The SOS (Stenting Of Saphenous vein grafts)
Randomized, Controlled Trial of a Paclitaxel-Eluting Stent Vs. a
Similar Bare Metal Stent in Saphenous Vein Graft Lesions
Emmanouil S. Brilakis, MD, PhDDirector, Cardiac Catheterization Laboratory
VA North Texas Healthcare SystemOn behalf of the SOS investigators
I, Emmanouil Brilakis DO NOT have a financial interest/arrangement or affiliation with one or more organizations that could be perceived as a real or apparent conflict of interest in the context of the subject of this presentation.
Disclosure Statement of Financial InterestDisclosure Statement of Financial Interest
• Veteran Affairs, VISN-17• Clark R. Gregg fund, Harris Methodist
Foundation, Fort Worth, Texas
Funding
SOS design
• DESIGN: Prospective, randomized, multi-center trial comparing the Taxus™ paclitaxel-eluting stent (PES) with a similar Express2™ bare metal stent (BMS) in saphenous vein graft (SVG) lesions
• OBJECTIVE: To compare the 12-month angiographic and 24-month clinical outcomes between PES and BMS in SVG lesions
• PRINCIPAL INVESTIGATOR: Emmanouil S. Brilakis, MD, PhD. VA North Texas Healthcare System, Dallas, Texas
SOS: sample size determination
• 31 patients needed per group to have 80% power (2-sided alpha 0.05) to detect a 66% reduction in binary angiographic restenosis assuming 50% restenosis in BMS group and 1 lesion treated per pt
• Target enrollment: 40 patients per group to account for losses during follow-up
SOS: Patient flow80 patients (112 lesions) enrolled between
2005 and 2007 in 5 clinical sites in USA and Europe
Died: 1 ptDeclined: 5 pts
Angiographic follow-up at 12 months
33 pts47 lesions
Clinical follow-up at 24 months
Clinical follow-up at 24 months
Angiographic follow-up at 12 months
33 pts43 lesions
BMS39 pts
55 lesions
PES41 pts
57 lesions
Died: 4 ptsEmergent CABG: 1 ptDeclined: 3 pts
Died: 1 pt Died: 1 pt
median follow-up: 18 months
Iowa City VAMC•James Rossen, MD
Michael E. DeBakey VAMC•Biswajit Kar, MD
VA North Texas HCSCoordinating Ctr•Emmanouil Brilakis, MD, PhD•Subhash Banerjee, MD •Christopher Lichtenwalter, MD•James de Lemos, MD•Owen Obel, MD•Michele Roesle, RN
Little Rock VAMC•Joe K. Bissett, MD•Rajesh Sachdeva, MD
SOS trial centers
Collaborators:Peter Berger, MDPanayotis Fasseas, MD
Onassis Cardiac Surgery CtrAthens, Greece•Vassilios Voudris, MD•Panagiotis Karyofillis, MD
BMS n = 39
PES n = 41
P Value
Age (yrs) 67± 9 66 ± 9 0.71Men (%) 100 100 1.0White (%) 90 98 0.19Diabetes (%) 44 44 0.98Current smoker (%) 23 29 0.53Hypertension (%) 95 93 0.69Hyperlipidemia (%) 95 98 0.53
Baseline characteristics I
BMS n = 39
PES n = 41
P Value
Years since CABG 12 ± 6 11 ± 6 0.84Presentation 0.53 - Stable angina (%) 33 29 - ACS (%) 57 63BMI (kg/m2) 29 ± 4 30 ± 5 0.32Prior MI (%) 59 56 0.79Normal ejection fraction (%) 61 51 0.53
Baseline characteristics II
BMS n = 39
PES n = 41
P Value
SVG recipient vessel 0.37 - LAD/diagonal (%) 30 27 - Circumflex/OM (%) 30 44 - RCA/PDA (%) 40 29Lesion location 0.80 - Aortic anastomosis (%) 27 26 - Body (%) 66 67 - Distal anastomosis (%) 7 7
