An observational study in Chronic Limb Threatening Ischemia and Chronic Limb-Threatening Ischemia, sponsored by Cardiovascular and Interventional Radiological Society of Europe. Recruiting at 1 site in United Kingdom. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-23.
Sponsored by Cardiovascular and Interventional Radiological Society of Europe · Observational
ORACLE is a Europe-wide study that will follow 250 people with critical limb-threatening ischemia (CLTI). It aims to see how well orbital atherectomy (OA) works in real-life practice. OA is a procedure that uses a tiny spinning tool to gently remove hard calcium from inside an artery, helping to open the vessel so other treatments-like balloons or stents-can work better. The study focuses on people who have heavily calcified arteries in the femoropopliteal or infrapopliteal areas of the leg.
356 studies on the registry are indexed under Chronic Limb-Threatening Ischemia; 71 are open to participants now.
This study's planned enrollment of 250 is above the median of 111 across 102 observational studies indexed under Chronic Limb-Threatening Ischemia.
Browse Chronic Limb-Threatening Ischemia studies →Cardiovascular and Interventional Radiological Society of Europe is the lead sponsor of 10 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Adult CLTI patients with femoropopliteal or infrapopliteal calcified lesions treated with OA using the Stealth 360 Peripheral OA System for vessel preparation prior to any adjunctive endovascular procedure.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
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.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Eligible patients are those who will undergo OA prior to any adjunctive endovascular procedure
Device: Stealth 360™ Peripheral Orbital Atherectomy System from Abbott
The Stealth 360™ Peripheral Orbital Atherectomy System uses a diamond-coated, eccentrically mounted crown with bi-directional capabilities that treat a wide range of vessels, enabling single device treatment of multiple lesions and vessel sizes.
Also known as: Orbital Atherectomy, Orbital Atherectomy System
Number of lesions with ≤30% residual stenosis after completion of full planned procedure
Defined as residual stenosis ≤30%, immediately after completion of full planned procedure (OA + any planned adjunctive intervention(s)).
Time frame: Immediately after procedure completion
Number of lesions with ≤30% residual stenosis after any unplanned endovascular intervention(s)
Defined as residual stenosis ≤30% immediately after completion of additional unplanned endovascular intervention(s) (any endovascular procedure that was not part of the primary procedure plan).
Time frame: Immediately after procedure completion
Need for unplanned bailout stenting
Defined as any stent placement that was not part of the primary procedure plan.
Time frame: Immediately after procedure completion
Number of participants free from Clinically-Driven Target Lesion Revascularization (CD-TLR)
Defined as freedom from any endovascular re-intervention to the target lesion (± 10 mm) or surgical bypass performed because of restenosis or occlusion of the target lesion.
Time frame: 12 and 24 months
CD-TLR-free survival
Defined as time between first OA procedure and any endovascular re-intervention to the target lesion (± 10 mm) or surgical bypass performed because of restenosis or occlusion of the target lesion.
Time frame: Until the end of the follow-up period of 2 years
Clinical response using Rutherford classification categories
The Rutherford classification is a clinical scale used to categorize the severity of peripheral arterial disease: Category 0 = asymptomatic; Category 1 = mild claudication; Category 2 = moderate claudication; Category 3 = severe claudication; Category 4 = ischemic rest pain; Category 5 = minor tissue loss; Category 6 = severe tissue loss.
Time frame: 12 and 24 months
Wound status
Defined as healing status of the dominant ischemic wound of the target limb (complete, partial, unchanged, worsening).
Time frame: 12 and 24 months
Freedom from amputation of the target limb
Defined as absence of any amputation of the target limb (above ankle).
Time frame: 12 and 24 months
Amputation-free survival
Defined as time between first OA procedure and above-ankle amputation of the target limb.
Time frame: Until the end of the follow-up period of 2 years
Overall survival
Defined as the time between the first OA procedure and death of any cause.
Time frame: Until the end of the follow-up period of 2 years
Patient-reported health-related quality-of-life
Measured by Vascular Quality of Life Questionnaire - 6 items (VascuQol-6), which is a short patient-reported outcome measure (PROM), used to assess health-related quality of life in people with PAD. It consists of 6 questions, each scored from 1 to 7, with 1 as the worst possible quality of life and 7 as the best possible quality of life. Higher overall scores reflect better quality of life for patients with PAD.
Time frame: Baseline, 6, 12 and 24 months post treatment
Frequency and severity of procedural complications and other adverse events
Grading according to the classification system of the Cardiovascular and Interventional Radiological Society of Europe.
Time frame: Within 30 days after the OA procedure
Clinical response using ankle-brachial index (ABI)
The ankle-brachial index (ABI) is a non-invasive measure calculated as the ratio of systolic blood pressure at the ankle to systolic blood pressure at the arm. ABI categories commonly used to classify peripheral arterial disease are: \>1.40 = non-compressible arteries; 1.00-1.40 = normal; 0.91-0.99 = borderline; 0.41-0.90 = mild to moderate peripheral arterial disease; \<0.40 = severe peripheral arterial disease.
Time frame: 12 and 24 months
Clinical response using toe pressure
The toe pressure test measures distal limb perfusion by recording systolic pressure at the toe. In CLTI patients, toe pressure ≤30 mmHg is commonly used to indicate severe ischemia, while values \>30 mmHg suggest better perfusion.
Time frame: 12 and 24 months
Clinical response using WIfi (wound, ischemia and foot infection) score
The WIfI classification is a staging system used to assess CLTI based on wound extent, ischemia severity, and foot infection. Each component is graded from 0 (none) to 3 (severe). Lower WIfI scores indicate a lower risk of limb loss and a lesser urgency for revascularization, whereas higher scores indicate greater disease severity, higher amputation risk, and greater potential benefit from revascularization.
Time frame: 12 and 24 months
Plan to share: No
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