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Recurrent Hemispheric Stroke Syndromes in Symptomatic Atherosclerotic Internal Carotid Artery Occlusions: The Carotid
Fadi Nahab1, Michael Liu1, Haseeb A Rahman1
1Emory University, Atlanta, Georgia.
Insights
Extracranial-intracranial bypass surgery did not improve outcomes for patients with recurrent hemispheric syndromes from atherosclerotic internal carotid artery occlusion. Aggressive risk factor management is crucial for preventing recurrent strokes in these individuals.
Area of Science:
- Neurology
- Neurosurgery
- Vascular Surgery
Background:
- Limited data exist on the effectiveness of extracranial-intracranial (EC-IC) bypass for patients experiencing recurrent hemispheric syndromes due to atherosclerotic internal carotid artery occlusion (AICAO).
- Recurrent strokes in AICAO patients pose significant challenges, necessitating evaluation of surgical interventions like EC-IC bypass.
Purpose of the Study:
- To compare the clinical outcomes and efficacy of EC-IC bypass surgery in patients with and without recurrent hemispheric syndromes associated with AICAO.
- To analyze the impact of EC-IC bypass on stroke and death rates within the context of the Carotid Occlusion Surgery Study (COSS).
Main Methods:
- The Carotid Occlusion Surgery Study (COSS) enrolled patients with AICAO, comparing surgical EC-IC bypass to medical management.
- Participants were categorized based on the presence (rHEMI+) or absence (rHEMI-) of recurrent hemispheric ischemia prior to randomization.
- The primary outcome measured was the occurrence of all strokes and death within 30 days post-randomization and ipsilateral ischemic stroke within 2 years.
Main Results:
- Of 195 randomized participants, 100 had recurrent hemispheric syndromes (rHEMI+).
- rHEMI+ patients were more likely to have had a prior stroke or transient ischemic attack (TIA) as their entry event.
- No significant difference in the primary endpoint (ipsilateral ischemic stroke) was observed between surgical and nonsurgical groups in either rHEMI+ or rHEMI- cohorts.
Conclusions:
- EC-IC bypass surgery did not demonstrate a significant benefit over medical treatment for patients with recurrent hemispheric stroke syndromes due to AICAO in the COSS trial.
- Prioritizing early and aggressive risk factor modification is essential for reducing the incidence of recurrent strokes in this patient population.
Background:
There are limited data on outcomes of extracranial-intracranial (EC-IC) bypass in patients with recurrent hemispheric syndromes due to atherosclerotic internal carotid artery occlusion (AICAO).
Objective:
To compare clinical outcomes and efficacy of EC-IC bypass surgery in patients with and without recurrent hemispheric syndromes associated with AICAO in the Carotid Occlusion Surgery Study (COSS).
Methods:
In patients enrolled in the COSS trial, we compared baseline characteristics and clinical outcomes for participants with (rHEMI+) and without recurrent hemispheric ischemia (rHEMI-) prior to randomization into surgical vs medical groups. The primary outcome was all stroke and death from randomization through 30 d and ipsilateral ischemic stroke within 2 yr.
Results:
Of 195 randomized participants, 100 were rHEMI+ (50 in each group). Baseline characteristics between rHEMI+ and rHEMI- participants were similar except rHEMI+ were more likely to have had previous stroke prior to randomization (61% vs 20%, P < .01) and to have TIA as the entry event (59% vs 21%, P < .01). All primary endpoints were ipsilateral ischemic strokes. There were no significant differences in occurrence of the primary endpoint between nonsurgical and surgical participants in rHEMI+ (26.3% vs 22.4%, P = .660) and rHEMI- (18.9% vs 19.5%, P = .943). For nonsurgical participants, there was no significant difference in the primary endpoint for rHEMI+ vs rHEMI- patients (P = .410).
Conclusion:
Patients with recurrent hemispheric stroke syndromes enrolled in the COSS trial did not show benefit from EC-IC bypass compared to medical treatment. Early aggressive risk factor measures should be prioritized to reduce recurrent strokes in these patients.
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