Endovascular Revascularization for Chronic Carotid Artery Occlusion Trial (ERCAO)

Endovascular Revascularization for Chronic Carotid Artery Occlusion Trial (ERCAO Trial) Part 1: Prospective Clinical Registry Study Part 2: Prospective Randomized Control Trial Study

Revascularization for carotid artery occlusion (CAO) remained controversial, there is no prospective randomized control trial (RCT) regarding carotid artery stenting (CAS) in CAO patients. The investigators conduct a prospective study composed of clinical registry arm and RCT arm. The main purpose of the study is investigate neurocognitive function at 3 months and thereafter up to 12 months.

Study Overview

• Status: Recruiting
• Conditions: Carotid Occlusion
• Intervention / Treatment: Device: Endovascular revascularization

Detailed Description

Carotid artery stenosis is an important cause of stroke. Carotid artery stenting (CAS) provides non-inferior clinical outcome comparing to carotid endarterectomy (CEA). However, revascularization for carotid artery occlusion (CAO) remained controversial, owing to failed extracranial-to-intracranial (EC-IC) artery bypass trials, anatomical hindrance for CEA, and technical limitation for CAS. In the past 10 years, the investigators devoted in endovascular therapy for CAO and published innovative and pilot study results regarding feasibility of CAS for CAO, neurocognitive function (NCF) improvement after successful CAS for CAO, and predictors for CAS success in CAO, all in high-ranking journals. Moreover, successful CAS for CAO would lead to lower mortality and stroke rate during long-term follow-up, according to the preliminary analysis from the investigators. However, there is no prospective randomized control trial (RCT) regarding CAS in CAO patients, and in fact, most of the CAS trials excluded CAO.

The investigators, with the largest volume and experience in CAO recanalization in the world, felt obliged and responsible to propose the following RCT to evaluate endovascular revascularization for chronic CAO.

The study composed of two parts. The first part composed of prospective clinical registry for CAO. The second part compose of a prospective superiority trial, rater blinded, with 1:1 randomization to evaluate the clinical efficacy of interventional therapy for CAO. Eligible candidates for CAO revealed by CT, ultrasonography, angiography, or magnetic resonance imaging (MRI), with abnormal brain perfusion demonstrated by CT perfusion study (CTP) or MRI, will be enrolled in to study. If the participants agreed for randomization, participants will be randomized into 2 groups: the optimal medical therapy (OMT) group and the endovascular revascularization plus optimal medical therapy (ER+OMT) group. The primary end-point of the trial is the NCF improvement at 3 months and thereafter up to 12 months. The secondary endpoint includes: cumulative incidence of death and stroke within 30 days after the procedure; death or ipsilateral stroke between 31 days and 1 year; major stroke, ischemic stroke, or hemorrhagic stroke within 30 days after the procedure; major stroke, ischemic stroke, or hemorrhagic stroke between 31 days and 1 year; cognitive function measured by CANTAB; change of cerebral perfusion measured by CTP; target vessel revascularization rate; technique success rate; procedure success rate; and major procedure complication.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Hsien-Li Kao, MD; Phone Number: 65874 +886-2-2312-3456; Email: hsienli_kao@yahoo.com
• Study Contact Backup: Name: Ying-Hsien Chen, MD; Phone Number: +886-972652463; Email: indiglo314@gmail.com

Study Locations

• Taiwan
  • Taipei, Taiwan, 10002
    • Recruiting
    • National Taiwan University Hospital
    • Contact: Hsien-Li Kao, MD; Email: hsienli_kao@yahoo.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Part 1: Clinical registry study

Inclusion criteria for clinical registry study

• Patient age 20 years or older
• Abnormal cerebral perfusion by CTP or MRI
• No medical history of stroke or transient ischemic attack (TIA) ipsilateral to the carotid occlusion within 90 days of randomization
• Women must not be of childbearing potential or, if of childbearing potential, have a negative pregnancy test prior to randomization.

