Gilbert G. Florentino, MD

Makati Medical Center

1. Present a case of

arteriovenous malformation

2. Discuss the definition,

pathophysiology of

arteriovenous malformation

3. Discuss treatment options for

AV malformation

OBJECTIVES

A.F.

38/Male

Filipino

Easy fatigability

Shortness of breath for 7 months

Consulted

GENERAL DATA

13 years old

Edema , left arm

Developed varicosities

Dx: Hemangioma

No treatment done

No cardiac symptoms

History of present illness

26 years old progressive development of tortuous varicosities on Left upper arm

-graft prosthesis Left

subclavian artery

-noted improvement

post surgery

25 years old –gradual enlargement,

Left arm

multiple tortuous varicosities

Dx: AV Malformation left upper arm

- repair of AV malformation and ligation of feeding arteries

History of Present Illness

32 years old new varicosities on medial left arm with progressive dilatation, with extension to the left upper chest and neck

7 months PTC

still with varicosities on L arm

- (+) easy fatigability

- (+) shortness of breath

Patient was advised surgery

Patient consulted

History of Present Illness

REVIEW OF SYSTEMSGENERAL: (-) anorexia,(-) fever,(-) weight loss,

generalized body weakness, numbness; (-) loss of consciousness (-) headache; (-) loss of appetite

SKIN: (-) rash, hematoma, jaundice, abnormal pigmentation, itching

HEENT: (-) tinnitus, hearing loss, dryness of the mouth, dysphagia, eye pain; (-) blurring of vision

CARDIOVASCULAR: (-) chest pain; (-) orthopnea and(-)palpitations; (-) easy fatigability

REVIEW OF SYSTEMSGASTROINTESTINAL: (-) epigastric pain; (-) melena,

diarrhea, nausea, vomiting, urinary and bowel incontinence

GENITOURINARY: (-) dysuria, oliguria, hematuria, nocturia

ENDOCRINE: (-) polyuria, polydipsia, polyphagia, heat/cold intolerance

MUSCULOSKELETAL: (-) joint pains, tremors, weakness of the extremities, stiffening of extremities, back pain,(-)

PAST MEDICAL HISTORYNon hypertensive, non diabetic, non asthmatic

(+) diagnosed with Congenital AV malformation, left upper arm (1987)

S/P Ligation of Feeders left arm (1999)

S/P Graft prosthesis on Left Subclavianartery (2000)

S/P Inguinal herniorrhaphy, left (2004)

FAMILY HISTORY(+) Gastric Cancer – father

(+) Leukemia –mother

UNREMARKABLE

SOCIAL HISTORY

PHYSICAL EXAMINATION• Conscious, coherent, ambulatory,

not in cardiorespiratory distress

• BP 130/80 HR82 regular RR20 T 36.7

• Anicteric, pink conjunctivae, moist buccal mucosa, no tonsillopharyngeal congestion, no nasoaural

discharge,no CLAD; (+) multiple tortuous varicosities on the left neck extending to the left upper chest wall and left upper arm, (+) warm to touch, non-erythematous, non tender (+) thrill, (+)bruit

PHYSICAL EXAMINATION• Equal chest expansion, clear lungs

• Adynamic precordium, AB at the 6th LICS MCL, regular rhythm, no S3 or S4, (+) grade 3/6 systolic murmur at the LPSB, 4th ICS; (+)thrill on tortuous veins on the anterior chest wall, neck and left arm

• flat, soft, normoactive bowel sounds, non tender, no masses, no tenderness

• full equal pulses, no cyanosis, no edema

• Peripheral Arterial Disease

• Congenital Arteriovenous Malformation, Left upper arm, Left Anterior Chest and Neck

• Functional Class II-A

• S/P Ligation of Feeders left arm (1999)

• S/P Graft prosthesis on Left Subclavian artery (2000

• S/P Inguinal herniorrhaphy, left (2004)

IMPRESSION

CBC 3/9/12

Hgb 12.9

Hct 39.2

WBC 3.75

Seg 40

Lym 48

Mono 8

Eo 4

Plt 197,000

CBC (3/9/12)

3/9/12

Na 141

K 4.2

Creatinine 0.76

SERUM ELECTROLYTES (3/9/12)

PTT

Patient 29.7

Control 25.8

PT

Patient 12.3

Activity 84.6

Control 11.5

INR 1.07

COAGULATION PARAMETERS

SMALL OVOID DENSITY IN THE LEFT UPPER LOBE (could be due to a calcific granuloma or merely a blood vessel viewed en face).

