Chronic Limb-Threatening IschemiaIMAGE-BTKNCT07731997
IVUS Guidance in BTK Interventions
A study testing Intravascular ultrasound-guided EVT and Angiography-guided EVT in people with Chronic Limb-Threatening Ischemia, run by Shin Kong Wu Ho-Su Memorial Hospital at 4 sites in Taiwan.
Trial summary
Chronic limb-threatening ischemia (CLTI) is a severe form of peripheral artery disease in which very poor blood flow in the arteries below the knee can cause rest pain, non-healing wounds, and even loss of the limb. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Chronic Limb-Threatening Ischemia
- What is being tested?
- Intravascular ultrasound-guided EVT and Angiography-guided EVT
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 212 participants
- Where
- 4 sitesTaiwan
- Study dates
- Aug 2026to Jul 2030
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age ≥18 years.
- Documented chronic limb-threatening ischemia, meeting the following criteria according to guidelines(13):
- Presence of ischemic symptoms compatible with CLTI, defined as arterial insufficiency with gangrene, non-healing ischemic ulcer, or rest pain consistent with Rutherford classes 4-5 AND
- Imaging evidence within the past 12 months showing atherosclerotic PAD, including CTA, MRA, angiography or duplex ultrasound AND
- Ankle-Brachial Index (ABI) ≤0.80 or Toe-Brachial Index (TBI) ≤0.60 for patients who never underwent revascularization; ABI ≤0.85 or TBI ≤0.65 for those with history of prior revascularization procedures OR
- Ischemic rest pain alone (Rutherford class 4) with ankle systolic pressure <50 mmHg, toe pressure of <30 mmHg, transcutaneous PO2 of <30 mmHg, or flat-line transtarsal pulse volume recording OR
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- Tissue loss with or without ischemic rest pain (Rutherford class 5) with ankle systolic pressure <70 mmHg, toe pressure of <50 mmHg, transcutaneous PO2 of <30 mmHg, or flatline transtarsal pulse volume recording
- Absence of occlusive upstream disease, defined by the following:
- Demonstrated vascular patency from the aorta to the second segment of the popliteal artery (P2), either by angiography, duplex ultrasound, CTA or MRA within the last 7 days prior to randomization
- In patients who underwent prior treatment for upstream disease, there are no restrictions in treatment modalities received as long as patency is demonstrated as previously defined
- If upstream disease is planned to be treated in the same index procedure, technically successful treatment of the upstream vessels must be achieved before randomization, defined as less than 30% residual stenosis and no flow-limiting dissections
- Informed Consent:
- Demonstrated ability and willingness to adhere to the study protocol and provide written informed consent
Who cannot join
- Age <18 years
- Asymptomatic or mild disease: patients who underwent revascularization for disease graded Rutherford classes 0-3
- Patients with major tissue loss (Rutherford 6) in whom major amputation was planned at the time of screening
- Patient with a history of prior major (above-the-ankle) amputation of the study limb
- Unable to tolerate any antiplatelet agent or with severe bleeding diathesis
- Clinical signs of active, uncontrolled, severe limb infection or septicemia, defined as fever exceeding 38.5°C, a white blood cell count above 15,000 cells/µL, or hypotension, at the time of screening (this does not include osteomyelitis confined to the phalanges or metatarsal heads or foot cellulitis treatable with IV antibiotics at the time of revascularization)
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- Acute coronary syndrome or acute stroke within 30 days of screening
- Active hepatitis or severe liver cirrhosis (Child Pugh C)
- Advanced CKD (defined with eGFR<30 mL/min/1.73m2) or end-stage renal disease
- Pregnancy, breastfeeding, or women of childbearing potential who are not using an effective method of contraception
- Previous (within 30 days) or concomitant participation in another clinical study with investigational medicinal product(s) that has not yet reached its primary endpoint
- Life expectancy <1 year
Trial locations and contacts
4 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Taiwan4 sites
Chi Mei Medical Center
Tainan, 710
Chon-Seng Hong, MD, +886-6-281-2811, Ahsingsing@gmail.com
National Taiwan University Hospital
Taipei, 100
Jen-Kuang Lee, MD, PhD, +886-2-2312-3456, b85401104@gmail.com
Shin Kong Wu Ho-Su Memorial Hospital
Taipei, 111
Donna SH Lin, MD, +886-2-2833-2211, donna.lin24@gmail.com
Linkou Chang Gung Memorial Hospital
Taoyuan, 333
Chun-Chi Chen, MD, +886-3-328-1200, mr3228@gmail.com
About this study
Official title: Intravascular Ultrasound IMaging vs Angiography-Guided EVT in Below-the-Knee Arteries
Chronic limb-threatening ischemia (CLTI) is a severe form of peripheral artery disease in which very poor blood flow in the arteries below the knee can cause rest pain, non-healing wounds, and even loss of the limb. It is often treated with endovascular therapy (EVT), a minimally invasive procedure that opens the blocked artery, but the artery frequently narrows or closes again afterward. These procedures are usually guided by X-ray pictures taken with dye (angiography). Intravascular ultrasound (IVUS) is an imaging tool that uses a small catheter inside the artery to give a more detailed view of the vessel, which may help doctors open it more completely. It is not yet clear whether adding IVUS improves results below the knee.
