1. The Performance of The Aorfix Endograft in
Severely Angulated Proximal Necks in the
PYTHAGORAS U.S. Clinical Trial
Mahmoud Malas, MD, MHS
Director Of The Center For Surgical Trial and Outcome Research
Johns Hopkins Hospital
Chief Of Endovascular Surgery
Johns Hopkins Bayview Medical Center
SOUTHERN ASSOCIATION FOR VASCULAR SURGERY
39th Annual Meeting

2. Disclosures
Disclosure
Speaker name: Mahmoud Malas
.................................................................................
Principle Investigator:
1. PYTHAGORAS: AORFIX (Lombard Medical)
2. PRICELESS: EndoSure (CardioMEMS)
3. ENDOREFIX: Endorefix (Lombard Medical)
4. Anchor: HeliFX (Aptus Endosystems)
5. Relay: (Bolton Medical)

3. Acknowledgement
For the Pythagoras Investigators
William D Jordan, MD, University of Alabama, Birmingham, AL
Michol A Cooper, MD, PhD, Johns Hopkins, Baltimore, MD
Umair Qazi, MD, Johns Hopkins, Baltimore, MD
Adam W Beck, MD3, University of Florida, Gainesville, FL
Michael Belkin, MD4, Brigham and Women’s Hospital, Boston,
MA
William Robinson, MD UMass , Worcester. MA
Mark Fillinger, MD, Dartmouth-Hitchcock Medical Center,
Lebanon, NH

4. Aorfix™ Device
 Designed and tested to
treat highly angulated
aortic necks
 Highly flexible, soft,
conformable device
 Polyester fabric, Nitinol
rings

5. Aorfix™ Device
4 pairs of hooks
proximally
Can be deployed trans-
renal

6. Dimensions of Aorfix™ Seal Zone
0mm
8mm
15mm
Radial force in
the proximal 8mm
is 4 times greater
than in the next
7mm because
stent rings are
more closely
spaced

7. U.S. Pythagoras Clinical Trial
 EVAR Arms:
 ‘Roll-in’ Group: 67 EVAR pts (standard neck angle
<60°)
 Primary Study Group: 151 EVAR pts (neck angles
>60°): 109 pts highly-angled (60°-90°)
42 pts severely angled >90°

11. U.S. Pythagoras Clinical Trial
 Control Arms:
 SVS Registry meta-analysis of
control patients from US EVAR
clinical trials (n=323)
 Concurrently enrolled Open
Surgical controls (n=76)

12. Demographics
 Age: EVAR 76 ± 7, vs. open 69 ± 7 years
(p<0.001)
 Female: EVAR 29%, high angle 35%, open 20%
(p<0.02)
 Similar AAA sac diameter (5.8 cm in each group,
p=ns)

13. Hostile Neck
20% rate of aneurysm expansion
30% rate of device migration
24% rate of type I endoleak
Fourfold increased risk of type I
endoleak at 1 year (meta-analysis).
Lovegrove et al., 2008,; Aburahma et al., 2011; Sternbergh
et al., 2002; Torsello et al., 2011; Abbruzzese et al., 2008,
Antoniou et al., 2013,

14. Objectives
To evaluate the performance of Aorfix
in highly and severely angled aortic
neck

15. Absence of proximal neck
dilatation and graft migration
following endovascular aneurysm
repair with balloon expandable
stent-based endograft.
J Vasc Surg October 2005; 42: 639-644

16. Recoil Force
Radial Force
Radial Force > Recoil Force PND
Over size approximately 20%

17. Objectives
To evaluate the performance of Aorfix in highly and
severely angled aortic neck
To evaluate the long term morphological changes in
aneurysm neck following EVAR
To evaluate the impact of neck diameter changes on
graft related complications

18. Anatomy
Mean
± SD
Aorfix
<60°
N=67
Aorfix
60 - 90°
N=109
Aorfix
>90°
N=42
COS
ITT
N=76
Sac Diameter (mm) 54 ± 9.0▲ 59 ± 11.7 58 ± 12.6 58 ± 8.8
Sac Volume (cc) 168 ± 68.4▲ 215 ± 103.7 227 ± 119.9 201 ± 88.7
Neck Dia (mm)
1mm Infrarenal
23± 3.4 22± 2.7▲ 22± 2.7▲ 25 ± 5.2
Neck Dia (mm)
7mm Infrarenal
23 ± 3.1▲ 23 ± 3.2▲ 22 ± 3.0▲ 28 ± 6.8
Neck Dia (mm)
15mm Infrarenal
25 ± 4.3▲ 24 ± 4.9▲ 25 ± 7.2▲ 33 ± 8.8
Proximal Neck Length
(mm)
24 ± 15.4▲ 23 ± 11.5▲ 19 ± 14.9▲ 13 ± 12.7
Proximal Neck Angle (°) 45 ± 12.3 76 ± 8.1▲ 101 ± 11.9▲ 48 ± 23.3

