vein

Ms. S: Clinical CourseMs. S: Clinical Course

Ulcerative ColitisUlcerative Colitis

Treated with an infusion of Remicade, a TNFTreated with an infusion of Remicade, a TNF--

inhibitorinhibitor

Received 2 units packed red blood cellsReceived 2 units packed red blood cells

Primary Primary biliarybiliary cirrhosiscirrhosis

Developed hepatic encephalopathy Developed hepatic encephalopathy ►►

Treated with lactulose and Treated with lactulose and rifaximinrifaximin

Therapeutic Therapeutic paracentesisparacentesis

Tested positive for HIT antibodiesTested positive for HIT antibodies

Lower extremity ultrasound showed no Lower extremity ultrasound showed no DVTsDVTs

Acute PVTAcute PVT

Review of outside hospital CT showed left portal vein thrombusReview of outside hospital CT showed left portal vein thrombus

Doppler ultrasound revealed patent left portal vein, though nonDoppler ultrasound revealed patent left portal vein, though non--occlusive occlusive thrombus could not be ruled outthrombus could not be ruled out

Anticoagulation contraindicated given GI bleedingAnticoagulation contraindicated given GI bleeding

Scheduled for follow up CT in 2 weeksScheduled for follow up CT in 2 weeks

Represented within 2 weeks for acute decompensation of end Represented within 2 weeks for acute decompensation of end stage liver diseasestage liver disease

Ms. S underwent ultrasound and Ms. S underwent ultrasound and CT scans which showed CT scans which showed

progression of her portal vein progression of her portal vein thrombus.thrombus.

Ms. S: Portal Vein Thrombus on UltrasoundMs. S: Portal Vein Thrombus on Ultrasound

No flow in main portal veinNo flow in main portal veinEchogenic thrombusEchogenic thrombus

BIDMC PACSBIDMC PACS

Previous UltrasoundPrevious Ultrasound

BIDMC PACSBIDMC PACS

Next Step?

Color Color dopplerdoppler ultrasound, transverse view of liverultrasound, transverse view of liver

Ms. S: Main Portal Vein Thrombus on CTMs. S: Main Portal Vein Thrombus on CT

Non enhancing filling defect in main PV

Multiple collateral vessels

ascites

BIDMC PACSBIDMC PACS

**

**

**

**

Contrast enhanced abdominal CT, axial images, portal venous phaContrast enhanced abdominal CT, axial images, portal venous phasese

Ms. S: Left and Right Portal Vein Thrombi on CTMs. S: Left and Right Portal Vein Thrombi on CT

BIDMC PACSBIDMC PACS

Left portal vein occlusionLeft portal vein occlusion Right portal vein occlusionRight portal vein occlusion

Contrast enhanced abdominal CT, axial images, portal venous phaContrast enhanced abdominal CT, axial images, portal venous phasese

Ms. S: Superior Mesenteric Vein Thrombus on Ms. S: Superior Mesenteric Vein Thrombus on CTCT

BIDMC PACSBIDMC PACSContrast enhanced abdominal CT, axial images, portal venous phaContrast enhanced abdominal CT, axial images, portal venous phasese

Filling defect in superior mesenteric vein (SMV)

Ms. S: Main Portal Vein and SMV Thrombus on CTMs. S: Main Portal Vein and SMV Thrombus on CT

BIDMC PACSBIDMC PACS

Thrombus in main portal vein

Thrombus in SMV

Ascites

Multiple collateral vessels

**

**

**

Contrast enhanced abdominal CT, portal venous phase, maximum inContrast enhanced abdominal CT, portal venous phase, maximum intensity tensity projection, coronal reconstructionprojection, coronal reconstruction

Ms. S: Interim Clinical CourseMs. S: Interim Clinical Course

Acute liver failureAcute liver failure

MELD 28, up from 13 during last admissionMELD 28, up from 13 during last admission

Total bilirubin 16.4, up from 2.6 during last admissionTotal bilirubin 16.4, up from 2.6 during last admission

She developed a She developed a leukocytosisleukocytosis which was which was concerning for possible spontaneous bacterial concerning for possible spontaneous bacterial peritonitisperitonitis

Hypotensive and tachycardicHypotensive and tachycardic

Placement of central linePlacement of central line

She became hypoxic to 88% on RAShe became hypoxic to 88% on RA

Chest xChest x--ray to evaluate hypoxiaray to evaluate hypoxia

Ms. S: Ms. S: PneumothoraxPneumothorax and Pleural Effusion and Pleural Effusion on Chest Xon Chest X--RAYRAY