Procedural description I
BMS n = 39
PES n = 41
P Value
Number of SVGs treated 1.15 ± 0.37 1.12 ± 0.33 0.68Number of lesions treated 1.41 ± 0.64 1.39 ± 0.70 0.89Number of stents/lesion 1.13 ± 0.34 1.09 ± 0.29 0.50Predilatation (%) 29 33 0.63Embolic protection (%) 56 51 0.56Max balloon diameter, mm 3.20 ± 0.48 3.30 ± 0.52 0.40Max inflation pressure, atm 17 ± 3 17 ± 3 0.37Stent length, mm 18 ± 6 18 ± 6 0.90
Procedural description II
BMS n = 39
PES n = 41
P Value
Heparin (%) 79 83 0.69GP IIb/IIIa inhibitors (%) 13 10 0.66Contrast, mL 257 ± 105 262 ± 98 0.84Fluoroscopy, min 20 ± 9 21 ± 11 0.64
Post PCI MI (%) 7 6 0.87Procedural success (%) 97 95 0.59
Procedural description III
Late Loss
mm
± 1.03
BMS (47 lesions), PES (43 lesions)
Diff (95% CI)-0.87 (-0.51, -1.22)P<0.0001
Diff (95% CI)-0.81 (-0.48, -1.46)P<0.0001
± 0.57
± 0.98
± 0.54
Binary angiographic restenosis
%
Primary study endpoint
relative risk: 0.1895% CI: 0.07, 0.48
p < 0.0001
0
25
50
75
100
0 1 2 3 4Minimum lumen diameter (mm)
%
BMSPES
Before intervention
Cumulative frequency distribution curves
0
25
50
75
100
0 1 2 3 4Minimum lumen diameter (mm)
%
BMSPES
Before intervention
After interventionAfter intervention(in-stent minimum lumen diameter)
Cumulative frequency distribution curves
0
25
50
75
100
0 1 2 3 4
BMSPES
%After intervention
Follow-upBMS
In-stent minimum lumen diameter (mm)
Follow-upPES
Cumulative frequency distribution curves
BMS n = 39
PES n = 41
P Value
Death (%) 5 12 0.27Myocardial infarction (%) 31 15 0.10TLR (%) 28 5 0.003TVR (%) 31 15 0.08Any revascularization (%) 41 20 0.02Target vessel failure (%) 46 22 0.03Overall MACE (%) 49 37 0.20ARC definite/probable stent thrombosis (%) 13 2 0.07
Clinical outcomesmedian follow-up: 1.5 years
0
10
20
30
40
50
60
0 1 2
Hazard ratio, 1.56 P=0.27
No. at riskBMSPES
3941
3740
3134
2219
1212
0.5 1.5
Years from stenting
Death from any cause%
of P
atie
nts
COPDMI
Lung CASBO
StrokeMI unknown
BMS
PES
No. at riskBMSPES
3941
3039
2330
1515
108
Myocardial infarction
0
10
20
30
40
50
60
% o
f Pat
ient
s
Years from stenting
PES
BMS
Hazard ratio, 0.67 P=0.10
0 1 20.5 1.5
0
10
20
30
40
50
60
Hazard ratio, 0.38 P=0.003
0 1 2
No. at riskBMSPES
3941
3340
2332
1317
810
0.5 1.5Years from stenting
Target lesion revascularization%
of P
atie
nts
PES
BMS
No. at riskNo. at riskBMSBMSPESPES
39394141
28283838
19192727
11111313
6677
Target vessel failureCardiac death, MI, TVR
Years from stenting
00
1010
2020
3030
4040
5050
6060
% o
f Pat
ient
s
00 11 220.50.5 1.51.5
Hazard ratio, 0.65 P=0.03
BMS
PES
5850
9882
6889
7464
0
20
40
60
80
100
6 months 12 months 18 months 24 monthsPES BMS
Clopidogrel use
P=NS
% o
f Pat
ient
s
In saphenous vein graft lesions, compared to a similar bare metal stent, the Taxus™ PES resulted in:
• Significant reduction in 12-month binary angiographic restenosis, target lesion revascularization and target vessel failure• Trends for lower target vessel
revascularization, myocardial infarction• No difference in mortality and stent
thrombosis
Conclusions