A Clinical Study of the Safety and Efficacy of the Relay Thoracic Stent-Graft in Patients With Thoracic Aortic Pathologies

The purpose of this clinical trial is to assess and evaluate the safety and efficacy of the
Relay Thoracic Stent-Graft in subjects with TAA compared to surgical repair subjects.

This is a phase II multi-center, non-blinded, non-randomized study of treatment of the Relay
Thoracic Stent-Graft in subjects with thoracic aortic aneurysms.

The study will include 120 subjects treated with the Relay Thoracic Stent-Graft and 60
surgical controls enrolled at a maximum of 30 investigational sites. Pre-procedure baseline
data will be gathered along with post-procedure assessments prior to hospital discharge and
1, 6, and 1-year post-implantation follow-ups in addition to an annual visit out to 5 years.

Study Objectives

There are two primary objectives: efficacy and safety.

- Primary Efficacy will be evaluated by the device-related adverse event rate of
endovascular repair (via Relay Thoracic Stent-Graft) through 1- year.

- Primary Safety will be evaluated by comparing major adverse events through 1-year in
subjects treated with the Relay Thoracic Stent-Graft to those who underwent open
surgical repair.

Secondary objectives include evaluation of the primary outcomes including endoleak (Type I,
III and IV only), stent migration, lumen occlusion, deployment failure/conversion to
surgery, and aneurysm rupture at time points other than 1-year; evaluation of individual
outcomes of the composite safety endpoints (e.g., stroke, paraplegia, myocardial infarction,
respiratory failure, renal failure, and aneurysm-related mortality) at time points other
than 1-year; comparison of the clinical utilities (duration of procedure, procedural blood
loss, length of ICU and hospital stay, time in ICU) of the endovascular and surgical repair
groups; device integrity failures, vascular access difficulties and analysis of the change
in lesion size at 6-months, 1 year, and 2 -5 years post-procedure as compared to 1-month.

It is planned to enroll 120 subjects with diagnosed TAA into the endovascular cohort. Sixty
(60) surgical controls will also be included. For purposes of this study protocol, surgical
controls, or surgical subjects, are those treated by open surgical repair. The study will
be conducted at a maximum of 30 investigational sites in order to enroll the patient
population needed for analysis. Subjects will be enrolled on a first come / first serve
basis; however, a single investigational site may not enroll more than 30% of the enrollment
total.

Inclusion Criteria:

1. Subjects must be ≥ 18 years of age

2. The subject must meet at least one of the following :

1. Descending thoracic fusiform aneurysm, 5 cm in diameter or greater

2. Descending thoracic aneurysm that is 4 cm or more in diameter that has increased
in size by 0.5cm in last 6 months

3. Descending thoracic aneurysm with a maximum diameter that exceeds two times the
diameter of the non-aneurysmal, adjacent aorta

4. Saccular aneurysm in the descending thoracic aorta or Penetrating
Atherosclerotic Ulcers (PAUs)

3. Subject must have proximal and distal aortic neck suitable for stent- graft
placement, with diameter ranging between 18 mm and 42 mm.

4. Subject must have a proximal attachment zone distal to the left common carotid and a
distal attachment zone proximal to the origin of the celiac artery. The length of
the attachment zones will depend on the intended stent graft diameter. The proximal
attachment zone should be 15 mm for 22 - 28 mm grafts, 20 mm for 30 - 38 mm grafts,
and 25 mm for 40 - 46 mm grafts. The distal attachment zone should be 25 mm for 22 -
38 mm grafts and 30 mm for 40 - 46 mm grafts. Note that coverage of the left
subclavian artery is permitted. Additionally, coverage of the celiac artery is
permitted but only if this artery is already occluded at the time of the procedure.

5. Subject's vascular dimensions (e.g., aortic diameters, length from left subclavian to
celiac artery) must be in the range that can be safely treated with the Relay
Delivery Systems.

6. Subject has adequate vascular access (e.g., patent iliac or femoral arteries) for
introduction of the delivery system (26 Fr maximum outer diameter [8.7mm]).
Alternatively, subject may have femoral or iliac arteries that can be extended via an
access conduit.