Right pleural effusion

Left pneumothorax

Collapsed left lung

Central line

possible cause of pneumothorax

Chest tubeChest tube

Chest tube with re-expanded left lung

BIDMC PACSBIDMC PACS

******

Portable anteriorPortable anterior--posterior chest xposterior chest x--rayray

Ms. S: Clinical ProgressionMs. S: Clinical Progression

Significant clinical Significant clinical decompensationdecompensation, most likely , most likely due to occlusive portal vein thrombusdue to occlusive portal vein thrombus

Anticoagulation contraindicated given GI bleedAnticoagulation contraindicated given GI bleed

The transplant team was consultedThe transplant team was consulted►►She was not a candidate for transplant because of her She was not a candidate for transplant because of her

ulcerative colitis and possible sepsisulcerative colitis and possible sepsis

She developed disseminated intravascular She developed disseminated intravascular coagulation and coagulation and methicillinmethicillin--resistentresistent staph staph aureusaureus bacteremiabacteremia

She was ultimately made comfort measures only She was ultimately made comfort measures only and passed away soon afterand passed away soon after

Ms. SMs. S’’s case demonstrated an s case demonstrated an acute, bland thrombus in the acute, bland thrombus in the

setting of cirrhosis.setting of cirrhosis.

LetLet’’s move on to see features of s move on to see features of portal vein thrombus caused by a portal vein thrombus caused by a tumor in two companion patientstumor in two companion patients

Companion Patient #1: Companion Patient #1: Portal Vein Tumor Thrombus on CTPortal Vein Tumor Thrombus on CT

71 year old male with a history of hepatitis B who presents with71 year old male with a history of hepatitis B who presents with two two days of epigastric pain, frequent bowel movements and fecal days of epigastric pain, frequent bowel movements and fecal incontinenceincontinence

BIDMC PACSBIDMC PACSC+ CT scan, axial images, portal venous phaseC+ CT scan, axial images, portal venous phase

Large hypoattenuating mass in right lobe of liver extending into portal vein

Tumor Thrombus: Radiologic FeaturesTumor Thrombus: Radiologic Features

Often see dilation of portal Often see dilation of portal vein vein

Diameter > 23mmDiameter > 23mm**

Intrathrombus neovascularityIntrathrombus neovascularity

Arterial enhancement on CTArterial enhancement on CT

Pulsatile flow on doppler USPulsatile flow on doppler US

““Thread and streak signThread and streak sign””

multiple enhancing multiple enhancing intraluminalintraluminal smaller vessels that can be seen smaller vessels that can be seen at arterial phase imagingat arterial phase imaging

Contiguity to tumor Contiguity to tumor

Often with direct invasionOften with direct invasion

**TublinTublin et al., et al., ““Benign and malignant portal vein thrombosis.Benign and malignant portal vein thrombosis.””

Companion patient #1Companion patient #1

BIDMC PACSBIDMC PACS

Companion Patient #1: Companion Patient #1: Inferior Vena Cava and Right Inferior Vena Cava and Right AtrialAtrial Thrombi on CTThrombi on CT

IVC tumor thrombusBIDMC PACSBIDMC PACS BIDMC PACSBIDMC PACS

Right atrial tumor thrombus

BIDMC PACSBIDMC PACS BIDMC PACSBIDMC PACS

Contrast enhanced abdominal CT, portal venous phase, maximum inContrast enhanced abdominal CT, portal venous phase, maximum intensity projection, coronal reconstructiontensity projection, coronal reconstruction

Companion Patient #2: Companion Patient #2: PVT and Cavernous Transformation on CTPVT and Cavernous Transformation on CT

52 year old male with a three year history of renal cell carcino52 year old male with a three year history of renal cell carcinoma with ma with liver metastases and known left portal vein thrombusliver metastases and known left portal vein thrombus

Left portal vein thrombus

Multiple hypoattenuating lesions consistent with metastatic disease

Multiple serpiginous periportal collateral vessels = CAVERNOUS TRANSFORMATION

Cavernous TransformationCavernous Transformation

Formation of multiple venous collaterals when portal Formation of multiple venous collaterals when portal system is obstructedsystem is obstructed

Necessary to drain tributaries of portal vein and maintain adequNecessary to drain tributaries of portal vein and maintain adequate hepatic ate hepatic perfusionperfusion

Can be Can be portoporto--portoporto (bypassing obstruction) or (bypassing obstruction) or portoporto--systemicsystemic

Good imaging of collaterals is important for surgical Good imaging of collaterals is important for surgical

planningplanning

Imaging techniquesImaging techniques

CT, US, MRI, CTA, MRACT, US, MRI, CTA, MRA

Appearance: spongelike, serpiginous, corkscrew, netlikeAppearance: spongelike, serpiginous, corkscrew, netlike

