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Published on: September 17, 2014
"Mechanical thrombectomy beyond 6 hours for acute ischemic strokes due to M2 occlusions"
Maria Pereira Coutinho1, Sofia Galego2, Marta Alves3
1Neurology Department, Unidade Local de Saúde de São José, Lisbon, Portugal.
Background:
The time frame for mechanical thrombectomy (MT) in acute ischemic stroke (AIS) is enlarging. Guidelines recommend MT until 6 h of symptom onset in M2 segment occlusions (grade IIB). In practice, it is frequently performed later.
Aims:
To assess the functional prognosis of AIS patients subjected to M2 segment's MT beyond 6 h, compared to standard intervention.
Methods:
Retrospective cohort study including all consecutive AIS patients subjected to MT of M2 occlusions between 1st January 2018 and 31st December 2020 in St Joseph's Local Health Unit, Lisbon, Portugal. Allocation to standard or extended groups was done according to the symptom-to-puncture time, whether within or beyond 6 h after symptom onset, respectively. The primary outcome was the modified Rankin Scale (mRS) at three months. Secondary outcomes were symptomatic intracranial hemorrhage (sICH) at 24 h and three-month mortality.
Results:
We included 155 patients, 51.0 % men, median age 76.0 years (P25:69.0;P75:86.0), baseline mRS "0-2" in 84.5 %, mean NIHSS 13.6(6.5). Initial Computed Tomography showed early ischemic changes in 27.1 %. Most patients belonged to the standard group (71.0 %). Groups had similar baseline features. The standard group underwent more frequent (68.2 % vs 44.4 %, p = 0.006) and earlier (2 h02 min, 3 h02 min, p < 0.001) fibrinolysis. Symptom-to-puncture times were 7 h13 min (extended) and 4h01 min (standard), p < 0.001. Outcomes were similar between groups (three months' mRS [p = 0.578]; sICH [p = 0.720]; three-month mortality [p = 0.422]).
Conclusions:
Our study suggests similar outcomes in M2 occlusions performing MT before and beyond 6 h of symptom onset, consistent with previous studies. Patients might benefit from widening inclusion criteria for MT in AIS.
Insights
Mechanical thrombectomy (MT) for acute ischemic stroke (AIS) in M2 occlusions shows similar outcomes whether performed within or beyond 6 hours. Expanding treatment windows for MT may benefit more patients with AIS.
Area of Science:
- Neurology
- Interventional Neuroradiology
- Stroke Medicine
Background:
- Mechanical thrombectomy (MT) guidelines for acute ischemic stroke (AIS) typically recommend intervention within 6 hours of symptom onset for M2 segment occlusions.
- However, MT is often performed later in clinical practice.
Purpose of the Study:
- To evaluate the functional outcomes of AIS patients undergoing MT for M2 occlusions beyond the 6-hour window compared to those treated within the standard timeframe.
- To assess secondary outcomes including symptomatic intracranial hemorrhage and mortality.
Main Methods:
- A retrospective cohort study was conducted on AIS patients who underwent MT for M2 occlusions between January 2018 and December 2020.
- Patients were divided into standard (≤6 hours) and extended (>6 hours) groups based on symptom-to-puncture time.
- The primary outcome was the modified Rankin Scale (mRS) at three months, with secondary outcomes being symptomatic intracranial hemorrhage (sICH) and three-month mortality.
Main Results:
- The study included 155 patients, with similar baseline characteristics between the standard and extended groups.
- While the standard group received more frequent and earlier fibrinolysis, symptom-to-puncture times differed significantly (4h01min vs 7h13min).
- No significant differences were observed in three-month mRS scores, sICH rates, or three-month mortality between the groups.
Conclusions:
- Mechanical thrombectomy for M2 occlusions demonstrates comparable functional outcomes and safety profiles when performed within or beyond the 6-hour time window.
- These findings support the potential benefit of widening inclusion criteria for MT in AIS patients.
- Further research may confirm the efficacy of extended MT treatment windows.
