Clinical trial NCT05654103: Comparing Surgical and Endovascular Arteriovenous Fistula Creation
Official title: Randomized Controlled Trial Comparing EndoAVF Versus SurgAVF
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: End Stage Renal Disease on Dialysis
Keywords: hemodialysis
arteriovenous fistula
fistula
endoAVF
End Stage Renal Disease
Lead sponsor: University of California, Los Angeles
Sponsor class: OTHER
Collaborators: name: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
First posted: 2022-12-16
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Maximum age (years): 99
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Randomized controlled trial where participants are assigned to receive a fistula created through surgery (open the skin) or endovascular surgery (through the skin). There is the option to not join the randomized portion and instead join a registry that will track the outcome of a participants fistula.
Primary purpose: TREATMENT

Brief summary: Patients with end-stage kidney disease (ESKD) who use hemodialysis to filter their blood require vascular access for the dialysis machine; the most common type of vascular access is called an arteriovenous fistula (AVF). The AVF is a direct connect between an artery and vein.

Until recently, AVFs were only created through surgery that requires general anesthesia and opening up the skin. Now there are 2 FDA-approved devices designed to create AVFs using endovascular techniques (endoAVF), which means a device that goes through the skin instead of opening the skin up. Also patients are not required to be under general anesthesia, they can receive local anesthesia instead. Due to the relatively new approval of these devices, there is not a randomized study to compare the results of endoAVF versus surgAVF.

This study is a pilot study for an eventually larger scale study to compare the results of endoAVF versus surgAVF. The study aims to determine what the proportion of patients seeking hemodialysis access could qualify for receiving either an endoAVF , surgAVF, or both. Patients who are screened for hemodialysis access must undergo a duplex ultrasound of the blood vessels in the arm to confirm correct sizing. If participants qualify for both procedures they will be randomized to either endoAVF or surgAVF and will track the clinical and patient-reported outcomes of each procedure. Our pilot study hopes to enroll 90 participants. Those outcomes will inform a larger scale study. If the potential participant chooses to abstain from participation in the randomized trial, preferring to decide the method of AVF creation, we will offer to them a chance to join an endoAVF/surgAVF registry that will track the clinical outcomes of the procedure via medical record monitoring.

Detailed description: All individuals being considered for a AVF undergo a procedure called vein mapping. Vein mapping is a duplex ultrasound image of the upper extremity veins to determine whether the veins are suitable for a fistula, the veins have to be large enough with an upper arm vein diameter of ≥ 2.0 mm. The vein mapping is considered standard of care as part of the pre-operative evaluation for vascular access creation.

Potential subjects will have their duplex ultrasound imaging pre-screened to determine whether study anatomical suitability has been met. The vascular surgeons will make the final determination that the patient is a good candidate for a fistula. Those who pass the pre-screen for both endoAVF and surgAVF will be approached at their vascular access appointment to join the trial. If the subject agrees to join and is consented they will be screened further to determine if all other inclusionary/exclusionary criteria have been met, and if screening is satisfactory patients will be randomized by a computer with 50/50 chance of receiving either endoAVF and surgAVF. Those randomized to endoAVF will have to undergo an additional duplex ultrasound imaging that maps the distance between the artery and vein. For subjects who are randomized to endoAVF and who qualify for both devices (WavelinQ and Ellipsys), the decision of which device to use is left to the judgement of the treating physician. The additional vein mapping is done to determine which device can be used for the procedure. If this duplex ultrasound determines that the patient does not qualify for either device, they will be removed from the trial for their own safety and still be paid for the baseline visit. Once the participant has undergone surgery they will be followed for 2 years and undergo routine in-person follow-ups for the first 6 months that will gauge clinical and patient-reported outcomes and perform a physical examination of the fistula. The follow-up visits will be 35 days, 90 days, and 180 days after the initial surgery. The visits will take no more than 45 minutes to complete. There will be monthly chart reviews done to surveille for adverse events, which hemodialysis modality is used, and if secondary procedures are done to facilitate fistula maturation. The monthly chart reviews will happen until the end of the two year period.

Subjects who have signed the consent form yet choose to join the registry instead of the randomized trial will not undergo any extra in-person visits beyond obtaining the initial consent and PHI access authorization as well as a completing a questionnaire on their general vascular access experience which should take no more than 10-15 minutes to complete. The participants will have the clinical outcome of their index endoAVF or surgAVF procedure tracked for up to three years with regular medical record data abstraction

Eligibility criteria: Inclusion Criteria:

* ESKD patients aged ≥ 18 who have chosen hemodialysis as their renal replacement option.
* Ability to give consent to participate in a research study.
* Upper arm vein diameter of ≥ 2.0 mm.

Ellipsys specific inclusion criteria:

* Confirmed radial artery-adjacent vein proximity ≤ 1.5 mm measured lumen edge-to-lumen edge as determined by preprocedural ultrasound and confirmed pre-procedurally.
* Confirmed radial artery and adjacent vein diameter of ≥ 2.0 mm at site where vein and artery connects.

WavelinQ specific inclusion criteria:

* Target vein diameter ≥ 2.0 mm, target artery diameter ≥ 2.0 mm, and ≤ 2 mm between target artery and vein.

Exclusion Criteria:

* People under the age of 18.
* Inability to understand the consent process and/or give consent.
* Upper arm vein diameter less than 2.0 mm making them unsuitable to receive an surgAVF AND endoAVF.
* Patients who are deemed by the surgeon to be anatomic candidates for a forearm vascular access, and the surgeon and the patient determine that a forearm access is the optimal access for the patient, in order to preserve more proximal anatomic sites for future accesses.
* Currently incarcerated individuals.
* Currently pregnant or planning to get pregnant within the next 6 months.
* Individuals who choose peritoneal dialysis over hemodialysis and/or undergoing a kidney transplant within 6 months of randomization.

Primary outcomes:
measure: Physiologically mature fistula
timeFrame: 6 months postoperatively
Secondary outcomes:
measure: clinically mature
timeFrame: 6 months
measure: primary patency
timeFrame: 6 months
measure: secondary patency
timeFrame: 6 months
measure: functional patency
timeFrame: 6 months
measure: Number of interventions to achieve physiologic maturation
timeFrame: 6 months
measure: Number of interventions to achieve clinical maturation
timeFrame: 6 months
Other outcomes:
Locations:
city: Los Angeles
country: United States
facility: UCLA Division of Vascular and Endovascular Surgery Clinic
state: California
city: Pittsburgh
country: United States
facility: University of Pittsburgh Medical Center
state: Pennsylvania
Study officials:
affiliation: University of California, Los Angeles
name: Karen Woo, MD, PhD
role: PRINCIPAL_INVESTIGATOR
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