Exclusion Criteria for clinical registry study

• Patient has acute stroke within 90 days,
• Intolerance or allergic reaction to a study medication without a suitable management alternative.
• Patient is expected to have the ADP antagonist therapy interruption within 3 months after the procedure.
• GI hemorrhage within 1 month prior to enrollment that would preclude antiplatelet therapy
• Bleeding diathesis
• Intracranial hemorrhage within the past 12 months.
• Platelet count <100,000/μl or history of heparin-induced thrombocytopenia.
• Other high-risk cardiac sources of emboli, including left ventricular aneurysm, severe cardiomyopathy, aortic or mitral mechanical heart valve, severe calcific aortic stenosis (valve area < 1.0 cm2), endocarditis, moderate to severe mitral stenosis, left atrial thrombus, or any intracardiac mass, or known unrepaired patent foramen ovale (PFO) with prior paradoxical embolism.
• Any major surgery, major trauma, revascularization procedure within the past 1 month.
• Acute coronary syndrome within the past 1 month or acute coronary syndrome (ACS) that is not amenable to revascularization (patients should undergo planned coronary revascularization at least 30 days before randomization).
• Inability to understand and cooperate with study procedures or provide informed consent.
• Patients with < 5 years life expectancy
• Concomitant vascular conditions precluding endovascular revascularization procedure;
• Previous ipsilateral carotid artery stenting
• Intracranial aneurysm or arteriovenous malformation;
• Educational level lower than elementary school;
• Aphasia or right-sided hemiparesis
• Marked depression.
• Severe dementia.

Part 2: Randomized control study

Inclusion Criteria for randomized control study

• Patient age 20 years or older
• Abnormal cerebral perfusion by CTP or MRI
• No medical history of stroke or TIA ipsilateral to the carotid occlusion within 90 days of randomization
• Patients must have a modified Rankin Scale (mRS) ≤2 at the time of informed consent.
• Women must not be of childbearing potential or, if of childbearing potential, have a negative pregnancy test prior to randomization.
• Randomization will apply to only 1 carotid artery occlusion for patients with bilateral carotid occlusion. Intervention of the contralateral stenosis, should it exists, may be done in according to clinical indications at least 30 days prior to randomization.

