Management of Vascular Disease

Weighing Natural History Against

Outcomes after Interventions

Scott Berceli, MD PhD

Associate Professor of Surgery

CarotidStenosis

Carotid Endarterectomy

100%

AorticAneurysm

Open AAARepair100%

LegIschemia

Lower ExtremityBypass100%

Disease:

Treatment:

Standard Vascular Surgical Practice(circa. 2000)

CarotidStenosis

Carotid Endarterectomy

60%+

Carotid Stenting40%

AorticAneurysm

Open AAARepair20%

+Endograft AAA

Repair80%

LegIschemia

Lower ExtremityBypass

80%+

SFA StentingTibial Angioplasty

20%

Disease:

Treatment:

Standard Vascular Surgical Practice(circa. 2007)

Abdominal Aortic Aneurysms

Incidence • Found in 2-5% of individuals > 65 year old • Accounts for 1.2% of deaths in > 65 age group• 13th leading cause of death in U.S.

Risk Factors • Hypertension• Smoking• Family History (20% first degree relatives) • Male sex (4:1 M:F ratio)• Advancing age (rare in patients < 50 y.o.)

Rupture Risk

1960’s to 1990’s

2%

5%

10%

20%

0%

5%

10%

15%

20%

3.0 4.0 5.0 6.0 7.0 8.0

Size (cm)

Year

ly ri

sk o

f AA

A ru

ptur

e

Adapted from Szilagyi, Ann Surg, 1966

2004

ADAMs TrialUK Small Aneurysm

Patients with 4.0 to 5.5 cm AAA randomized to repair or observation

• no difference in AAA related mortality• 5.0-5.5 cm rupture risk 2% per year

]

VA Large AneurysmLongitudinal study of high risk patients with > 6.0 AAA

• 5.5 - 5.9 cm 9.2% per year• 6.0 - 6.4 cm 10.5 % per year• 6.5 - 6.9 cm 19.1% per year• > 7.0 cm 32.5% per year

]Determined from abd films

and physical exam

0%

5%

10%

15%

20%

3.0 4.0 5.0 6.0 7.0 8.0

Size (cm)

Year

ly ri

sk o

f AAA

rupt

ure

Revised

Previous

Timing of elective AAA Repair

• Repair vs. continued observation offered for AAA 5.0-5.5 cm• Repair recommended for AAA 5.5 cm (good risk patients)

+Operative Mortality

(open and endovascular) 2-4%

=

Presentation of Patients with Ruptured AAA

Classic Triad• Abdominal or back pain• Pulsatile abdominal mass• Hypotension

• 95% of all patients with rupture have at least 1 of 3 signs

• < 50% of patient with rupture have all 3 signs

Treatment is immediate operative repair within minutes

Symptomatic AAA

• Acute presentation of back or abdominal pain in a patient with a AAA (4.0 cm or greater) without other identifiable etiology

• Often accompanied by a tender aneurysm on exam

• Hemodynamically stable, with no evidence of rupture on CT scan

• Natural history his poorly known, felt to represent impending rupture (hours to day to weeks?)

• Warrants emergent vascular surgery evaluation, usually leading to urgent operative repair within hours

Symptomatic AAA = Ruptured AAA

Methods of AAA Repair

• Open• Endovascular

Open operative repair

Endovascular repair

• Material Components– Graft: woven polyester– Stent: nitinol (nickel-titanium)

exoskeleton• Thermal shape memory

– Non-absorbable polyester sutures• >2000 hand-sewn suture/stent graft

Primary Bifurcated Module Delivery Catheter

Infrarenal Placement

Completed Primary Deployment

Contralateral Limb Delivery Catheter Access

Contralateral Limb Deployment

Completed Repair

Carotid Artery Stenosis

Pathophysiology

50% or less due to disease of the carotid bifurcation

Risk Factors

• TIA’s

• Hypertension

• Cigarette smoking

• Hyperlipidemia

• Age, male sex, race, heredity

• Diabetes

History of carotid endarterectomy in the U.S.

Design a clinical trial

NASCETDesign

3000 patients randomized to medical or surgical therapy and followed for a minimum of 5 years

50 selected centers (<6% peri op stroke/death rate), sxs within 3 months, <80 yo; specific angio criteria

NASCET

2 year estimate by life table of ipsilateral stroke 26% for medical, 9% for surgical (70-99%)

18 mo mortality risk reduction 58%, stroke risk reduction 71%

NASCET

2 yr Estimate of Ipsilateral Stroke

Failure Rate NNT

Stenosis Medical Surgical

70-99% 26.1% 12.9% 8

50-69% 22.2% 15.7% 15

<50% 18.7% 14.9% 26

ACAS

• 39 centers, 17 credentialed surgeons (<3% for asymptomatic)

• <80 yo

• 1662 patients with >60% stenosis by angio

ACAS

Operative and angio stroke morbidity/mortality 2.3% (1.2% angio)

Surgery No Surgery

Projected 5 yr 5.1% 11%

stroke event rate

Stroke risk reduction 55% (only 17% for females)

ACAS

• Stroke risk reduces from 2%/yr to 1%/yr, or 5% at 5 yrs

• One stroke prevented for every 20 CEAs done in asymptomatic patients