Early endovascular treatment for isolated internal carotid artery occlusion

Evaluation of Early Endovascular Treatment in Acute Ischemic Stroke With Isolated Internal Carotid Artery Occlusion (EVT-iICAO)

This trial tests whether giving early endovascular treatment, instead of best medical care alone, helps adults with acute ischemic stroke caused by an isolated internal carotid artery occlusion recover better.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 140 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Sir Run Run Shaw Hospital (Academic / other)
• Locations: 1 site (Hangzhou, Zhejiang)
• Trial ID: NCT07016854 on ClinicalTrials.gov

What this trial studies

This is a prospective, randomized, open-label trial comparing early endovascular treatment (EVT) to best medical treatment in patients with acute ischemic stroke due to isolated internal carotid artery occlusion (iICAO). Eligible adults are randomized within 23 hours of last known well after CT/CTA/CTP or enhanced MRA confirms iICAO without ipsilateral intracranial branch occlusion and shows a target perfusion mismatch. The primary aim is to compare clinical outcomes and safety between arms, with investigators tracking reperfusion rates and functional recovery. The trial addresses a gap in high-level prospective evidence for EVT in this specific occlusion pattern, building on limited retrospective reports.

Who should consider this trial

Good fit: Adults aged 18 or older with acute ischemic stroke due to isolated internal carotid artery occlusion confirmed by CTA/CTP or enhanced MRA within 23 hours, who have a target perfusion mismatch and a NIHSS >5 or disabling deficits are ideal candidates.

Not a fit: Patients unlikely to benefit include those with additional ipsilateral intracranial branch occlusions, those presenting beyond the 23-hour window, patients with non-disabling minor deficits, or those with contraindications to endovascular procedures.

Why it matters

Potential benefit: If successful, early EVT could increase vessel recanalization and improve the chances of functional independence while reducing long-term disability for patients with iICAO-related stroke.

How similar studies have performed: A few retrospective studies have suggested EVT can be effective and safe for iICAO, but high-quality prospective randomized evidence so far is lacking.

Eligibility criteria

Inclusion Criteria:

1. Age ≥18.
2. Clinical signs consistent with an acute ischemic stroke and randomization no later than 23 hours after the time last known to be well.
3. CTP, CTA or enhanced MRA within 1 hour before randomization showed that the offending vessel was isolated internal carotid artery occlusion, namely occlusion of C1-C6 segments (according to Bouthillier's segmentation) at any location. There was no ipsilateral intracranial branch occlusion (T or L shape of internal carotid artery, M1 or M2 segment of middle cerebral artery, A1 or A2 segment of anterior cerebral artery, P1 or P2 segment of posterior cerebral artery).
4. Neurological deficit with a NIHSS of \>5, or ≤5 points with disabling symptoms (complete hemianopsia, severe aphasia, neglect, any limb weakness that cannot sustain resistance to gravity, and functional loss that is considered by doctors and patients to be potentially disabling by clinical evaluation).
5. Mismatch: target Mismatch Profile on CT perfusion or MRI (ischemic core volume is \< 70 ml, mismatch ratio is ≥1.8 and mismatch volume is ≥15 ml); clinical-imaging mismatch defined as an ASPECTS score of more than 5, was present if perfusion data were not available or imaging quality was poor enough to be interpreted.
6. mRS Score before stroke ≤2.
7. Patient/Legally Authorized Representative has signed the Informed Consent form.

Exclusion Criteria:

1. The patient underwent carotid endarterectomy within 1 month.
2. Severe comorbid condition with life expectancy less than 6 months at baseline.
3. Other suspected cerebrovascular diseases (vasculitis, untreated cerebrovascular malformation, intracranial aneurysm, etc.) based on history and CTA/MRA.
4. Women who are pregnant or planning to become pregnant at the time of the study and who are known to be pregnant or breastfeeding at the time of admission.
5. Known life-threatening allergic reactions to contrast media or intravascular products.
6. Chronic internal carotid artery occlusion, defined as known carotid artery occlusion (imaging examination) ≥30 days before randomization or highly suspected chronic internal carotid artery occlusion based on medical history and CT/MRI.
7. Tandem occlusion, which was defined as internal carotid artery occlusion combined with large intracranial vessel occlusion (T or L shape of internal carotid artery, M1 or M2 segment of middle cerebral artery, A1 or A2 segment of anterior cerebral artery, P1 or P2 segment of posterior cerebral artery).
8. No known vascular access.
9. Suspected aortic dissection based on medical history, clinical evaluation or/and imaging.
10. Evidence of intracranial hemorrhage on CT/MRI.
11. Patient unable to come or unavailable for follow-up.
12. Pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluations.
13. Seizures at stroke onset if they make the diagnosis of stroke doubtful and preclude obtaining an accurate baseline NIHSS assessment.
14. Patients have contraindications to the use of heparin and antiplatelet drugs.

Where this trial is running

Hangzhou, Zhejiang

• Sir Run Run Shaw Hospital — Hangzhou, Zhejiang, China (Recruiting)

Conditions Stroke, Acute Ischemic; endovascular treatment; isolated internal carotid artery occlusion