Acute ischemic stroke: The role of emergency carotid endarterectomy in isolated extracranial internal carotid artery occlusion.

Objectives: The treatment of choice for acute and isolated extracranial internal carotid artery (eICA) occlusion remains, to date, controversial. Although intravenous thrombolysis is recommended, its effectiveness is generally low. This retrospective study aims to assess the clinical outcome and the role of CT perfusion in symptomatic patients who underwent carotid endarterectomy (CEA) for acute occlusion of the eICA.

Materials and methods: All the 21 patients presented with stroke-in-evolution, complete patency of intracranial circulation, no evidence of hemorrhagic transformation at CT and a minimum ASPECTS of 6. Clinical improvement was assessed by evaluating the variation of NIHSS and the mRS. We investigated the relationship between NIHSS and the timing of the surgery, the ASPECT score, and the volume of ischemic penumbra at CT perfusion.

Results: Median NIHSS on admission was 9 (range 1-24) and it decreased to 4 (range 0-35) 24 h after surgery, improving in 76.2% of patients. Patients with an ASPECTS of 6 (3 patients) showed an improvement of 66.7%, while it was of 81.8% in those starting with a score of 9 or 10 (11 patients). A mRS between 0 and 2 after 3 months was achieved in 12 out of 21 patients. The average time elapsing between surgery and symptom onset was 410 min (range 70-1070 min). Fourteen patients treated within 8 h from symptoms onset showed a clinical improvement of 85.7%, compared to a 57.1% for those which underwent later surgery. Four patients underwent thrombolytic therapy before CEA showing postoperative clinical improvement and no intracranial hemorrhage. Among the 14 patients who underwent CT perfusion, the median ischemic penumbra volume was 112 cc in those with clinical improvement (10 patients) and only 84 cc in those with worse clinical outcomes (4 patients).

Conclusions: Emergency CEA in isolated eICA occlusion has proved to be a safe and effective treatment option in selected patients. CT perfusion, imaging the ischemic penumbra and quantifying the tissue suitable for reperfusion, offers a valid support in the diagnostic-therapeutic workup. Indeed, we can infer that the area of the ischemic penumbra is directly proportional to the margin of clinical improvement after revascularization, supposing that the appropriate intervention timing is respect.