martin schillinger - i-meet congress

SFA long term results

Martin Schillinger

Long Term Results

20 years… not available

10 years… Palmaz stentsWallstent stents

• after 4 years no significant advantage compared to PTA• TASC A lesions• no nitinol stents

Nitinol Stents

Wallstents

24211815129630

100

80

60

40

20

0Mo

Log Rank p=0.008

7

25

8

28

9

33

13

38

17

53

21

69

32

91

45

113

52

123

Cumulative

Patency

69% - Nitinolstents

34% - Wallstents

Radiology 2004

Balloon expa

nding stent

s and Wallsten

ts did not im

prove

outcomes at 1

, 2, 3, 4 year

s…

… do we really

care about l

ong term data

of these ste

nts?

Long Term Results



3 to 5 years… Nitinol stents – non RCTs

J Endovasc Ther 2005J Endovasc Ther 2005

0

20

40

60

80

100St

ent F

ract

ure

Rat

es p

er P

atie

nts

(%)

15/78 8/29 2/11319.2% 27.6% 1.8%

43 months (24)107mm (71)

32 months (16)139mm (88)

15 months (9)125mm (84)

mean follow-up (SD)mean length (SD)

Wallstent Smart DynalinkAbsolute

p<0.001p=0.057

p<0.001

J Endovasc Ther 2005

These and o

ther data co

me from non‐r

andomized tr

ials –

are these da

ta valid?

Long Term Results



3 to 5 years… Nitinol stents – non RCTs

1 to 2 years… Nitinol stents – RCTs

???

Valid „long

term“ data from RCTs

are available

only

up to 2 year

s

Evidence fromrandomised trials

Lesion length

4.5cm 6.5cm 8.4cm 12.0cm

FAST

RESILIEN

T

ASTRO

N

ABS

OLU

TE

>15.0cm

…

FAST TrialBaseline Characteristics

• n=244• PTA (n=121) vs. primary stenting (n=123)

• Rutherford stages 2 to 5• de‐novo lesions• mean lesion length 4.5 cm (range 1 to 10cm)

• 1/4 chronic total occlusions• Luminexx nitinol stent (Bard)

Krankenberg H et al. Circulation. 2007;116:285‐292

Lesion length

4.5cm


No significant differences for any patient / lesion subgroups.

ConclusionsFAST

• In patients with a mean lesion length around 4 cm, primary stenting using the Luminexx Nitinol Stent did not improve morphological or clinical outcome at 12 months follow‐up.

• Subgroup analysis did not show a significant benefit of the Luminexx Stent for any lesion or patient subgroup.


Katzen B et al. TCT. 2007

• n=206• PTA (n=72) vs. primary stenting (n=134)

• Rutherford stages 1 to 3• mean lesion length 6.5 cm (range <15cm)

• 1/5 chronic total occlusions• Life Stent (Edwards)

RESILIENT TrialBaseline characteristics

Lesion length

6.5cm



BUT: 40.2% patients in the PTA group underwent bail‐out

stenting and were included as PTA‐failures at day 0!

ConclusionsRESILIENT

• In patients with a mean lesion length around 6 cm, primary stenting using the Lifestent improved morphological and clinical outcome compared to PTA alone.

• BUT: It remains unclear, whether primary stenting was superior compared to provisional stenting (PTA plus bail‐out stenting) in these patients.


ASTRON TrialBaseline characteristics

• n=73• PTA plus optional stenting (n=39) vs. primary stenting (n=34)

• Rutherford stages 2 to 5• de‐novo and restenotic lesions• mean treated length 8.4 cm (range 3 to 25cm)

• 1/3 chronic total occlusions• Devices: Astron Stent (Biotronik)

Schillinger M et al.

Lesion length

8.4cm

ASTRON Trial – Restenosisrates until 12 months


0

20

40

60

80

100

7/37 1/34 20/36 7/32 18/36 6/33 22/36 11/32

18.9% 2.9% 55.6% 21.9% 50.0% 18.2% 61.1% 34.4%

P=0.033 P=0.005 P=0.006 P=0.028Bina

ry Resteno

sis (%

)

3 Months 6 Months 6 Months 12 MonthsDUS DUS CTA DUS

PTA plus optional stenting Primary stenting

ConclusionsASTRON

• In patients with a mean treated length around 8 cm, primary stenting using the Astron Nitinol Stent improved morphological and clinical outcome compared to PTA with optional stenting.


