Radiologic Imaging and Treatment of Pulmonary AVMs

Deborah VintonGillian Lieberman M.D.

March 2008

Clinical Presentation of Pt A

• 34 yo female with acute onset of R sided hemiparesis and aphasia

Pt A: Head CT on Presentation

PACS, BIDMC

Head CT without contrast showed a hyperdense L MCA sign

Pt A: Occlusion of L MCA and ICA

Completed occluded L ICA and L MCA

PACS, BIDMC

Decreased blood flow in are of L MCA

PACS, BIDMC

Pt A Percutaneous Clot Retrieval

IA tPA administeredMERCI clot retriever deployed

http://www.med.cornell.edu/science/2006/03_ 06/03_06-2.shtml

Good flow achieved through L ICA and MCA

PACS, BIDMC

Angio revealed clot extending from L ICA into L MCA

PACS, BIDMC

Etiology of Thrombotic Infarct Most Likely < 40yo• Carotid or Vertebral Dissection• Underlying coagulopathy

– Protein S or C Def, Antithrombin III def, Factor V Leiden, Antiphospholipid syndrome

Less Likely •Congenital Heart Defect

– PFO, ASD, PDA• Prolonged immobility• Neoplastic Process• Collagen vascular disorders

– SLE, RA, Sjogrens, FMD, Myositis• Trauma

Menu of Tests For Pt Work-Up• Most Common

– CTA Neck w & w/out contrast – ECG– ECHO with agitated saline– MR Head w/o Contrast

• Less Common– Chest X-ray– Venous Duplex Lower Extremities

Bilaterally– CT Chest, Abdomen, Pelvis w/ contrast

Pt A: Opacity in R Lung Base

PACS, BIDMC

• ET tube tip is 3 cm about carina

• Lungs w/ minimal atelectasis at the L base

• Rounded opacity in R cardiophrenic angle– 3 cm in diameter

projecting mostly over R lung base

• Linear opacity proximal to R hilus

Pt A: AVM on Contrast CT

PACS, BIDMC

• Homogenously enhancing structure in R middle lobe adjacent to pericardial fat

• Large feeding vessel arising from pulmonary artery approaches lesion

• Findings consistent with large pulmonary arteriovenous malformation (AVM)

• AVM enhances homogenously w/out evidence of thrombus

Pt A: Pulmonary Arteriovenous Malformation (PAVM)

• Aberrant connection between pulmonary artery and venous circulation that bypasses capillary system

• High flow low resistance

• 50-70% of PAVMs are located in the lower lobes

Normal Anatomy vs PAVM

http://galileo.phys.virginia.edu/classes/304/heart3.gif

http://www.med.yale.edu/intmed/cardio/imaging/findings/pulmonary_angio_a/ graphics/rad1.gif

• Pulmonary angiogram demonstrated substantial aneurysmal dilation of interlobar branch of with finding consistent with a large AVM

Complications from PAVM

• Hemorrhage: Hemoptysis or Hemothorax

• Massive R to L shunting: Hypoxemia, Dyspnea, Clubbing, Cyanosis, Polycythemia

• Paradoxical Emboli: cerebral abscess, embolic stroke, TIA’s– Serious neurological complications occur in up to 35%

of pt w/ PAVM*

*Cottin V et al. Pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: a series of 126 patients. Medicine (Baltimore) 2007 Jan;86(1):1-17

Treatment• AVM > 3 mm require tx• Transcatheter Embolotherapy

(TCE) is treatment of choice– avoids major surgery and

general anesthesia – loss of lung parenchyma

• TCE Procedure: Coils are threaded through a catheter into the pulmonary artery and placed both distally in the draining vein and proximally in the feeding artery of the AVM

http://www.ispub.com/xml/journals/ijpm/vol5n2/pavm-fig4.jpg

Companion Patient #1

Treatment Complications• Most Common:

– Pleuritic chest pain – Paradoxic embolization– Air emboli– Recanalization

• Less Common– Infection– Pulmonary infarction– Pulmonary Hypertension– Deep venous thrombosis– Dislocation of coils– Bleeding http://www.ispub.com/xml/journals/ijpm/vol5n2/pavm-fig4.jpg

Companion Patient #1

Pt A: Treatment

• Substantial dilation of interlobar branch appreciated on angiogram

• Feeding artery unsuitable for secure placement of balloons or coils due to size and high flow

• 10mm Amplatz occluder device deployed • No filling or arterial phase opacification of the AV on

follow-up angiogram

PACS, BIDMC

DDx: Pulmonary AVM• Most Common:

– Hereditary Hemorragic Telangiectasia (HHT) (80%)• Less Common:

