The poor natural history of large vessel occlusion (LVO) stroke in children in Australia has added to the growing impetus for endovascular therapy (EVT) in paediatric patients, a group that had been excluded from the country’s landmark thrombectomy trials.
From 2010 to 2019 in New South Wales, Australia, the 26 children who did not receive EVT for LVO stroke more often than not suffered poor functional outcomes at three months, when 73,1% of them had moderate to severe disability according to the paediatric modified Rankin scale (mRS), said Dr Kartik Bhatia, a paediatric neuro-interventionalist at Sydney Children’s Hospital Network.
Compared with 13 peers who did get EVT, this untreated group had worse outcomes at both three months and at six months, Bhatia told the audience at the American Stroke Association’s International Stroke Conference, held both virtually and in New Orleans this year.
Given more time and rehabilitation, rpaediatric LVO stroke patients who underwent thrombectomy fared nearly as well at last mRS assessment as 122 children with non-LVO strokes in the study.
“I think with such poor outcomes [for the untreated LVO group], we should definitely strongly consider thrombectomy for paediatric patients,” Bhatia said. “We should strengthen existing stroke treatment guidelines in children.”
He noted that historic beliefs have hindered the uptake of EVT in children. For instance, the perception that they present too late for thrombectomy isn’t supported by the study, he said, highlighting the finding that 69% of the LVO group showed up within six hours of stroke onset and 21% between six and 24 hours.
Dr Tudor Jovin of Cooper Medical School of Rowan University in Camden, New Jersey, told MedPage Today that he’d thought age would be an important determinant of LVO stroke outcomes, given that younger patients should have better collaterals and better plasticity than adults.
That the natural history is “not that much different” between kids and adults is a “huge insight” from this study, he commented. “We’re not even looking at cognitive implications and other things that are obviously important in the development of children.”
The retrospective study left room for confounding and bias. Given the proven benefits of EVT in adults, however, running a paediatric randomised trial would be neither ethical nor feasible, Bhatia said, while Jovin agreed it would be “difficult” to generate randomised data in this setting. “This is as good as it gets,” he said, noting that there are already centres that treat paediatric and adult stroke patients alike with EVT.
Bhatia said that New South Wales now has a referral pathway for paediatric thrombectomy, and he predicted the regional care network being “more solidified” in the next 5-10 years.
“We should make greater efforts to triage and image children with LVO earlier … We as doctors are not getting them through the hospital and sending them to the thrombectomy suite in time,” he said.
For the state-wide population-based study, study authors pooled all ischaemic stroke admissions in people under 17 at four centres (three paediatric hospitals plus one adult hospital treating older adolescents). The study captured periods both before and after introduction of stroke thrombectomy in adults.
Paediatric stroke patients were about six years old, with LVO patients a few years older than non-LVO peers (median 8 vs 4 years, P=0.007). Boys similarly constituted the majority of both groups (59.0% vs 67.2%, P=0.347).
Bhatia reported that 82% of childrens with LVO strokes would have met criteria for the adult thrombectomy trials except for age.
Study details
Paediatric Large Vessel Occlusion Stroke: Poor Outcomes Without Intervention
Kartik Bhatia, Romain Briest, Robert Goetti, Richard Webster, Chris Troedson, Russell C Dale, Ferdi Miteff, Prakash Muthusami, Christina Miteff, John worthington, Kylie Tastula, Timothy Ang, Ian Andrews
Presented at virtual International Stroke Conference on 11 February 2020
Introduction
Mechanical thrombectomy has revolutionised the management of large vessel occlusion (LVO) stroke in adults. However, none of the major trials supporting its use included paediatric patients. Major barriers to uptake in children include the retrospective single-arm evidence base, differences in stroke aetiology, and little is reported on the natural history of LVO stroke in children. We aimed to identify the incidence and natural history of LVO stroke in children.
Methods
We undertook a multi-centre statewide retrospective cohort study of all arterial ischaemic stroke (AIS) admissions in patients of age 1 month to <17 years between 2010-2019 across New South Wales, Australia. Statewide incidences of paediatric AIS and LVO were calculated. The primary outcome was paediatric modified Rankin Scale (ped-mRS) score three months after stroke, using ordinal logistic regression to compare non-LVO, LVO without thrombectomy, and LVO with thrombectomy groups.
Results
Of 166 AIS admissions, 39 (23.5%) had LVO, of which 13 received thrombectomy and 26 did not. LVO without thrombectomy patients had significantly worse clinical outcomes than non-LVO patients at three months (OR 3.64, 95%CI 1.68-7.87; p=0.001). Long-term outcomes in LVO patients without thrombectomy were also significantly worse than LVO with thrombectomy (OR 6.07, 95%CI 1.55-23.73; p=0.010). The majority of LVO patients presented within time windows suitable for thrombectomy (27/39, 69.2% <6h; 35/39, 89.7% <24h). Of 39 LVO patients, 32 (82.1%) fulfilled existing adult selection criteria for thrombectomy, other than age.
Conclusions
The natural history of paediatric LVO stroke with conservative management is poor. The majority suffer long-term moderate to severe disability or death. Outcomes are significantly worse than for non-LVO patients or LVO with thrombectomy patients. Four out of five LVO patients fulfilled adult thrombectomy selection criteria other than age.
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