This study is testing whether guiding treatment with IVUS plus angiography keeps the artery open better than angiography alone. Adults aged 18 or older with CLTI who are having endovascular therapy for a blocked artery below the knee may take part. Participants are assigned by chance to be treated with either both imaging methods or angiography alone, and are followed for 12 months. The main question is how well the treated artery stays open at 6 months; researchers will also compare repeat procedures, amputation, complications, wound healing, survival, and quality of life.
- Conditions
- Chronic Limb-Threatening Ischemia
- Being tested
- Intravascular ultrasound-guided EVT, Angiography-guided EVT
- Keywords
- IMAGE-BTK, Chronic limb-threatening ischemia, Peripheral artery disease, Endovascular therapy, Intravascular ultrasound, Primary patency
- Medical subject headings
- Chronic Limb-Threatening Ischemia, Peripheral Arterial Disease
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Intravascular ultrasound-guided EVTProcedure or surgery
Endovascular therapy of the below-the-knee artery is guided by intravascular ultrasound (IVUS) imaging in addition to X-ray angiography, with IVUS used to assess the lesion, size and select devices, optimize treatment, and confirm the final result.
Angiography-guided EVTProcedure or surgery
Endovascular therapy of the below-the-knee artery is guided by X-ray angiography with contrast dye alone, without the use of intravascular ultrasound, to assess the lesion, size and select devices, and judge the final result.
| Study group | Role | What they receive |
|---|---|---|
| IVUS + Angiography-guided EVT | Experimental | Not described Receives: Procedure: Intravascular ultrasound-guided EVT |
| Angiography-guided EVT | Active comparator | Not described Receives: Procedure: Angiography-guided EVT |
What is being measured
The primary outcome is the main question the study is designed to answer.
Primary patency at 6 months
Freedom from clinically driven target lesion revascularization (CD-TLR), total occlusion of the target vessel, or binary restenosis of the target lesion. Binary restenosis is defined as a peak systolic velocity ratio >2.0 on duplex ultrasound. Reported as the proportion of participants meeting all three criteria.
Measured: 6 months after the index procedure
Secondary outcomes (18)
Major amputation of the study limb
Proportion of participants undergoing major (above-the-ankle) amputation of the study limb.
Measured: 12 months
Major adverse limb events (MALE)
Proportion of participants with a major adverse limb event, defined as a composite of above-ankle amputation of the study limb, CD-TLR, or all-cause mortality.
Measured: 12 months
Composite freedom from limb events
Proportion of participants free from all of the following: major amputation of the study limb, total occlusion of the target vessel, CD-TLR, and binary restenosis of the target lesion (peak systolic velocity ratio >2.0 on duplex ultrasound).
Measured: 12 months
Wound healing (Rutherford class 5 participants)
Wound healing rate, reported as the proportion of Rutherford class 5 participants with complete healing of the index wound.
Measured: 1, 3, 6, 9, and 12 months
Time to complete wound healing (Rutherford class 5 participants)
Time to complete wound healing, reported as the time since the index procedure to complete healing of the index wound in Rutherford class 5 participants.
Measured: From the index procedure to 12 months
Major adverse cardiovascular events (MACE)
Proportion of participants with a major adverse cardiovascular event, defined as a composite of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death, and each component reported individually.
Measured: 12 months
Acute limb ischemia
Proportion of participants with an acute limb ischemia event in the study limb.
Measured: 12 months
Limb-related mortality
Proportion of participants who die from a limb-related cause.
Measured: 12 months
All-cause mortality
Proportion of participants who die from any cause.