ABSOLUTE TrialBaseline Characteristics

Schillinger M et al. N Engl J Med. 2006;354:1879‐1888

• n=104• PTA plus optional stenting (n=53) vs. primary stenting (n=51)

• Rutherford stages 2 to 5• de‐novo and restenotic lesions• mean treated length 12.0 cm (range 3 to 33cm)

• 1/3 chronic total occlusions• Devices: Dynlink / Absolute Stents (Abbott Vascular)

Lesion length

12.0cm

0

20

40

60

80

100

Angiograp

hic resten

osis

at 6 m

onths (%

)

P=0.032

PTA +/‐ Stent Stent(primary)

Intention to treat

23/53 12/51

43.4% 23.5%

P=0.010

PTA only Stent(primary or secondary)

Per protocol(as treated)

18/36 17/68

50.0% 25.0%

ABSOLUTE Trial ‐ 6 month angiographic restenosis

Schillinger M et al. N Engl J Med. 2006;354:1879‐1888

ABSOLUTE Trial – Restenosisrates until 2 years

Schillinger M et al. N Engl J Med. 2006;354:1879-1888 Circulation. 2007;115:2745-2749

0 3 6 9 12 15 18 21 24Follow‐up time (months)

20

40

60

80

100

Cumulative freedo

m

from

resteno

sis (%

)

Log rank P=0.02

4652

39 (7)40 (12)

33 (13)28 (24)

33 (13)28 (24)

29 (17)19 (33)

27 (19)19 (33)

27 (19)17 (35)

27 (19)17 (35)

25 (21)16 (36)

StentPTA

45.7%

69.2%

1st year2nd year

ABSOLUTE Trial ‐ Pattern of Restenosis until 24 months

• Sustained benefit of nitinol stents @ 2‐year follow‐up• No ‘catch‐up’ phenomenon• Restenosis later than 12 months was rare

Schillinger M et al. N Engl J Med. 2006;354:1879‐1888 Circulation. 2007;115:2745‐2749

37.0%

53.8%

0 3 6 9 12 15 18 21 24

Follow‐up time (months)

20

40

60

80

100

Cumulative freedo

m from

target vessel R

evascularisation

(%)

Log rank P=0.12

4652

46 (0)51 (1)

41 (5)44 (8)

38 (8)38 (14)

33 (13)37 (15)

32 (14)27 (25)

31 (15)25 (27)

31 (15)24 (28)

29 (17)24 (28)

ABSOLUTE TrialClinically driven TVR

StentPTA

Schillinger M et al. N Engl J Med. 2006;354:1879-1888 Circulation. 2007;115:2745-2749

ABSOLUTE TrialWalking capacity


ABSOLUTE TrialHaemodynamic outcome


• Primary stenting with the ABSOLUTE nitinol stent improved primary patency rates and clinical outcomes until 24 months, when compared with balloon angioplasty with optional stenting in lesions with a mean treated length of 12 cm.

ABSOLUTE TrialConclusion

12 mo restenosis vs. lesion length:Data from randomised trials

Length of the lesion (cm)

Bina

ry resteno

sis @ 12 mon

ths (%

)

PTA

Stent

FAST

FAST

RESILIENT

ASTRON

ABSOLUTE

ABSOLUTE

ASTRON

RESILIENT


Bina

ry resteno

sis @ 12 mon

ths (%

)

PTA plus provisional stent

Stent

FAST

FAST

RESILIENT

ASTRON

ASTRONABSOLUTE

ABSOLUTE

RESILIENT

12 mo restenosis vs. lesion length:Data from randomised trials

… with long/complex lesionsFAST – RESILIENT – ASTRON – ABSOLUTE

… with restenosis after prior PTAeven Wallstents were better than repeat PTA

… when an optimal primary result is crucial (CLI)because ulcer healing rather than long‐term patency counts

Primary stenting in patients…

CLI, critical limb ischaemia

Biamino et al TCT 2004

Long Term Problems:Which stents should we use?

Factors that determine fracture rates:– Length of the lesion– Type of stent– Fracture rates beyond 12 months?

Fracture rates in the context: Data from randomised trials

SIROCCO I SIROCCO II ABSOLUTE FAST RESILIENT

6 months 19% 9% 1.5% – 2.2%

12 months 31% 11% 1.5% 12% 2.9%

Length 85 mm 82 mm 124 mm 45mm 65mm

How to treat instent restenosis?

Unresolved long term problems of SFA stenting

How to handle stent fractures?

Do current data support the use of primary nitinol stenting?

– Currently liberal ‘stenting on indication’

Which stents should we use?– Stents with approved low restenosis and low

fracture rates from randomised trials

Why should we stent the SFA?– Symptomatic SFA disease is usually long and

complex: the best results in this indication are obtained with stents

Treating the SFA in 2008:in the Absence of Long‐Term Data

The future of interventional therapy for superficial femoral artery disease

The Future…is not:

POBA obviously is not the ideal treatment for longsegment SFA disease.

baseline Post PTA 3 months 6 months

The Future…

Technically feasible, but even non‐randomizedstudies are not convincing…

…there are very good reasons why RCTare not initiated for these devices.