Collateral CirculationCollateral Circulation

Reversal of flow into low pressure collateral veins due to Reversal of flow into low pressure collateral veins due to portal hypertensionportal hypertension

Major Major portoporto--systemic collateralssystemic collaterals

Left gastric vein, short gastric veins, esophageal veinsLeft gastric vein, short gastric veins, esophageal veins►► Anastomose with azygous systemAnastomose with azygous system►► Esophageal varicesEsophageal varices

ParaPara--umbilical and abdominal wall veinsumbilical and abdominal wall veins►► Caput medusaCaput medusa

Splenorenal shuntsSplenorenal shunts

Rectal Rectal varicesvarices

Bleeding from varices causes significant morbidityBleeding from varices causes significant morbidity

Companion Patient #3: Companion Patient #3: PortoPorto--Porto Collaterals on CT and MRAPorto Collaterals on CT and MRA

Wang et. al Wang et. al ““Cavernous transformation of the portal vein: Cavernous transformation of the portal vein: 3D dynamic contrast enhanced MR angiography3D dynamic contrast enhanced MR angiography””

Lee et al: Lee et al: Portal vein thrombosis: CT featuresPortal vein thrombosis: CT features

Cavernous transformation on Cavernous transformation on contrast enhanced CT scan, contrast enhanced CT scan, portal venous phaseportal venous phase

Cavernous transformation on MRI Cavernous transformation on MRI angiographyangiography

Companion Patient #4: Cirrhosis on CT scanCompanion Patient #4: Cirrhosis on CT scan

57 year old male with a history of alcoholic cirrhosis, portal 57 year old male with a history of alcoholic cirrhosis, portal hypertension, gastroesophageal varices and chronic portal vein hypertension, gastroesophageal varices and chronic portal vein thrombosisthrombosis

Presented for possible Presented for possible transjugalartransjugalar intrahepaticintrahepatic portoporto--systemic shunt systemic shunt (TIPS) procedure to alleviate portal hypertension(TIPS) procedure to alleviate portal hypertension

Shrunken, cirrhotic liver

BIDMC PACSBIDMC PACS

The patient had a The patient had a percutaneouspercutaneous venogramvenogram to visualize the portal to visualize the portal system during his TIPS attemptsystem during his TIPS attempt

Companion Patient #4: Portal Vein Thrombus Companion Patient #4: Portal Vein Thrombus on on PercutaneousPercutaneous VenogramVenogram

Blocked Blocked main portal main portal veinvein

Large Large splenic splenic collateral to collateral to left and left and right portal right portal veins veins effectively effectively replacing replacing main portal main portal veinvein

BIDMC PACSBIDMC PACS

Treatment Modalities for PVTTreatment Modalities for PVT

Treatment dependent on nature of clotTreatment dependent on nature of clot

Acute, recent or chronicAcute, recent or chronic

Treat for Treat for varicesvarices with with sclerotherapysclerotherapy or bandingor banding

Direct Direct thrombolysisthrombolysis with with tPAtPA or streptokinase in acute clotor streptokinase in acute clot

LongLong--term anticoagulationterm anticoagulation

At least three months, longer if underlying At least three months, longer if underlying hypercoagulablehypercoagulable statestate

Mechanical Mechanical thrombectomythrombectomy

TIPSTIPS

ControversialControversial►►

Contraindicated if complete occlusion or significant cavernous tContraindicated if complete occlusion or significant cavernous transformationransformation

Can reduce risk of variceal bleedingCan reduce risk of variceal bleeding

Often in conjunction with mechanical thrombectomy or direct throOften in conjunction with mechanical thrombectomy or direct thrombolysismbolysis

Indications: failed Indications: failed sclerotherapysclerotherapy, , ascitesascites, pre, pre--operativeoperative

Risk of embolismRisk of embolism

SummarySummary

Portal vein thrombus is rare in the general Portal vein thrombus is rare in the general population but not rare in the cirrhotic population but not rare in the cirrhotic populationpopulation

Often asymptomaticOften asymptomatic

Consider workup in a patient with Consider workup in a patient with varicealvariceal bleed, new bleed, new ascitesascites or sudden or sudden decompensationdecompensation in a patient with cirrhosisin a patient with cirrhosis

Ultrasound and CT are first line for Ultrasound and CT are first line for diagnosisdiagnosis

AcknowledgmentsAcknowledgments

Brian Midkiff, MDBrian Midkiff, MD

Martin Smith, MDMartin Smith, MD

SalamaoSalamao Faintuch, MDFaintuch, MD

Erica Gupta, MDErica Gupta, MD

Sadhna Nandwana, MDSadhna Nandwana, MD

Gillian Lieberman, MDGillian Lieberman, MD

Maria LevantakisMaria Levantakis

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