Effect of the Amplifi™ Vein Dilation System on Outflow Vein Dilation and AV Fistula Maturation (AMPLIFI-1)

Inclusion Criteria: 1. Age ≥ 18 years 2. Indicated for wrist or distal forearm radiocephalic AVF creation based on Investigator's standard practice 3. End-Stage Renal Disease (ESRD) receiving maintenance hemodialysis. 4. Baseline cephalic vein diameter between \>1.7 mm and \<3.2 mm at the proposed Study AVF creation site in the distal forearm, with a continuous distal segment or tributary suitable for Amplifi System Outflow Catheter placement, including: * A forearm cephalic vein segment of ≥ 14 cm in length that provides an approximately 10 cm cannulation zone, free of detectable occlusions or stenosis, with collaterals. * Central continuity of the forearm cephalic vein at the elbow demonstrated through one or any combination of the following pathways: 1. the upper arm cephalic vein, 2. the median cubital vein connecting to the upper arm basilic vein, 3. the perforator vein connecting to the deep venous system. * Upper arm veins must show central continuity with no detectable occlusions. 5. Palpable radial artery with a diameter of ≥ 2.0 mm at the site of proposed AVF creation without significant stenosis along the course 6. Positive Allen's Test 7. At least one patent internal jugular vein suitable for Amplifi Inflow Catheter insertion 8. Subject has voluntarily signed written informed consent Exclusion Criteria: 1. Known allergy to Amplifi System components (polyurethane, nitinol), iodinated contrast agents, heparin, or apixaban 2. Known or suspected active infection at the proposed time of Amplifi System placement 3. Known bleeding diathesis, including from uncorrected coagulopathy 4. Known thrombophilia, requiring treatment 5. Hb \<7 gm/dL 6. Platelet level \< 100,000 /mm3 7. Significant radial artery calcification 8. Need for continued treatment with anti-platelet agents or other anticoagulants (other than apixaban) during the Amplifi System treatment period 9. Known history of patent foramen ovale \> 2 mm 10. History of recent intracranial or gastrointestinal bleeding 11. Documented recent central venous or right atrial thrombus 12. Known presence or recent history of intracranial or gastrointestinal bleeding or presence of underlying conditions that would predispose to intracranial or internal bleeding. Documented recent central venous or right atrial thrombus 13. History of recent ipsilateral central venous occlusion, stenosis \> 50%, angioplasty, or stent placement 14. Pregnancy, lactation, or plans to become pregnant during the Study 15. Expected survival less than 12 months 16. Unwillingness or inability to comply with procedures specified in the Protocol, or difficulty or inability to return for follow-up visits as specified by the Protocol 17. Participation in any other investigational drug or medical device study that has not completed primary endpoint evaluation or clinically interferes with the endpoints from the Study, or planned future participation in such studies prior to the completion of the Study