Freez it?

CryoplastyCut it?

Cutting balloonAtherectomy

Burn it?

Laser

The Future…is not:

0

20

40

60

80

100

Conventionalballoon

Cutting Balloon

32% 62%

6 Mon

ths an

giograph

icresten

osis (%

)p=0.048

Amighi et al. Radiology 2008

SFA de‐novo lesions

0%

20%

40%

60%

80%

100%

Bina

ry Resteno

sis Ra

te (>

50%)

17/68

PTA PCB

p=0.421 month

6/22 2/17

PTA PCB

16/22 11/17

PTA PCB

9/22 8/17

p=0.753 months

p=0.736 months

27% 12% 41% 47% 73% 65%

Dick P et al. Radiology 2008

SFA instent restenosis

The Future…

A purely mechanic

al concept (sten

t) hardly will

be sufficient to r

esolve the prob

lem of SFA disease!

Promising Concepts –for the near future

Drug coated balloons

Biodegradable Stents

Drug eluting Stents

Drug eluting balloons –THUNDER Trial

Tepe et al. N Engl J Med. 2008;358:689‐699

• n=154 randomized to three groups:

‐ Paclitaxel coated balloon (n=48)

‐ Standard balloon (n=54)

‐ Paclitaxel disolved in contrast medium (n=52)

• Endpoints:

‐ Late lumen loss by angiography at 6 months

‐ TLR until 24 months



• claudication or critical limb ischemia (mean ABI 0.5)

• mean age 68 years

• 49% diabetics

• 27% chronic total occlusions

• 36% restenotic lesions

• mean leasion length 7.4cm



0

0.5

1

1.5

2

2.5

3

3.5

4

StandardBalloon

PaclitaxelBalloon

Contrast Mediaplus Paclitaxel

Angiograp

hic late lumen

loss @

6mo p<0.001

P=0.11



0102030405060708090

100

StandardBalloon

PaclitaxelBalloon


Bina

ry Resteno

sis @ 6 m

o (%

)

44%55%

17%



0102030405060708090

100

StandardBalloon

PaclitaxelBalloon


Target lesion

revascularisation

(%)

37% 52%

4% 15%

29% 40%

6 months

24 months

Restenosis vs. lesion length:Data from randomised trials


Bina

ry resteno

sis @ 12 mon

ths (%

)

PTA

Stent

FAST

FAST

RESILIENT

ASTRON

ABSOLUTE

ABSOLUTE

ASTRON

RESILIENT

THUNDER (6 Months)

Drug eluting balloons

Drug eluting balloon technology may improve restenosis

rates in short‐ to medium‐length SFA lesions.

However, the problems of residual stenosis and

elastic recoil remain unresolved.

Drug‐eluting Stents

30 days after coronary stenting (pigs)

Bare metal stent DES (Sirolimus)

Duda et al. Circulation 2002

Baseline Post Stent 6 Months

Drug‐eluting Stents

Restenosis at 2 years:DES 22.9%BMS 21.1%

Duda et. al JEVT 2006

0

10

20

30

40

6 Months 9 Months 18 Months 24 Months

SIROCCO I + II –Follow‐up until 2 Years

Drug‐eluting Stents –critical issues

• choice of drug: ‐limus family vs. paclitaxel

• duration of drug‐delivery

• polymeric vs. non‐polymeric stent platform

• dosage of delivered drug

• carrier platform (stent fractures!)

Drug‐eluting Stents –ongoing trials

Zilver‐PTX

• paclitaxel

• fast delivery

• non‐polymeric stent platform

• nitinol

STRIDES

• everolimus

• slow release kinetics

• polymeric stent platform

• nitinol

After the drug i

s released, DES

remains a purely m

echanical

concept, will thi

s be sufficient t

o resolve the

problem of SFA d

isease in the lon

g‐term?

Biodegradable Stents –critical issues

• choice of material: Mg‐alloy vs. polymeric materials

• problematic mechanical properties:‐ limited radial strength‐ limited flexibility‐ investigational products are all balloon expanding

• duration until stent desintegration / complete degradation

• vessel wall reaction to degradation process

• with vs. without drug coating

• coronary and BTK data are disappointing

The Future of SFA Treatment

1. next generation bare Nitinol stents– minimized fracture rates– optimized radial strength– short term restenosis < 1 year will remain the problem

2. Drug eluting Nitinol stents– based on latest generation nitinol BMS– postpone restenosis to > 1 year

3. Biodegradable (drug eluting) stents– resolve mechanical problems?– resolve restenosis?

4. Pro‐healing technologies??

martin schillinger - i-meet congress

Documents