Clinical trial Recruiting at 1 site Observational Ages 18 and up

Vessel recoil after below-the-knee revascularization in high-risk CLTI patients

Official title: Early Vessel Recoil Following Below-the-knee (BTK) Artery Treatment With the Spur Peripheral Retrievable Scaffold System in Specific Patient Populations With Chronic Limb-threatening Ischemia (CLTI) - The DEEPER CHALLENGE Single Center Prospective Study

Run by Medical University of Graz · NCT07465627 · Data updated 2026-11-12

This study tests how much vessels recoil after a final endovascular treatment in adults with chronic limb-threatening ischemia affecting below-the-knee arteries.

More Chronic Limb-Threatening Ischemia trials

Quick facts

Study typeObservational
Ages18 Years and up
SexAll
Enrollment40 (estimated)
SponsorMedical University of Graz
Academic / other
Locations1 site (Graz)
StatusRecruiting
StartedJuly 1, 2026
Main results expectedJune 2027
Study endsSeptember 2028
Registry record updatedOctober 14, 2026
Trial IDNCT07465627 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults with chronic limb-threatening ischemia and BTK lesions requiring endovascular intervention, who have diabetes or are on chronic hemodialysis, and provide informed consent.

Probably not a fit

Patients without BTK involvement or who do not experience post-procedural recoil variation may see limited direct benefit.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This observational study investigates the extent of vessel recoil measured 15 minutes after the final endovascular treatment in patients with chronic limb-threatening ischemia due to disease in below-the-knee arteries. Eligible participants include adults with limb ischemia symptoms likely requiring endovascular intervention and with disease in BTK vessels confirmed by imaging, who also have diabetes or are on chronic hemodialysis. The primary data point is angiographic recoil, collected soon after treatment, to understand its prevalence and potential impact on outcomes. The study is sponsored by the Medical University of Graz with collaboration from ReFlow Medical, Inc., and is conducted at the Medical University of Graz, Division of Angiology. The findings may inform future device use and procedural strategies in high-risk PAD populations.

Why it matters

Potential benefit: If successful, the study could help tailor endovascular approaches to reduce recoil and improve limb outcomes in high-risk CLTI patients.

How similar studies have gone: Previous work in similar PAD populations has shown that understanding recoil can influence procedural choices, but this exact BTK CLTI recoil assessment is relatively novel.

Who can join: the full rules

Show full inclusion / exclusion criteria
General Inclusion Criteria:

1. Subject is willing and able to provide informed consent
2. Subject is able to comply with the study protocol and with follow-up
3. Life expectancy \>1 year in the investigator's opinion
4. Subject is \> 18 years of age
5. Subject must have symptoms of limb ischemia, determined by clinical symptoms of RC 4 or 5, including rest pain (RC 4) and/or minor tissue loss (RC 5), that in the opinion of the investigator are not amenable to conservative medical therapy and require endovascular intervention for alleviation of symptoms and tissue preservation
6. Subject has stenotic, restenotic or occlusive lesions located in BTK vessels in pre-screening with CTA, MRA or angiography prior to the index procedure.
7. Subject suffers from diabetes and/or receives chronic hemodialysis for KD (for at least 6 months)

   * Diabetes cohort: Subject requires for estimated glomerular filtration rate (eGFR) ≥ 25ml/min (within 30 days of procedure)
   * Hemodialysis cohort: Subject has been receiving hemodialysis treatment for ≥ 6 months. (Note: subjects with diabetes who also receive chronic hemodialysis will be excluded from the diabetes cohort and will be included only in the hemodialysis cohort).

Angiographic Inclusion Criteria:

1. Target lesion can be successfully crossed with a guidewire.
2. Target lesion must be located in BTK arteries. Treatment of the distal popliteal segment (P3) is permitted provided that sizing remains appropriate (no more than 4.5 mm in diameter).
3. Target vessel reconstitutes at or above the medial ankle, with the target treated segment extending no more than 10 mm beyond the ankle.

