arteriovenous malformations in osler weber rendu: a...

Arteriovenous

Malformations in  Osler Weber‐Rendu: 

A Patient StudyKush M Parmar,  Harvard Medical School Year III

Gillian Lieberman, MD

Kush M Parmar, HMS IIIGillian Lieberman, MD

September 2008

Objectives

Kush M Parmar, HMS IIIGillian Lieberman, MD

• Learn what an arteriovenous

malformation (AVM) is.

• Learn imaging modalities that can be used to image AVM.

• Learn the typical appearance of AVM. 

• Appreciate the clinical manifestations of AVM in Osler‐Weber‐Rendu/HHT.

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Mrs. R: History

Kush M Parmar, HMS IIIGillian Lieberman, MD

3

• 37 y/o

woman w/ R. MCA ischemic stroke

• Coagulation studies were negative/normal

• No ASD/PFO (potential cause of paradoxical embolism)

• “Cryptogenic stroke”

presentation (no known cause) 

Mrs. R: AP CXR

Kush M Parmar, HMS IIIGillian Lieberman, MD

Rounded opacity at R. cardiophrenic angle

Linear opacity extending between rounded opacity and hilum

PACS/BIDMC

FINDINGS

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Findings suggestive of PAVM

Kush M Parmar, HMS IIIGillian Lieberman, MD

General Architecture of Arteriovenous

Malformations (AVM)

‐ Dilated, tortuous feeding and draining vessels ‐ A “nidus”

or “serpiginous”

mass of malformed vessels‐ Diminished oxygen diffusion (A‐V shunt); abnormal/absent capillary bed‐ Rapid filling and emptying

http://neuro.wehealny.org

5

Imaging Pulmonary AVM:  Menu of Tests

Kush M Parmar, HMS IIIGillian Lieberman, MD

•

Pulmonary angiography•

Used mainly for therapeutic 

interventions due to invasiveness

•

MR angiography

•

Chest CT (+/‐

C)

•

Gold standard

•

Chest X‐ray•

Only useful for large AVM

•

Transthoracic

Contrast Echo

•

Shunt quantification

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Features of Pulmonary AVM on  Chest X‐Ray

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Kush M Parmar, HMS IIIGillian Lieberman, MD

• Round or oval opacity• Uniform density, noncalcified• Often lobulated

but sharply 

defined• Location: frequently in lower lobes• Connection: may

show feeding 

artery radiating from hilus

PACS/BIDMC

Features of Pulmonary AVM on CT

• Homogeneous, non‐calcified, circumscribed 

nodule or serpiginous

mass

• MUST

have a direct feeding artery

– Dilated efferent draining vein• With contrast: 

– Sequential enhancement of feeding artery and 

aneurysmal

part– Early filling of draining vein (to differentiate from 

highly vascular soft tissue mass)

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Kush M Parmar, HMS IIIGillian Lieberman, MD

Mrs. R: Chest CT

9

Kush M Parmar, HMS IIIGillian Lieberman, MD

feeding branch of pulmonary artery

nidus

of AVM

R. hemidiaphragm

9

C+CT

Mrs. R: Decision to Embolize

With the clear determination of pulmonary  AVM on CT, it was decided to proceed with  therapeutic embolization. 

Kush M Parmar, HMS IIIGillian Lieberman, MD

10

11

Kush M Parmar, HMS IIIGillian Lieberman, MD

L. pulmonary artery

catheter in IVC

PACS/BIDMC

Mrs. R: Digital subtraction pulmonary  arteriogram

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(L. Lung, normal)

Mrs. R: Digital subtraction pulmonary  arteriogram

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Kush M Parmar, HMS IIIGillian Lieberman, MD

(R. Lung, before therapeutic embolism)

feeding artery

drainingvein

PACS/BIDMC

AVM

R. pulmonary artery

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Therapeutic Embolism of PAVM

13

Kush M Parmar, HMS IIIGillian Lieberman, MD

www.amplatzer.com

14

Mrs. R: Post‐embolizationKush M Parmar, HMS IIIGillian Lieberman, MD

Digital subtraction pulmonary arteriogram(R. Lung, post‐therapeutic embolism)

R. pulmonary artery

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15

Mrs. R: Post‐embolizationKush M Parmar, HMS IIIGillian Lieberman, MD

Digital subtraction pulmonary arteriogram(R. Lung, post‐therapeutic embolism)

R. pulmonary artery

pre-embolism

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AVM nidus

No filling in embolized

AVM

Differential Diagnosis of  Pulmonary AVM

Congenital (~90%)

• Hereditary Hemorrhagic Telangectasia(Osler‐Weber‐Rendu)

– Type I –

EDG1 mutations– Type II –

ALK1 mutations– Other

–

unmapped loci

Acquired

• Highly vascular parenchymal

lesion (compare kinetics 

with other vascular structure)16

Kush M Parmar, HMS IIIGillian Lieberman, MD

Clinical Manifestations of  Pulmonary AVM

• Dyspnea

on exertion• Hypoxemia

• Stroke• Transient ischemic attack • Cerebral abscess

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Kush M Parmar, HMS IIIGillian Lieberman, MD

Primary mechanism

right-left shunt

paradoxical embolism( our patient)

Most PAVM are asymptomatic for years, so many are first encountered incidentally on imaging

