GP’s guide to large vessel occlusion stroke in children

ARTERIAL ischaemic stroke (AIS) is rare in children but can cause marked long term disability. A high index of suspicion from a GP may prevent a lifetime of disability.

Just like in adults, nearly one-quarter of childhood strokes are due to acute blockages in the large arteries supplying the brain – termed large vessel occlusions (LVOs).

Because adults with LVO stroke have such poor outcomes when managed conservatively, neurologists and neuro-interventionists now treat this condition earlier and more aggressively with clot-busting drugs (thrombolysis) and by performing clot retrieval (mechanical thrombectomy).

There has been much debate about whether children with LVO strokes should be treated as aggressively or managed conservatively, in the hope that plasticity and strong collateral vessels would limit the impact of their strokes. The lack of data on the natural history of children with LVO stroke can cause extensive uncertainty for doctors when confronted with a child in this scary situation.

Presentation

Children with AIS can present similarly to adults with stroke (sudden onset of facial weakness, limb weakness, or speech loss) but many also have symptoms not seen that often in adult stroke, such as headache or seizures. In newborns with acute stroke, seizures are often the initial clinical finding. Children’s symptoms may fluctuate in severity such that when they present to your rooms or department they have no detectable deficit. This fluctuation can lead a doctor to underestimate the severity of the situation.

In our recent study published in JAMA Neurology, my colleagues and I found that around half the children with LVO have cardiac disease or arterial dissection; therefore, a history of cardiac disease or trauma should raise a high level of suspicion.

For reasons incompletely understood, childhood AIS is more common in boys than girls. Newborns and teenagers are more commonly affected than other age groups. There are several common clinical mimics in children, such as migraine, epilepsy, Bell’s palsy, conversion disorders, and hypoglycaemia. Children with LVO tend to have more severe clinical syndromes.

Treatment

Early diagnosis is key to obtaining successful treatment. Even a mild suspicion that a child could be having a stroke warrants escalation in clinical management. Using computed tomography or magnetic resonance imaging angiography is very helpful in determining if an LVO is present, but in young children this may require anaesthesia. Paediatric neurologists can help triage children who need urgent imaging versus those who can wait until the next day.

Children found to have an LVO can potentially be offered thrombolysis and/or clot retrieval if they can be recognised early enough and brought to a children’s hospital (here, here, here and here). We don’t have the randomised controlled trial data that are available for adult stroke, but we know that these treatments have been performed successfully hundreds of times in children across the world.

Prognosis and outcomes

We recently demonstrated in a study across New South Wales that children with LVO who did not receive thrombolysis or clot retrieval had markedly worse outcomes (three-quarters had moderate to severe disability or death at 3 months) than those who did (50%) or those whose stroke was not due to LVO (40%). Followed into the long term, these significant differences continued (57% of untreated LVO patients had long term moderate to severe disability v 33% of treated LVO patients). Our study was limited by its retrospective design and the absence of randomisation.

Should we offer thrombolysis and clot retrieval in children?

It helps treating doctors to know that LVO stroke in children will likely have a poor outcome if untreated or treated too late. We don’t have evidence from randomised controlled trials on these treatments in children like we do in adults, and we likely never will. To try and run such a trial in children would not be ethical (given the extensive evidence base in adults) and likely would not succeed due to small numbers and slow recruitment.

With this new data on the poor natural history of LVO stroke in children when left untreated, we can more easily justify offering treatment to children in this situation. Such discussions require us to openly relay to parents the absence of randomised trial data in children and the presence of some uncertainty as to the best thing to do.

But we can at least tell them what the likely outcome will be if untreated and that these treatments have been successfully performed on hundreds of children worldwide.

Future research

The focus into the future is collecting prospective data. Already, there are multiple prospective registries for childhood stroke being formed in Australia and internationally. These registries will allow us to collect data and reduce bias as these treatments are increasingly given to children.

How can GPs help manage children with AIS and LVO stroke?

The greatest advantage a GP has in this situation is their knowledge of the patient and their family. When a child presents with headache and a possible transient neurological deficit, GPs can escalate the situation rapidly by having a strong index of suspicion. A prior history of cardiac disease or trauma is particularly concerning. When confronted with such a situation, a phone call to your nearest paediatric emergency department admitting officer can be very helpful with decisions.

It might be that the child you send to the paediatric emergency department comes back with a diagnosis of migraine. But you may also have prevented a lifetime of disability through your quick action.

One of the most important roles a GP has in the long term is as support to the family. When a child has a stroke, even when successfully treated, the event is very dramatic and can leave long term psychological scars on the whole family. A GP can be there to support that growing child long after the hospital visits have stopped.

Dr Kartik Bhatia is a Paediatric Interventional Neuroradiologist at Sydney Children’s Hospital Network.

The statements or opinions expressed in this article reflect the views of the authors and do not necessarily represent the official policy of the AMA, the MJA or InSight+ unless so stated.

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