ClinicalTrials.gg
RecruitingNCT07465627Updated Oct 14, 2026

Vessel Recoil in Specific CLTI Populations

An observational study in Chronic Limb Threatening Ischemia, sponsored by Medical University of Graz. Recruiting at 1 site in Austria. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-14.

Sponsored by Medical University of Graz · Observational

From the registry’s dates

  • Started Jul 2026; still recruiting 4 months later.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
40
Ages
18 Years and older
Sex
All
01

Study summary

Chronic limb threatening ischemia (CLTI) represents the most advanced stage of peripheral arterial disease (PAD) and is characterized by ischemic rest pain, non-healing wounds, or ischemic gangrene. High-risk PAD populations including patients with end-stage renal disease and or diabetes also experience worse outcomes with significantly increased rates of amputation and mortality.

Although some patients with PAD are best treated with a combination of medical management, exercise and lifestyle modification, revascularization is indicated in those with advanced stages of disease and particularly in the presence of CLTI. Revascularization of below-the-knee (BTK) arteries is required for most patients suffering from CLTI, but treatment faces numerous challenges comprising calcification, small vessel size, long-lesion length and early elastic recoil. With regard to these challenges, numerous innovative techniques and devices have been developed within the past decades to optimize endovascular treatment of BTK vessels.

The Spur Peripheral Retrievable Scaffold System (Spur) was developed to directly address many of these pitfalls of infrapopliteal arterial disease. The premise of the design of the Spur is to provide temporary mechanical scaffolding and to prepare the vessel for treatment with a drug-coated balloon (DCB) to enhance drug absorption by creating channels in the endothelium by the deployed Spur.

The objective of this study is to perform a prospective, single-center, single-arm, non-randomized study to evaluate acute vessel recoil following BTK treatment with the Spur Retrievable Scaffold System in combination with a commercially available DCB in specific patients populations. Specific patient populations that are selected to participate in this study are either at high risk to discover unfavorable outcomes with standard techniques due to a high complexity of lesions and/or patients that are not adequately mirrored in available studies. The patient cohorts that will be studied are diabetics and patients on hemodialysis (for at least 6 months). As women are commonly under-represented in comparable trials, this study requires at least 50% of women for each cohort.

The primary endpoint is vessel recoil within 15 minutes post treatment assessed with angiography. Secondary endpoints will be followed out to 12 months.

02

Conditions studied

  • Chronic Limb Threatening Ischemia

Keywords

  • vessel recoil
  • peripheral arterial disease
  • endovascular revascularization
  • below-the-knee
  • chronic limb-threatening ischemia
03

In context

Chronic Limb-Threatening Ischemia

356 studies on the registry are indexed under Chronic Limb-Threatening Ischemia; 71 are open to participants now.

This study's planned enrollment of 40 is below the median of 111 across 102 observational studies indexed under Chronic Limb-Threatening Ischemia.

Browse Chronic Limb-Threatening Ischemia studies →

Lead sponsor

Medical University of Graz is the lead sponsor of 471 studies on the registry; 98 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

Study population

Patients with below-the knee (BTK) peripheral arterial disease (PAD) who are either with chronic kidney disease (CKD) requiring hemodialysis for at least 6 months (cohort 1) and/or diabetics (cohort 2) in Rutherford classes (RC) 4 or 5, with ≥ 50% females in each cohort

Eligibility criteria

General Inclusion Criteria:

  1. Subject is willing and able to provide
  2. Subject is able to comply with the study protocol and with follow-up
  3. >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 (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 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.
Terms in these criteria, in plain language(4)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Life expectancy

The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.

GFR and eGFR (kidney filtering)

GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².

Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
40 participants (estimated)
Patient registry
No

Groups and cohorts

  • CLTI patients on chronic hemodialysis

    Other: Vessel recoil measurement 15 minutes post final treatment (angiographically)

  • CLTI patients with diabetes

    Other: Vessel recoil measurement 15 minutes post final treatment (angiographically)

Interventions

  • OtherVessel recoil measurement 15 minutes post final treatment (angiographically)

    This study will evaluate early recoil following optimized endovascular treatment (Spur Peripheral Retrievable Scaffold System in combination with a DCB) of BTK vessels in specific high-risk patient populations with CLTI.

06

What researchers measure

Primary outcomes

  1. Vessel recoil assessed with angiography

    Time frame: 15 minutes post treatment

Secondary outcomes

  1. Freedom from unplanned major (above the ankle) amputation

    Time frame: Up to 12 months

  2. Freedom from major adverse limb events (MALE)

    Time frame: Up to 12 months

  3. Freedom from all-cause mortality

    Time frame: Up to 12 months

  4. Freedom from clinically driven target lesion revascularisation (CD-TLR)

    Time frame: Up to 12 months

  5. Target vessel patency determined by duplex ultrasound (DUS)

    Time frame: 30 days

  6. Change in ankle brachial index (ABI, or toe brachial index (TBI) alternatively) from baseline

    Time frame: 30 days

  7. Change in Rutherford Class from baseline

    The Rutherford Class (RC) ranges from 0 to 6, with a higher class indicating more severe disease.

    Time frame: 30 days

  8. Change in Wound, Ischemic, and foot Infection score (WIfI) from baseline

    The WIfI score ranges from 0 to 9, with a higher point score indicating more severe disease.

    Time frame: 30 days

07

Study locations

1 of 1 sites recruiting
08

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Updates

1 registry update since Sep 25, 2026
Minor edits
Nothing that changes what the study is or who can join. Edited: date precision
1 update, last Oct 14, 2026
Show all 1 update
  1. Oct 14, 2026
    Minor edits only
    + 1 other change: date precision

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT07465627
Collaborators
ReFlow Medical, Inc.
Responsible party
Sponsor
First posted
Mar 12, 2026
Start date
Jul 1, 2026
Primary completion
Jun 2027 (estimated)
Completion
Sep 2028 (estimated)
Last update
Oct 14, 2026

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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