Mechanical thrombectomy for large vessel occlusion strokes beyond 24 hours

Area of Science:

• Neurology
• Interventional Neurology
• Stroke Medicine

Background:

• Mechanical thrombectomy is a proven treatment for large vessel occlusion (LVO) within 24 hours.
• The efficacy and safety of thrombectomy beyond this standard window require further investigation.

Purpose of the Study:

• To evaluate the safety and effectiveness of mechanical thrombectomy for LVO in patients treated beyond the established 24-hour window.
• To compare outcomes of thrombectomy performed beyond 24 hours with those within the 6-24 hour window.

Main Methods:

• Retrospective review of the multicenter Stroke Thrombectomy and Aneurysm Registry (STAR).
• Identified patients undergoing thrombectomy for LVO beyond 24 hours.
• Matched a control group of patients who underwent thrombectomy within the 6-24 hour window (2:1 ratio).
• Primary outcome: functional independence at 3 months.

Main Results:

• 121 patients treated beyond 24 hours and 1824 within 6-24 hours.
• Lower functional independence at 90 days for the extended window group (18.8% vs 34.9%, P=0.005).
• Higher 90-day mortality in the extended window group (OR 2.34, P=0.023).
• Similar rates of symptomatic intracerebral hemorrhage and complications between groups.
• Fewer thrombectomy attempts were associated with good outcomes (OR 0.27, P=0.022).

Conclusions:

• Mechanical thrombectomy beyond 24 hours is safe, with comparable complication rates to the standard window.
• While outcomes are worse and mortality higher compared to earlier treatment, selected patients may still benefit.
• Further research into patient selection for extended thrombectomy is warranted.