Measured: 12 months
Periprocedural complications
Proportion of participants with any periprocedural complication (e.g., dissection, perforation, distal embolization, access-site complication, or contrast-related event) related to the index procedure.
Measured: During the index procedure through 30 days
Disagreement in imaging findings between angiography and IVUS
Proportion of treated lesions in which intravascular ultrasound (IVUS) findings differ from angiographic findings, as assessed by the core laboratory (including differences in vessel diameter, lesion length, degree of stenosis, plaque or calcium characterization, or identification of dissection or under-expansion).
Measured: During the index procedure (Day 0)
Procedural success
Proportion of participants achieving procedural success, defined as successful revascularization of the target lesion with residual stenosis below the pre-specified threshold and no major periprocedural complication.
Measured: During the index procedure (Day 0)
Procedure time
Total time of the index endovascular procedure, in minutes.
Measured: During the index procedure (Day 0)
Contrast use
Total volume of iodinated contrast used during the index procedure, in milliliters.
Measured: During the index procedure (Day 0)
Change in quality of life
Change from baseline in health-related quality of life, measured with one generic and two disease-specific instruments:
- EQ-5D-5L (EuroQol 5-Dimension 5-Level): the descriptive system yields an index value ranging from less than 0 to 1 (1 = full health; higher scores = better quality of life), accompanied by the EQ Visual Analogue Scale scored 0 to 100 (higher = better health).
- VascuQoL-6 (Vascular Quality of Life Questionnaire, 6-item): total score ranges from 6 to 24 (higher scores = better quality of life).
- WIQ (Walking Impairment Questionnaire): score ranges from 0 to 100 (higher scores = better, i.e., less walking impairment).
Measured: Baseline, 1, 3, 6 and 12 months
Change in ankle-brachial index
Change from baseline in ankle-brachial index (ABI)
Measured: Baseline, 1, 3, 6, 9 and 12 months
Change in toe-brachial index
Change from baseline in toe-brachial index (TBI)
Measured: Baseline, 1, 3, 6, 9 and 12 months
Change in transcutaneous oxygen pressure
Change from baseline in transcutaneous oxygen pressure (TcPO2)
Measured: Baseline, 1, 3, 6, 9 and 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jul 2026
- Study startAug 2026 (estimated)
- Primary completionJul 2030 (estimated)
- Study completionJul 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Chronic Limb-Threatening IschemiaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 212 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Shin Kong Wu Ho-Su Memorial Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- National Taiwan University Hospital, Chi Mei Medical Hospital, Chang Gung Memorial Hospital, Taipei Veterans General Hospital, Taiwan
- Responsible party
- Principal investigator, Donna Shu-Han Lin, Shin Kong Wu Ho-Su Memorial Hospital
- Investigators
- Donna SH Lin, MD, Principal investigator, Shin Kong Wu Ho-Su Memorial Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07731997
- Sponsor's protocol ID
- 20251224R
- Acronym
- IMAGE-BTK
- Status last verified
- Jul 2026
- First submitted
- 17 Jul 2026
- Last updated
- 28 Jul 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Intravascular Ultrasound IMaging vs Angiography-Guided EVT in Below-the-Knee Arteries
- ClinicalTrials.gov ID
- NCT07731997
- Acronym / sponsor ID
- IMAGE-BTK / 20251224R
- Conditions
- Chronic Limb-Threatening Ischemia
- Keywords
- IMAGE-BTK, Chronic limb-threatening ischemia, Peripheral artery disease, Endovascular therapy, Intravascular ultrasound, Primary patency
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 212 participants (estimated)
- Lead sponsor
- Shin Kong Wu Ho-Su Memorial HospitalUniversity, hospital or other
- Collaborators
- National Taiwan University Hospital, Chi Mei Medical Hospital, Chang Gung Memorial Hospital, Taipei Veterans General Hospital, Taiwan
- Study start
- Aug 2026 (estimated)
- Primary completion
- Jul 2030 (estimated)
- Study completion
- Jul 2030 (estimated)
- First posted
- 28 Jul 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Chronic limb-threatening ischemia (CLTI) is a severe form of peripheral artery disease in which very poor blood flow in the arteries below the knee can cause rest pain, non-healing wounds, and even loss of the limb. It is often treated with endovascular therapy (EVT), a minimally invasive procedure that opens the blocked artery, but the artery frequently narrows or closes again afterward. These procedures are usually guided by X-ray pictures taken with dye (angiography). Intravascular ultrasound (IVUS) is an imaging tool that uses a small catheter inside the artery to give a more detailed view of the vessel, which may help doctors open it more completely. It is not yet clear whether adding IVUS improves results below the knee.