Screening for Pulmonary AVM in HHT Patients

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Chest Radiographs

Contrast echocardiography

-

-

+

+

Chest CT

Absence of PAVM

Prophylactic antibioticsto prevent brain abscess from paradoxical emboli

Absence of PAVM Positive PAVM

Kush M Parmar, HMS IIIGillian Lieberman, MD

+-

Hepatic AVM: Menu of Tests

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Kush M Parmar, HMS IIIGillian Lieberman, MD

•

Doppler Color Ultrasound (Echo Color Doppler)•

Low cost

•

No radiation

•

Highly sensitive

•

CT•

Specific, gold standard

Hepatic AVM on CTKush M Parmar, HMS IIIGillian Lieberman, MD

Early Arterial Phase Late Arterial Phase Portal Venous Phase

hepatic veins

AVM• AVM is most apparent in early arterial phase, no longer visible in portal venous phase

• Hepatic veins fill early

Buonamico et al. J Hepatol. 2008 ;48(5):811-2020

C+CT

21

•

Heterogenous

opacification

of liver 

‐ Due to many small hypervascular

spots (in HHT patients)

• Early arterial phase contrast filling of AVM

• Hepatic vein enhancement in early arterial                      

phase‐ Caused by AVM shunt

Hepatic AVM Features on CT

Kush M Parmar, HMS IIIGillian Lieberman, MD

21

•

Hypervascularization: tortuous hepatic arteries‐Highly visible main intrahepatic

branches of the hepatic artery in the 

portal spaces.‐Shunt determines tortuosity

and enlargement of these vessels. 

Hepatic AVM Features on US

Kush M Parmar, HMS IIIGillian Lieberman, MD

EPA=hepatic arteryPV=portal vein

Buonamico et al. J Hepatol. 2008 ;48(5):811-2022

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Hepatic AVM Features on US

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• Intrahepatic

“color spots”‐The presence of subcapsular

vascular spots near the hepatic 

capsule consisting mainly of arterial blood flow.

Buonamico et al. J Hepatol. 2008 ;48(5):811-20

Kush M Parmar, HMS IIIGillian Lieberman, MD

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Osler‐Weber‐Rendu/ Hereditary Hemorrhagic 

Telangiectasia

(HHT)• One of the most common monogenic diseases (~1 in 5000‐

10000)

• Progressive clinical manifestations over decades

• Epistaxis– Usually 1st

manifestation, ~10 yr of age

• Telangiectasia– Onset at ~3rd

decade of life– Lips, tongue, palate, fingers, and face

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Kush M Parmar, HMS IIIGillian Lieberman, MD

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Diagnosis of HHT

• Curacao criteria• Definite diagnosis with 3 out of 4 criteria

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Kush M Parmar, HMS IIIGillian Lieberman, MD

Criterium Description

Epistaxis Spontaneous, recurrent nose bleeds; often first 

manifestation

Telangiectasias Multiple, at characteristic sites: lips, oral cavity, 

fingers, nose 

Visceral lesions Gastrointestinal telangiectasias

(+/‐

bleeding)Pulmonary AVMHepatic AVMCerebral AVMSpinal AVM

Family history A first‐degree relative with HHT according to these 

criteria

25

Gossage

et al. Am J Respir

Crit

Care Med 1998; 158: 643‐661

Likely locations of AVM

26

Kush M Parmar, HMS IIIGillian Lieberman, MD

‐

lung‐ liver‐ brain‐ spinal cord‐ spleen‐

kidney

‐

spermatic cord

26

Osler‐Weber‐

Rendu/HHT

Idiopathic/Other

Imaging AVM: Summary

27

1. Menu of Tests to Image AVM is Organ‐specific• Pulmonary: CT, Angiography (for interventions)• Hepatic: CT, US

2. Typical architecture of AVM:• Entirely vascular structure that ‘shortcuts’

capillaries

• Dilated, tortuous feeding and draining vessels• Rapid filling and draining of contrast

Kush M Parmar, HMS IIIGillian Lieberman, MD

3. Detecting an AVM may provide an opportunity to     

pre‐emptively

address it and offer genetic counseling 

for Osler‐Weber‐Rendu

patients and their family

27

28

References

•

Cottin

V, Dupuis‐Girod

S, Gaetan

L, Cordier

J‐F. Pulmonary Vascular Manifestations of Hereditary 

Hemorrhagic Telangiectasia

(Rendu‐Osler Disease). Respiration

2007; 74:361‐378.

•

Gossage

JR, Kanj

G. Pulmonary Arteriovenous

Malformations: A State of the Art Review. Am J 

Respir

Crit

Care Med 1998; 158: 643‐661

•

Remy J, Remy‐Jardin

M, Wattine

L, Deffontaines

C. Pulmonary Arteriovenous

Malformations: 

Evaluation with CT of the Chest before and after Treatment. Radiology 1992; 182: 809‐816. 

•

Buonamico

P, Suppressa

P, Lenato

GM, Pasculli

G, D'Ovidio

F, Memeo

M, Scardapane

A, Sabbà

C. 

Liver involvement in a large cohort of patients with hereditary hemorrhagic telangiectasia: echo‐

color‐Doppler vs multislice

computed tomography study. J Hepatol. 2008 ;48(5):811‐20

Kush M Parmar, HMS IIIGillian Lieberman, MD

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Acknowledgements

• Salomao

Paintuch, MD

• Dmitri J Rabkin, MD

• Gillian Lieberman, MD

• Larry Barbaras (webmaster)

• Maria Levantakis

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Kush M Parmar, HMS IIIGillian Lieberman, MD

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