Extended time window mechanical thrombectomy for pediatric acute ischemic stroke

Abstract

Endovascular thrombectomy (EVT) for the treatment of acute ischemic stroke (AIS) remains an off-label procedure seldom utilized in the pediatric population; this holds especially true for patients presenting outside the standard 6-hour time window. In this review we describe the published literature regarding usage of the extended time window EVT in pediatric stroke. We searched PubMed for all pediatric AIS cases and case series that included patients treated with extended time window EVT. We found data from 38 cases found in 27 publications (15 case reports and 12 case series). The median age was 10 years; 60.5% males. The median NIHSS before EVT was 13 with a median time-to-treatment of 11 hours. The posterior circulation was involved in 50.0%. Stent retrievers were used in 68.5%, and aspiration in 13.2%. Angiographic outcome TICI ≥2B was achieved in 84.2%, whereas TICI˂2B was reported in 10.6%. A favorable clinical outcome (NIHSS score ≤4, modified Rankin score ≤1, or Pediatric Stroke Outcome measure score ≤1) occurred in 84.2%. Eight cases that did not report the clinical outcome employing a standardized scale described mild to absent neurological residual deficits. This study found data that supports that extended window EVT produces high recanalization rates and good clinical outcomes in pediatric patients with AIS. Nevertheless, the source materials are indirect and contain substantial inconsistencies with an increased risk of bias that amount to low evidence strength.

Keywords: Pediatric; endovascular; stroke; thrombectomy.

Figure 1.

Search strategy.

Figure 2.

Illustrative case. A 12-year-old male with Henoch-Schönlein purpura with NIHSS of 13 at 15 hours from onset of symptoms. (A) Diffusion-weighted magnetic resonance imaging shows significant restriction in the territory of the right middle cerebral artery (MCA), absent in the FLAIR sequence (B). Time-of-flight magnetic resonance (TOF-MR) shows distal M1 occlusion. (C) Digital subtraction angiography corroborated the occlusion (arrow) and showed luminal thrombus in the internal carotid artery (white arrowhead). (D) Thrombectomy was performed via a 5F guide catheter with a Trevo 4×20 mm delivered via a Rebar 18 microcatheter, resulting in Thrombolysis in Cerebral Infarction 3 recanalization after one pass at 17 hours from onset of symptoms. (E) 3-month follow-up TOF-MR shows the right MCA (black arrow) with a narrower caliber compared to the left MCA (black arrowhead) (F).