   1. If the anterior tibial or posterior tibial arteries are treated, there must be inline flow to the foot.
   2. If the peroneal artery is treated, there must be at least one collateral supplying the foot.
4. Target vessel reference diameter is measured to be between 2.5 mm to 4.5 mm in diameter.
5. Only one artery may be treated with the Spur device.

   a. Non-target infrapopliteal lesions requiring treatment must be treated prior to treatment of the target lesion. Treatment of the target vessel/lesion with the Spur device may be performed only if treatment of the non-target vessel(s)/lesion(s) does not result in a complication which may compromise the outflow of the target lesion or result in a major adverse limb event.
6. The treated segment is defined as the total length of artery treated with the Spur device. Total target treatment length must be \< 250mm with a maximum segment of 220 mm separated by 30 mm of healthy tissue between treated lesions.
7. Successful pre-dilatation of the target lesion as outlined in the procedure instructions, defined as resulting in stenosis ≤ 50%, without resulting flow limiting (Type D or greater) dissection, thrombus, or aneurysm by angiography prior to the insertion of the Spur device.
8. Iliac, SFA and popliteal inflow lesions can be treated during the index procedure. Inflow lesions treated intraprocedure must be treated first, prior to consideration of treatment of infrapopliteal lesions. Inflow lesions must have a healthy vessel segment of \>30 mm between the study lesion and the treated segment, defined as ≤ 50% stenosis.
9. The Spur must be deployed from antegrade access.

General Exclusion Criteria:

1. Subject is unwilling or unlikely to comply with the duration of the study (up to 12 months +/-30 days post intervention) in the opinion of the investigator
2. Subject is pregnant or planning to become pregnant during the course of the trial
3. Subject is breastfeeding or planning to breastfeed during the course of the trial
4. Subject has an active and uncontrolled systemic infection, including septicemia or bacteremia
5. Subject has documented active osteomyelitis proximal to the phalanges of the target limb. Osteomyelitis in the digit(s) of the target foot is permitted.
6. Subject has a wound above the ankle and/or a heel wound
7. Subject has planned or had previous major (above the ankle) amputation of the target limb. A planned or previous minor (transmetatarsal amputation or digit amputation) is permitted.
8. Subject with poor and insufficient general condition and/or comorbidities not allowing for endovascular treatment as per the investigator's discretion
9. Diabetes cohort: subject has impaired renal function as defined by an eGFR \< 25 mL/min within 30 days of procedure
10. Hemodialysis cohort: subject has been receiving hemodialysis treatment for less than 6 months
11. Subject with inability to comply with antiplatelet and/or anticoagulation therapy as per the facility's standard of care
12. Subject with known allergies or sensitivities to heparin, antiplatelet drugs, other anticoagulant therapies which do not allow for an adequate peri- and post-procedural treatment
13. Subject with known allergies or sensitivities to Paclitaxel or Sirolimus balloon coatings
14. Subject with known allergies or sensitivities to contrast media that cannot be adequately pre-treated prior to the index procedure
15. Subject with known allergies or sensitivities to nitinol or nickel
16. Subject is currently enrolled in another investigational device or drug trial that interferes with the study endpoints.
17. Subject with prior stent(s) within the target vessel, or bypass surgery of or within the target vessel
18. Subject had previous treatment of the target vessel \<30 days prior to index procedure

Angiographic exclusion criteria:

1. Angiographic evidence of thrombus within target limb
2. Inability to obtain antegrade access in the limb from which the Spur can be deployed
3. Any lesion characteristics, that in the investigator's opinion, would not be amenable to endovascular standard techniques
4. Significant \> 50% stenosis of inflow arteries or unsuccessful treatment of inflow lesions
5. \> 50% stenosis, flow-limiting dissection (Type D or greater), aneurysm or thrombus of the target lesion following pre-dilation
6. Inability to obtain additional imaging 15 minutes after target lesion treatment for recoil evaluation.

Where it's running

  • Medical University of Graz, Division of Angiology
    Graz, Austria
    Recruiting

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.