Otherwise, normal.

CHEST X-RAY (3/9/12)

ECG (3/9/12)

CHEST CT ANGIOGRAPHY (Nov. 2011)

Normal CT examination of the lungs

Right atrial enlargement due to increased flow from AVM of the Left upper extremity.

Left ventricular enlargement.

No pericardial or pleural effusion.

No evident mediastinal, hilar or axillary lymphadenopathy.

Normal CT angiography of the thoracic aorta and pulmonary vessels.

No evident thoracic aortic aneurysm, wall dissection or pulmonary embolism.

CHEST CT ANGIOGRAPHY(Nov. 2011)

High flow arteriovenous fistula, arterial feeders immediately proximal and distal to the graft prosthesis, arising from the left distal subclavian/left proximal axillary and left distal axillary artery

Large draining venous channels presumably representing ectatic cephalic, brachial and axillary veins.

Non visualization of the left subclavian vein.

Venous extension with arterial blood into the anterior sternal area and left side of the neck.

CT ANGIOGRAPHY OF LEFT UPPER EXTREMITY

Dilated LV with normal wall motion and contractility

Normal LV Ejection Fraction 64% (Teicholz)

Dilated LA, w/o thrombus

RAE, RVE

Normal main pulmonary artery, aortic root and proximal ascending aorta

Normal MV, AV, TV, PV

No pericardial effusion

2DECHO (3/14/12)

Color Flow and Doppler Study:

Mild Mitral Regurgitation

Moderate Tricuspid Regurgitation

Normal pulmonary artery pressure 185msec by PAT

- Belong to Vascular Malformations

- Defects of the circulatory system that arise during embryonic or fetaldevelopment or soon after birth

- Masses of abnormal blood vessels

- Consist of a blood vessel “NIDUS” (NEST)

Through w/c arteries = veins

DEFINITION

- Mass covered by normal

color or angiomatous skin

- Smooth and shiny

- Increased local

temperature

- (+)fremitus and murmur

- tortuous

- Drainage veins

• MAIN LOCATIONS

o Head and neck 40%

o Extremities 40%

o Trunk 20%

CLINICAL CHARACTERISTICS

• Arise during early fetal development due to failure of regression of AV channels in the primitive retiform plexus

• Most occur sporadically

• ULTRASONOGRAPHY

Method of choice for initial evaluation

Demonstrates anechoic tubular structures w/o well-defined soft tissue masses

Doppler:

o Areas of arteriovenous shunt

o Increased peak systolic velocity

o Ectatic veins with arterialized flow

• MRI Areas with signal absence (flow void) on T1 and T2-

weighted sequences No mass adjacent to pathological vessels

• CT Multiple ectatic supplying arteries Early contrast-enhancement of the drainage veins

with no significant interposed mass

• ARTERIOGRAPHY Gold standard for AVM diagnosis Early contrast enhancement of venous structures (+) malformative nidus

• vascular malformations are responsive to stimuli (ex.injury and surgery), improper treatment rapidly stimulates quiescent vascular malformations –worsens the condition.

• Feoktistov et al

Hypoxia modulates the expression of adenosine receptors in human endothelial and smooth muscle cells toward an angiogenic phenotype

PRINCIPLES OF TREATMENT

• Only potential cure: COMPLETE DESTRUCTION OF THE NIDUS OF A VASCULAR MALFORMATION

• Ameliorating clinical symptoms is another goal for problematic vascular malformations

PRINCIPLES OF TREATMENT

• Surgical resection

• Laser therapy

• Direct puncture sclerotherapy

• Arterial embolization

PERIPHERAL VASCULAR MALFORMATION: TREATMENT

• Absolute indications for treatment:

