Carotid Artery Occlusion, Chronic Internal Carotid Artery Occlusion
Conditions
Brief summary
Chronic carotid artery occlusion is an important cause of ischemic stroke. Even with best medical therapy, patients with symptomatic disease may continue to have recurrent ipsilateral transient ischemic attack or ischemic stroke and may have a substantial burden of cognitive decline. Advances in guidewires, microcatheters, distal protection devices, and endovascular techniques have improved the technical success of CCAO recanalization; however, the overall clinical benefit of endovascular therapy appears highly dependent on patient selection and intra-procedural decision-making. During endovascular recanalization, once the guidewire crosses the occluded segment, the operator often must determine whether intraluminal thrombus, dissection, plaque debris, or other lesions are present. Digital subtraction angiography is essential for lumen and flow assessment but cannot reliably characterize the tissue composition or age of intraluminal filling defects. OCT provides high-resolution intraluminal imaging and may improve thrombus identification and lesion assessment in this setting.
Detailed description
OCT is one of the highest-resolution intravascular imaging modalities, with axial resolution in the range of approximately 10-20 um. Compared with intravascular ultrasound, OCT can more clearly demonstrate vessel wall layering, plaque components, thrombus surface morphology, signal attenuation, and intraluminal structural detail. In carotid intervention, published clinical experience suggests that OCT may help define thrombus boundaries, characterize thrombus morphology, guide stent landing zones, inform use of protection devices, and support peri-procedural antithrombotic decisions. The clinical value of OCT thrombus typing remains incompletely established. Coronary OCT studies have reported good discrimination of thrombus type using image attenuation, backscatter, and grayscale parameters, whereas other studies comparing acute OCT findings with histopathology have not confirmed reliable prediction of thrombus composition or freshness. These conflicting data indicate that OCT thrombus classification should be validated prospectively within the specific clinical context of CCAO recanalization rather than extrapolated from coronary studies or isolated case reports.
Interventions
None listed
Sponsors
RenJi Hospital
Study design
Observational model
COHORT
Time perspective
OTHER
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
1. Age 18-80 years, male or female. 2. Symptomatic chronic carotid artery occlusion, with atherosclerosis as the main etiology and disease duration of at least 3 weeks. 3. Persistent symptoms despite best medical therapy, including ipsilateral TIA or stroke, or imaging evidence of ipsilateral hypoperfusion. 4. Clinically planned endovascular recanalization procedure in which the guidewire successfully crosses the occluded segment. 5. Intra-procedural OCT intraluminal imaging is planned or completed. 6. The operator judges that OCT imaging will not substantially increase immediate rescue risk and that peri-procedural safety observation can be completed. 7. Baseline mRS score 0-2, NIHSS \<=15, and ASPECTS \>=6. 8. Target vessel anatomy can support endovascular recanalization and stent therapy if clinically necessary. 9. Written informed consent has been signed before the procedure and includes OCT imaging and follow-up requirements.
Exclusion criteria
* 1.Intra-procedural clinical condition requires immediate rescue treatment, preventing protocol-defined OCT imaging or safety recording. 2.Flow-limiting dissection, vascular rupture, or another serious complication requiring immediate rescue treatment occurs before OCT examination. 3.Non-atherosclerotic etiology, including arterial dissection, moyamoya disease, vasculitis, or radiation-induced vascular injury. 4.Ipsilateral intracranial large vessel occlusion requiring priority treatment. 5.Severe coagulation disorder, including platelet count \<80 x 10\^9/L or INR \>2.0. 6.Known contraindication or severe allergy to iodinated contrast, required peri-procedural antithrombotic medication, or OCT-related flushing or contrast procedures. 7.Large cerebral infarction, defined as ASPECTS \<6 or DWI infarct volume \>70 mL. 8.Severe target vessel calcification or tortuosity such that the OCT catheter is not expected to pass safely or the recanalization risk is judged to be extremely high. 9.eGFR \<30 mL/min or severe hepatic dysfunction. 10.Life expectancy \<12 months. 11.Pregnancy or lactation. 12.Current participation in another conflicting clinical study that may affect outcome assessment.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Composite Rate of Procedure-Related Adverse Events | 7days after operation | Percentage of participants experiencing one or more of the following procedure-related complications during or after OCT-guided CCAO recanalization: 1. OCT-related vascular injury (dissection/perforation on DSA) 2. Distal embolization (angiographic occlusion) 3. Symptomatic intracranial hemorrhage (CT/MRI confirmed with NIHSS increase ≧ 4） 4. Cerebral hyperperfusion syndrome (clinical symptoms + CT perfusion/TCD confirmation) 5. Contrast-induced nephropathy (serum creatinine increase ≧ 25% or ≧0.5 mg /dL from baseline) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Rate of Successful Vessel Recanalization | immediately after operation | Percentage of participants achieving successful recanalization of the chronically occluded internal carotid artery, defined as Modified Treatment in Cerebral Ischemia (mTICI) grade 2b or 3, assessed by post-procedural Digital Subtraction Angiography (DSA). |
| Change from Baseline in National Institutes of Health Stroke Scale (NIHSS) Score | immediately after operation | Mean change in NIHSS score to measure the severity of stroke-related neurological deficits. The total score ranges from 0 to 42, where higher scores indicate more severe neurological impairment. |
| Total Procedural Duration | immediately after operation | Total time taken to complete the intervention, measured from initial arterial puncture to sheath removal or completion of angiography. |
| Total Volume of Contrast Medium Administered | immediately after operation | The cumulative volume of iodinated contrast agent used throughout the procedure. |
Countries
China
Outcome results
None listed