Collateral status affects the onset-to-reperfusion time window for good outcome

Area of Science:

• Neurology
• Interventional Radiology
• Stroke Medicine

Background:

• Endovascular thrombectomy (EVT) is a key treatment for acute ischemic stroke.
• Optimizing the time window for EVT is crucial for patient outcomes.
• Collateral status significantly influences stroke progression and treatment response.

Purpose of the Study:

• To define the optimal time window for EVT associated with good functional outcomes.
• To investigate how collateral status modifies the relationship between onset-to-reperfusion time (ORT) and functional outcome.
• To determine if the EVT time window should be adjusted based on collateral status.

Main Methods:

• Retrospective analysis of 554 patients with anterior circulation large artery occlusion treated with EVT.
• Patients were categorized into good and poor collateral groups using CT angiography.
• Statistical analysis assessed the association between ORT, collateral status, and good functional outcome (modified Rankin Scale 0-2).

Main Results:

• Good collateral status (present in 84.5% of patients) and shorter ORT were independently associated with good outcomes.
• The negative impact of delayed reperfusion on good outcomes was significantly steeper in patients with poor collaterals.
• For every 30-minute delay in ORT, the likelihood of a good outcome decreased by 7.4% in the good collateral group versus 69.5% in the poor collateral group.

Conclusions:

• The time window for achieving good outcomes with EVT is influenced by collateral circulation.
• Earlier reperfusion is critical for patients with poor collaterals.
• Consideration of collateral status can help personalize EVT treatment timing for improved functional recovery.