The Merit WRAPSODY™ Endovascular Stent Graft

This is a phase 1 study, designed to evaluate the safety and effectiveness of the WRAPSODY Stent Graft for the treatment of venous outflow circuit obstructions in the veins of the arm or thoracic central veins of subjects who receive chronic dialysis treatment for end stage renal disease.

The study will consist of a screening period in which subject eligibility will be determined. Approximately 50 subjects meeting the study entry criteria will be enrolled. Placement of the WRAPSODY stent graft will follow the procedure. Post study procedure subjects will have planned follow-up visits at 30 days, 3, 6 and 12months, and additional visits as referred by the subject's dialysis facility.

The primary study safety endpoint will be the proportion of subjects without any localized or systemic safety events through 30 days that affect the access or venous outflow circuit and resulted in surgery, hospitalization, or death. Subjects will continue to be followed up to 12 months for supplementary information.

Eligibility Criteria:
Inclusion Criteria:

1. Subject has signed informed consent
2. Subject is ≥ 21 years of age
3. Subject is undergoing chronic hemodialysis or other forms of renal replacement therapy including transplantation and has one of the following being used: a. AV graft placed in the arm ≥30 days prior OR b. Mature fistula in the arm with at least one successful dialysis session completed
4. Angiographic evidence of stenosis
5. The target lesion has ≥ 50% stenosis
6. Subject has clinical or hemodynamic evidence of a venous outflow stenosis or obstruction
7. Full expansion of an appropriately sized standard angioplasty balloon has been achieved during primary angioplasty at the target lesion prior to enrollment

Exclusion Criteria:

1. Subject has undergone an intervention (surgical or percutaneous) of the AVF/AVG \<30 days from the date of the initial study procedure
2. Subject has had a previous stent or stent graft placed in the venous outflow circuit ≤30 days from the date of the initial study procedure
3. Active hemodialysis access is not in the arm
4. A pseudoaneurysm is present within the target lesion
5. Target lesion is in SVC, IJV, under the clavicle, across the elbow, in the needling segment of AVF or AVG anastomosis, located within a stent
6. Lesions, other than the target lesion, in the venous outflow circuit with \>30% stenosis
7. Known or suspected infection of the hemodialysis access site and/or septicemia
8. Permanent pacemaker or automated implantable cardioverter defibrillator (AICD) on the side with the target lesion
9. Current central venous catheter for dialysis access
10. Uncorrectable coagulation disorders
11. Hypersensitivity to nickel titanium alloy
12. The subject is enrolled in another investigational study
13. The subject is unable or unwilling to comply with the protocol requirements
14. Life expectancy is ≤ 12 months
15. Subject cannot receive heparin or equivalent anticoagulant
16. Allergy to radiographic contrast material which cannot be adequately premedicated
17. Subject is pregnant, breastfeeding, or pre-menopausal and intending to become pregnant
18. Subject's access is anticipated to be abandoned within 3 months
19. Subject has a thoracic central vein obstruction that would lead to stent graft placement across the internal jugular vein
20. Subject's hemodialysis access is thrombosed
21. Active malignancy other than non-melanomatous skin cancer
22. Any other condition deemed exclusionary in the opinion of the investigator