This study is testing whether guiding treatment with IVUS plus angiography keeps the artery open better than angiography alone. Adults aged 18 or older with CLTI who are having endovascular therapy for a blocked artery below the knee may take part. Participants are assigned by chance to be treated with either both imaging methods or angiography alone, and are followed for 12 months. The main question is how well the treated artery stays open at 6 months; researchers will also compare repeat procedures, amputation, complications, wound healing, survival, and quality of life.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| IVUS + Angiography-guided EVT | Experimental | Procedure: Intravascular ultrasound-guided EVT |
| Angiography-guided EVT | Active comparator | Procedure: Angiography-guided EVT |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (13 listed)
- Age ≥18 years.
- Documented chronic limb-threatening ischemia, meeting the following criteria according to guidelines(13):
- Absence of occlusive upstream disease, defined by the following:
- Informed Consent:
Key exclusion criteria (12 listed)
- Age <18 years
- Asymptomatic or mild disease: patients who underwent revascularization for disease graded Rutherford classes 0-3
- Patients with major tissue loss (Rutherford 6) in whom major amputation was planned at the time of screening
- Patient with a history of prior major (above-the-ankle) amputation of the study limb
- Unable to tolerate any antiplatelet agent or with severe bleeding diathesis
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Intravascular ultrasound-guided EVTEndovascular therapy of the below-the-knee artery is guided by intravascular ultrasound (IVUS) imaging in addition to X-ray angiography, with IVUS used to assess the lesion, size and select devices, optimize treatment, and confirm the final result. | Procedure or surgery | IVUS + Angiography-guided EVT |
| Angiography-guided EVTEndovascular therapy of the below-the-knee artery is guided by X-ray angiography with contrast dye alone, without the use of intravascular ultrasound, to assess the lesion, size and select devices, and judge the final result. | Procedure or surgery | Angiography-guided EVT |
Primary outcome
Primary patency at 6 months
Time frame: 6 months after the index procedure
Freedom from clinically driven target lesion revascularization (CD-TLR), total occlusion of the target vessel, or binary restenosis of the target lesion. Binary restenosis is defined as a peak systolic velocity ratio >2.0 on duplex ultrasound. Reported as the proportion of participants meeting all three criteria.
18 secondary outcomes
Major amputation of the study limb
Time frame: 12 months
Major adverse limb events (MALE)
Time frame: 12 months
Composite freedom from limb events
Time frame: 12 months
Wound healing (Rutherford class 5 participants)
Time frame: 1, 3, 6, 9, and 12 months
Time to complete wound healing (Rutherford class 5 participants)
Time frame: From the index procedure to 12 months
Major adverse cardiovascular events (MACE)
Time frame: 12 months
Acute limb ischemia
Time frame: 12 months
Limb-related mortality
Time frame: 12 months
All-cause mortality
Time frame: 12 months
Periprocedural complications
Time frame: During the index procedure through 30 days
Disagreement in imaging findings between angiography and IVUS
Time frame: During the index procedure (Day 0)
Procedural success
Time frame: During the index procedure (Day 0)
Procedure time
Time frame: During the index procedure (Day 0)
Contrast use
Time frame: During the index procedure (Day 0)
Change in quality of life
Time frame: Baseline, 1, 3, 6 and 12 months
Change in ankle-brachial index
Time frame: Baseline, 1, 3, 6, 9 and 12 months
Change in toe-brachial index
Time frame: Baseline, 1, 3, 6, 9 and 12 months
Change in transcutaneous oxygen pressure
Time frame: Baseline, 1, 3, 6, 9 and 12 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jul 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Donna SH Lin, MD principal investigator
Shin Kong Wu Ho-Su Memorial Hospital
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Intravascular ultrasound-guided EVT and Angiography-guided EVT in people with Chronic Limb-Threatening Ischemia, run by Shin Kong Wu Ho-Su Memorial Hospital at 4 sites in Taiwan.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 13 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 28 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in Taiwan. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Donna SH Lin, MD (+886-2-2833-2211, donna.lin24@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Primary patency at 6 months (time frame: 6 months after the index procedure). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Jul 2026.