Exclusion Criteria randomized control study

• Patient has acute stroke within 90 days,
• Prior major ipsilateral stroke in the past with moderate disability (mRS ≥ 3) that is likely to confound study outcomes.
• Current neurologic illness characterized by fleeting or fixed neurologic deficits that cannot be distinguished from TIA or stroke.
• Patient has significant renal insufficiency with estimated glomerular filtration rate (eGFR) <30 ml/min (at screening). and would not receive renal replacement therapy if contrast agent related nephropathy occurs
• Intolerance or allergic reaction to a study medication without a suitable management alternative.
• Patient is expected to have the ADP antagonist therapy interruption within 3 months after the procedure.
• GI hemorrhage within 1 month prior to enrollment that would preclude antiplatelet therapy
• Bleeding diathesis
• Intracranial hemorrhage within the past 12 months.
• Platelet count <100,000/μl or history of heparin-induced thrombocytopenia.
• Other high-risk cardiac sources of emboli, including left ventricular aneurysm, severe cardiomyopathy, aortic or mitral mechanical heart valve, severe calcific aortic stenosis (valve area < 1.0 cm2), endocarditis, moderate to severe mitral stenosis, left atrial thrombus, or any intracardiac mass, or known unrepaired PFO with prior paradoxical embolism.
• Major (non-carotid) surgery/procedures planned within 3 months after enrollment.
• Any major surgery, major trauma, revascularization procedure within the past 1 month.
• Acute coronary syndrome within the past 1 month or ACS that is not amenable to revascularization (patients should undergo planned coronary revascularization at least 30 days before randomization).
• Coronary artery disease with two or more proximal or major diseased coronary arteries with ≥ 70% stenosis that have not, or cannot, be revascularized.
• Inability to understand and cooperate with study procedures or provide informed consent.
• Patients with < 5 years life expectancy
• Concomitant vascular conditions precluding endovascular revascularization procedure;
• Previous ipsilateral carotid artery stenting
• Intracranial aneurysm or arteriovenous malformation;
• Educational level lower than elementary school;
• Aphasia or right-sided hemiparesis
• Marked depression.
• Severe dementia.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Clinical registry-ER and OMT; In clinical registry setting, participants who selected Endovascular revascularization and optimal medical therapy as the treatment for carotid artery occlusion are enrolled.	Device: Endovascular revascularization; All interventions will be performed via 8F femoral sheath. Target common carotid artery will be engaged with 8F JR 4 guiding catheter. Intra-luminal wiring using coronary guidewires and microcatheters or alternative subintimal tracking with antegrade re-entry technique. Wiring would be abandoned after 30 minutes of futile effort, consumption of more than 300 ml of contrast, or when the wire tip is confirmed to be extravascular. Once wire enters distal true lumen, the microcatheter was exchanged to a 1.5 mm diameter coronary balloon for pre-dilatation. Distal embolic protection device would be deployed if an adequate landing zone can be identified. Properly sized balloon expandable stents and self-expanding stents were then deployed to scaffold the occlusion. Balloon post-dilatation may be done if stent expansion was inadequate.; Other Names: Carotid artery stenting
No Intervention: Clinical registry-OMT; In clinical registry setting, participants who selected optimal medical therapy as the treatment for carotid artery occlusion are enrolled.
Experimental: RCT-ER and OMT; In randomized control trial setting, participants who are randomized to received endovascular revascularization and optimal medical therapy for carotid artery occlusion are enrolled.	Device: Endovascular revascularization; All interventions will be performed via 8F femoral sheath. Target common carotid artery will be engaged with 8F JR 4 guiding catheter. Intra-luminal wiring using coronary guidewires and microcatheters or alternative subintimal tracking with antegrade re-entry technique. Wiring would be abandoned after 30 minutes of futile effort, consumption of more than 300 ml of contrast, or when the wire tip is confirmed to be extravascular. Once wire enters distal true lumen, the microcatheter was exchanged to a 1.5 mm diameter coronary balloon for pre-dilatation. Distal embolic protection device would be deployed if an adequate landing zone can be identified. Properly sized balloon expandable stents and self-expanding stents were then deployed to scaffold the occlusion. Balloon post-dilatation may be done if stent expansion was inadequate.; Other Names: Carotid artery stenting
No Intervention: RCT-OMT; In randomized control trial setting, participants who are randomized to received optimal medical therapy for carotid artery occlusion are enrolled.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
NCF improvement by Alzheimer Disease Assessment Scale-Cognitive subscale (ADAS-Cog)	Neurocognitive function was evaluated by ADAS-Cog	at 3 months and thereafter up to 12 months
NCF improvement by Mini-Mental State Examination (MMSE)	Neurocognitive function was evaluated by MMSE.	at 3 months and thereafter up to 12 months
NCF improvement by verbal fluency test	Neurocognitive function was evaluated verbal fluency test	at 3 months and thereafter up to 12 months
NCF improvement by verbal fluency test Color Trails Test Parts 1	Neurocognitive function was evaluated by Color Trails Test Parts 1	at 3 months and thereafter up to 12 months
NCF improvement by verbal fluency test Color Trails Test Parts 2	Neurocognitive function was evaluated by Color Trails Test Parts 2	at 3 months and thereafter up to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Death and stroke	Cumulative incidence of death and ipsilateral stroke	within 30 days after the procedure and between 31 days and 1 year
Major stroke, ischemic stroke, or hemorrhagic stroke	Cumulative incidence of major stroke, ischemic stroke, or hemorrhagic stroke	within 30 days after the procedure and between 31 days and 1 year
Cambridge Neuropsychological Test Automated Battery (CANTAB)	The CANTAB is a computerized test battery for cognitive function evaluation which has been validated and widely used worldwide. CANTAB tests are simple to administer and show strong correlations to brain constructs and known deficits in various disorders, as well as high sensitivity to interventions and small changes over time. It is designed to be administered by trained psychologists with standardized procedures. Tasks of the CANTAB involving practice and attention, memory, executive function and decision making would be administered to all the participants in this study.	at 3 months and thereafter up to 12 months
Change of cerebral perfusion	Change of cerebral perfusion measured by CT perfusion	at 3 months and thereafter up to 12 months
Target vessel revascularization rate	Target vessel revascularization rate	one year
Technique success rate	Technique success is defined if the occlusion segment was recanalized with final residual diameter stenosis of <20%, and establishing grade 3 antegrade Thrombolysis in Cerebral Infarction (TICI) flow.	30 days
Procedure success rate	Procedure success: the occlusion segment was stented with final residual diameter stenosis of <20%, and establishing grade 3 antegrade TICI flow and without periprocedural complications.	30 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Major procedure complication	Major procedure complication includes intracranial hemorrhage, myocardial infarction, embolic stroke, vascular complication and death during endovascular revascularization or within 30 days after endovascular revascularization.	30 days
Bleeding complication	any bleeding events during the study	one year

Collaborators and Investigators

• Sponsor: National Taiwan University Hospital
• Investigators: Principal Investigator: Hsien-Li Kao, MD, National Taiwan University Hospital

Study record dates

Study Major Dates

• Study Start (Actual): May 17, 2017
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: May 28, 2017
• First Submitted That Met QC Criteria: June 6, 2017
• First Posted (Actual): June 7, 2017

Study Record Updates

• Last Update Posted (Actual): July 28, 2025
• Last Update Submitted That Met QC Criteria: July 23, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: 201702049RINA

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No