• Progressive pain or discomfort

• Functional alterations impairing daily activities or quality life

• Severe deformity

• Vascular bone syndrome

• Hemorrhage

• High output heart failure

• Complications secondary to venous hypertension

• Life threatening lesions

PERIPHERAL VASCULAR MALFORMATION: TREATMENT

Percutaneous puncture of the lesion with a fineneedle attached to a small extension tube

Promotes:

• blood coagulation

• protein denaturation

• severe inflammatory process obliterationof the malformed cavities

Performed under fluoroscopic guidance

SCLEROTHERAPY

ABSOLUTE ETHANOL

Used for the treatment of surgicallyinaccesible lesions

ETHANOLAMINE OLEATE

Less effect on the deep vascular layer

Not associated with neurologic side effects

POLIDOCANOL

Used for sclerotherapy of esophageal and lower limb varices

SCLEROTHERAPY

BLEOMYCIN OK – 432 (Picibanil)

Prepared with Streptococcus pyogenes cells with benzylpenicillin

Utilized for the treatment of lymphatic malformations (macrocystic)

Direct puncture

Low complication rates

Used more frequently for lymphatic malformations

Diluted at a concentration of 1 mg/ml

Most common complications:• Cellulitus• Ulcerations• Hair loss• Cold – like symptoms

SCLEROTHERAPY

Transarterial or transvenous

Preferred treatment of high flow marformation

Solid embolizing agent: platinum metal coils with controlled detachment

Accessed by means of remote arterial puncture with application of liquid and solid particles

EMBOLIZATION

N – BUTYL- CYANOACRYLATE (NBCA) Ethylene vinyl alcohol copolymer (Onyx)

-Acts by precipitation occluding the vessel

-Radiopaque

-Non adhesive

-Long procedure time

-Treat high and low-flow malformations

-Lower rates of complications

-Utilized for treatment of high – flow vascular malformation ( Arterial Malformation)

-Acts by polymerizing when in contact with blood

EMBOLIZATION

Monitoring of the distal blood flow and nervesensation

CT scan, MRI and Color Doppler UTZ: done after 3days of sclerotherapy to evaluate the efficacy oftherapy

At least 2 years of follow up is recommended

FOLLOW UP

• Angiography and Embolization considered

• Purpose of Embolization:

Control growth of AVMs and bleeding

Use sufficient liquid embolizing agents to eradicate the nidus

Successful embolization:

Active bleeding stopped

Localized pulsation disappeared

Lesion lighter

Expanded veins in the neck return to normal

• Surgery indicated: Embolization fails or endovascular access of nidus is not possible

• Surgery difficult:

Vascularity

Lack of distinct margins

Involvement of major structures

• Commonly recur post-surgery

• GOAL OF SURGERY: resect entire nidus

• Lasers less effective with AVMs, rarely used

• Only cure: RADICAL RESECTION, possible only after a PREOPERATIVE ANGIOEMBOLIZATION

• If unresectable: ANGIOGENESIS-INHIBITING AGENTS

• Flow pattern of lesion

• Location (deep vs superficial)

• Operator experience

• Presence of adjunct surgery plan

• Cost

• availability

Main Factors that influence agent selection:

Superficial Low-flow PVM:

Ethanol sclerotherapy

NBCA embolization

Deep High-flow PVM:

NBCA and/or Onyx

Patients with planned adjunct surgery:

NBCA embolization

VEGF LEVELS IN CONGENITAL AVM?

UNKNOWN

ANGIOGENESIS-INHIBITING AGENTS

• Shunting and hypoxemia

• Aneurysm/rupture/bleeding/ hemorrhage

• Pulmonary Embolism

• Skin ulceration

• Cellulitis

• Gangrene

• Hyperpigmentation

• High cardiac output

• Lack of tissue perfusion

• Disfigurement

CLINICAL CONSEQUENCES OF AVM

AVM - SummaryAVMs are complicated vascular malformations which can grow in the brain, head and neck area, limbs, or even in organs.

An understanding of the functional vascular anatomy is critical to successful treatment.

Successful treatment requires a multi-disciplinary team that has constant interaction.

The combination of pre-surgery embolization followed by surgical resection is currently yielding the most successful results for head, neck and body lesions.