7. Subject agrees to comply with 1 month, 6 months, and 1-year follow-ups, in addition
to an annual visit out to 5 years.

8. Subject (or Legally Authorized Representative, LAR) agrees to sign an Informed
Consent Form prior to treatment.

Exclusion Criteria:

1. Subject has any of the following conditions in his/her descending thoracic aorta:

1. Dissections - acute or chronic, in ascending or descending aorta

2. Intramural Hematoma (current or previous)

3. Acute Transection or Acute Traumatic Injury

4. Pseudoaneurysm (false aneurysm)

5. Symptomatic Aneurysm, including ruptured lesions

2. Subject's proximal neck diameter, measured outer-wall to outer-wall on a sectional
image or multiplanar reconstruction CT is < 18 or > 42 mm.

3. Subject's distal neck diameter, measured outer-wall to outer-wall on a sectional
image or multiplanar reconstruction CT is < 18 or > 42 mm.

4. Subject has prohibitive calcification, occlusive disease, or tortuosity of intended
fixation sites.

5. Subject has circumferential thrombus in region of intended fixation sites.

6. Subject has an increasing tapered proximal neck with ≥ 3 mm increase in diameter from
proximal fixation site to the aneurysm.

7. Subject has a decreasing tapered distal neck with ≥ 3 mm increase in diameter from
distal fixation site to the aneurysm.

8. Subject's aneurysm or distal thoracic aortic neck angle precludes advancement of the
introduction system and device.

9. Subject has an anatomical variance which would compromise circulation to the
carotids, vertebral, or innominate arteries after device placement that is not
amenable to subclavian revascularization. This would not apply to subjects with
occluded celiac arteries.

10. Subject is pregnant.

11. Subject is morbidly obese preventing adequate x-ray visualization of the aorta.

12. Subject has known or suspected connective tissue disorder (e.g., Marfan's syndrome,
Ehlers-Danlos syndrome).

13. Subject has a blood coagulation disorder or bleeding diathesis in which the treatment
cannot be suspended for one week pre and post repair.

14. Subject has coronary artery disease with unstable angina and who has not received
coronary revascularization within the last 3 months.

15. Subject has chronic obstructive pulmonary disease requiring the routine need for
oxygen therapy outside the hospital setting (e.g., daily or nightly home use).

16. Subject is in acute renal failure or renal insufficiency with a creatinine ≥ 2.5
mg/dL and is not on renal replacement therapy or dialysis.

17. Subject has active systemic infection and/or mycotic aneurysms.

18. Subject has had a stroke within 3 months of the treatment date.

19. Subject has less than one-year life expectancy as evidenced by factors prohibiting
major medical intervention (e.g., presence of malignant tumor, advanced age, etc.).

20. Subject is participating in another research study or has received investigational
research study drug or device within 30 days of screening;

21. Subject is confronted with other medical, social or psychological issues that the
investigator believes may interfere with treatment or follow- up. These reasons must
be documented. An example may include adherence to a theological or personal
doctrine with aversion or opposition to blood transfusion.

22. Subject has a co-existing AAA in which the investigator believes requires concomitant
treatment within 45 days.

23. Subject has had a prior AAA repair (endovascular or surgical) that was performed less
than 6 months prior to enrollment.

24. Subject has had a prior endovascular repair (e.g., stent, stent-graft) in the
descending thoracic aorta. The device may not be placed within any prior surgical
graft.

25. Subject has an untreatable allergy or sensitivity to contrast media or device
components.

26. Subject has been admitted to the hospital for a major surgical or medical procedure
within 45 days of the planned procedure or is planning to undergo other major
surgical or medical procedure within 45 days post implantation (e.g., CABG, organ
transplantation, etc.). This excludes any planned procedures for the prospective
stent-graft placement (e.g. common carotid to left subclavian transposition/bypass,
left carotid to axillary bypass, etc. are acceptable. Carotid-carotid bypasses are
not permitted).

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