19. Major Adverse Events and
Mortality
Aorfix™
<60°
N=67
Aorfix™
60-90°
N=109
Aorfix™
> 90°
N=42
COS
Group
N = 76
p-value: Aorfix vs
COS control
Freedom from
SVS MAE (30 d) (%)
92.5 83.5 76.2 57.9
<60: 0.001
60 - 90: 0.001
> 90: 0.04
Mortality (30 d) (%) 1.5 0.9 4.8 1.3
<60: 0.9
60 - 90: 0.80
> 90: 0.26
Mortality (1 yr) (%) 3.0 7.3 9.5 6.6
<60: 0.32
60 - 90: 0.97
> 90: 0.56
Mortality (2 yr) (%) 4.5 13.8 14.3 10.5
<60: 0.32
60 - 90: 0.51
> 90: 0.55

20. Effectiveness at 1 and 2
years
Aorfix
< 60°
Aorfix
60 - 90°
Aorfix
> 90°
p-value:
Aorfix 60° – 90°
and
Aorfix > 90°
vs. Aorfix <60°
Sac shrinkage (>5 mm)
1 year (%)
39.2 43.0 42.9
60 – 90: 0.72
> 90: 0.81
2 years (%)
55.1 54.7 48
60 – 90: 1.00
> 90: 0.63
Sac expansion (>5 mm)
1 year (%)
0 1.2 3.6
60 – 90: 1.00
> 90: 0.35
2 years (%)
4.1 5.3 8
60 – 90: 1.00
> 90: 0.60
Type I/III leak
1 year (%)
0 1.3 3.7
60 – 90: 1.00
> 90: 0.37
2 years (%)
0 1.2 3.7
60 – 90: 1.00
> 90: 1.00
Migration (>10 mm)
1 year (%)
0 1.2 3.6
60 – 90: 1.00
> 90:0.35
2 years (%)
2.0 1.2 3.6
60 – 90: 1.00
> 90:1.00

21. Freedom from Migration at 5 Years

22. Neck Measurement Pre-Determined Points
SMA
1mm below SMA
5mm above proximal Renal
1mm below distal Renal
7mm below distal Renal
15mm below distal Renal

23. Relative Risk of Complications
subsequent to Aortic Diameter Increases
in first 5 years
≥ 10% diameter
change at:
Barb
Fracture
N=471
Migration
>10mm
N=543
Sac
Shrinkage
N=511
Sac
Expansio
n
N=511
Type 1 & 3
Endoleak
s
N=456
1mm below
SMA
5mm Above P
renal
RR 4.39
p 0.010
RR 2.64
P 0.078
1mm below D
Renal
RR 1.49
p 0.081
RR 4.34
p 0.002
RR 2.17
p 0.060
7mm below D
Renal
RR 0.21
p 0.166
RR1.17
P 0.090
15mm below D
Renal
[All annual observations over 5 years used: multiple data points for every patient
drives significance. Empty cells had no statistical significance]

24. Oversizing
Oversize % = (1 – aortic diameter measured at a
given time/stent graft diameter) x 100

25. Planned Oversizing vs
Change in Oversizing at 3 years: 1mm below
Distal Renal

26. Planned Oversizing vs
Change in Oversizing at 3 years: 15mm below
Distal Renal

27. Evaluation of changes in aortic diameter
from the SMA to lower end of the
infrarenal neck
-5
0
5
10
15
20
25
Index 30 Day 1 Year 2 Years 3 Years 4 Years 5 Years
%Oversize
Follow-Up Time Point
1mm below SMA 5mm above Proximal Renal
1mm below Distal Renal 7mm below Distal Renal
15mm below Distal Renal

28. Conclusions
PYTHAGORAS is the first clinical trial to
include patients with >60° angled neck
Freedom from MAE was better in standard,
highly and severely angled groups compared
to open
Postoperative, one and two year survival
rates were similar among all groups
compared to open

29. There is constant morphological
changes in aneurysm neck following
EVAR
The infra-renal aorta dilates more
rapidly than the suprarenal aorta
There is a trend over 5 years to
match the endograft size
Conclusions

30. Conclusions
Proximal neck dilatation >10% (1mm below
the distal renal) increase the risk of:
Migration
Sac expansion (trend)
Distal neck dilatation >10% (> 7mm below the
distal renal) did not significantly increase the
risk of complications

31. Conclusions
Suprarenal aorta neck dilatation was
associated with migration
There was an association between the
degree of endograft oversizing and
aortic neck dilation