• Hospital mortality rate on average is 20% higher in non-trial hospitals. • 60% of hospitals perform fewer than 17 CEA per year. • 88% of surgeons perform at or below median value of 21 CEA per year. • Stroke morbidity is 7.7% in hospitals performing CEA at numbers in the

lowest quartile vs 2.5% for the highest quartile (p< 0.03). • CEA results are clearly better in high volume institutions / surgeons.

0

50

100

150

200

1971 1976 1981 1986 NASCET 1996 2001

Carotid Endarterectomy 1971 to 1999(Rates per Thousand)

1971 -- 15,000 CEA performed in U.S.1974-1985 - CEA most common vascular operation

> 1 million worldwide.1986 and 1988 - Rand data - “substantially overused”1988-present - complex, randomized, multi-center controlled clinical efficacy trials

1954 -- First carotid reconstruction for stroke prevention

1955 -- First CEA using techniques similar to 1999.

1971 -- 15,000 CEA performed in U.S.

1974-1985 - CEA became firmly established as the most common peripheral vascular operation with over 1 million performed worldwide.

1986 and 1988 - Rand Corp data - CEA “substantially overused”

0

50

100

15019

71

1973

1975

1977

1979

1981

1983

1985

1987

1989

NA

SCET

1993

AC

AS

1997

Carotid Endarterectomy 1971 to 1998(Rates per Thousand)

Year

CEA Cases/Quarter/100,000State of Florida

1992-1996

0

5

10

15

20

25

CEA

Cas

es

ACAS Advisory

Florida CEA Procedures as Percent of 1992-Q1 Adjusted for Age

0

50

100

150

200

250

CEA

Cas

es

65-6970-7475-7980+

1988-present -- an unprecedented series of complex, randomized, multi-center controlled clinical efficacy trials have been initiated and completed.

• NASCET (1991, 1998)• ECST (1991, 1996)• VA Cooperative Studies Program (1991) • CASANOVA (1991)• VA Cooperative Study Group (1993) • ACAS (1995)• ACST (ongoing)

Trials for symptomatic and asymptomatic stenosis

05

1015202530

ECST

NAS

CET

VA S

X

CA

SAN

OVA

VA A

SX

ACAS

SURGERY

MEDICINE

%