– Chronic Inflammatory Conditions– Hepatic Cirrhosis– Mitral Stenosis– Schistosomiasis– Actinomyces– Trauma– Fanconi’s Syndrome– Metastic Thyroid Carcinoma

Hereditary Hemorrhagic Telangiectasia• Autosomal Dominant:

– Incidence 1/10,000 – Varying penetrance– Mutations in genes encoding Endoglin or

ALK-1, both membrane receptors of TGF-ß

• Diagnostic Criteria:1. Spontaneous, recurrent epistaxis2. Multiple mucocutaneous telangiectasias3. Visceral involvement4. 1° relative with HHT

Amin H. Pulmonary Arteriovenous Malformations And Osler Weber Rendu Syndrome: An Unusual Cause Of Dyspnea. The Internet Journal of Pulmonary Medicine. Dec. 2007 ISSN: 1531-2984.

Clinicial Features of HHT• Recurrrent Epistaxis (95%)• Multiple mucocutaneous

telangiectasias (75%) – lips, hands, face

• GI bleeding (20-25%)• AVMs

– Pulmonary (30-50%)– Cerebral (5-20%)– Hepatic (up to 30%)*

• Fe deficiency anemia

Maher et al. Cerebrovascular Manifestations in 321 Cases of Hereditary Hemorrhagic Telangiectasia. Stroke. 2001;32: 877-882.

PAVMs: Summary• Morbidity and mortality

– embolic stroke, brain abscess, and intracranial hemorrhage

• HHT is the most common etiology for PAVM– Patients and 1º relatives should be screened

• Embolotherapy or surgery is required for:– Symptomatic patients– PAVM with feeding arteries > 3 mm in

diameter

References• Plauchu H; de Chadarevian JP; Bideau A; Robert JM . Age-related clinical profile of hereditary hemorrhagic

telangiectasia in an epidemiologically recruited population. Am J Med Genet 1989 Mar;32(3):291-7• Naess, H., Nyland, H. I., Thomassen, L., Aarseth, J. & Myhr, K.-M. Etiology of and risk factors for cerebral

infarction in young adults in western Norway: a population-based case-control study. European Journal of Neurology 11 (1), 25-30.

• Flinte et al. Mechanical Thrombectomy of Intracranial Internal Carotid Occlusion Pooled Results of the MERCI and Multi MERCI Part I Trials. Stoke. 38 (4): 1274. (2007)

• Amin H. Pulmonary Arteriovenous Malformations And Osler Weber Rendu Syndrome: An Unusual Cause Of Dyspnea. The Internet Journal of Pulmonary Medicine. Dec. 2007 ISSN: 1531-2984.

• Cottin V, Chinet T, Lavole A, Corre, Marchand E, Renyaud-Gaubert M, Plauchu H, Cordier JF. Pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: a series of 126 patients. Medicine (Baltimore) 2007 Jan;86(1):1-17

• Cottin V et al. Pulmonary Vascular Manifestations of Hereditary Hemorrhagic Telangiectasia (Rendu-Osler Disease)Respiration. 2007;74(4):361-78.

• Maher et al. Cerebrovascular Manifestations in 321 Cases of Hereditary Hemorrhagic Telangiectasia. Stroke. 2001;32: 877-882.

• Andersen PE, Kjeldsen A. Clinical and Radiological Long-Term Follow-up After Embolization of Pulmonary Arteriovenous Malformations. Cardiovasc Intervent Radiology. 2006 Jan-Feb;29(1):70-4

• Kjeldsen AD, Oxoj H, Andersen PE, Green A, Vase P. Prevalence of pulmonary arteriovenous malformations (PAVMs) and occurrence of neurological symptoms in patients with hereditary haemorrhagic telangiectasia (HHT). Journal of Internal Medicine [0954-6820] 2000 vol:248 iss:3 pg:255 -6

• Hong Shan Zhong. Ke Xu. Haibo Shao .Transcatheter Closure of Bilateral Multiple Huge Pulmonary Arteriovenous Malformations with Homemade Double-Umbrella Occluders.. Cardiovasc Interventional radiology. 2007 Dec 7

• Gamillscheg, A, Schuchlenz H, Stein JI, Beitzke .Interventional Occlusion of a Large Pulmonary Arteriovenous Malformation with an Amplatzer Septal Occluder . A Journal of Interventional Cardiology Volume 16 Issue 4 Page 335-339, August 2003

Acknowledgements

• Special thanks to:• Andrew Hines-Peralta, MD• Aarti Sekhar, MD• Prachi Dubey, MD• Gillian Lieberman, MD