Stroke treatment improves patients’ chances of avoiding brain damage

People who suffer a severe stroke could soon be twice as likely to avoid serious brain damage and return to living independently, thanks to Australian-led research set to change treatment standards around the world.

Researchers at Royal Melbourne hospital combined a new minimally invasive clot-removal procedure with the standard treatment for stroke, which involves administering a clot-dissolving drug.

They recruited 70 patients across 14 hospitals in Australia and New Zealand, and gave half the combined therapy. All had suffered an ischaemic stroke, the most common form of stroke, caused by a blood clot blocking a blood vessel to the brain.

Blood flow to the brain was restored in 89% of patients who received both treatments, compared with 34% of those who received the drug alone. After three months, 71% of patients who received both treatments returned to independent living, compared with 40% in the drug treatment group.

Professor Peter Mitchell, a neurointerventionalist involved with the study, said the standard intravenous drug was the only stroke treatment that currently existed.

It was most effective for dissolving small blood clots, he said, and there were restrictions around which patients were most eligible to receive it and when.

“Not only does the drug not break large clots down very well, it takes a long time to circulate through the system and get to the brain to start working on those clots and be effective,” he said.

“The longer you wait to restore oxygen to the brain, the more brain damage there is, with patients losing about two million neurons per minute until oxygen is restored.”

Doctors decided to try using a stent device traditionally inserted into the brain of aneurysm patients to see if it could be used to drag large blood clots out of the body after a stroke.

They found the brain stent was flexible enough to stretch and open up a blood vessel, while also strong enough to hold on to and remove a blood clot.

The procedure involves making a nick in the femoral artery near the groin, then feeding the stent up to the clot where it is captured and dragged out through the artery. It takes an average of 43 minutes, and is most effective when performed on patients who are still awake but given a local anaesthetic, Mitchell said.

Images were taken of the brains of patients before surgery to identify which parts of the brain were already dead and which were worth saving, so the surgery could be targeted to those clots.

While the intravenous drug treatment would likely remain best practice for small clots, Mitchell said the combined drug and stent therapy would become standard treatment for more severe strokes.

“This will give them almost twice the chance of having a good recovery,” he said.

“I imagine it will be rolled out in hospitals that have specialist stroke treatment centres and will then be more widely available in other hospitals within five years.”

The findings were presented at the International Stroke Conference in the US, and published in the New England Journal of Medicine on Thursday.

Stroke is the leading cause of disability in adults and the number two cause of death worldwide.

The National Stroke Foundation’s chief executive, Dr Erin Lalor, said the new treatment could save thousands of Australians from death and severe disability.

She said the findings must now be considered for incorporation into national stroke treatment clinical guidelines.

“The development of new stroke clinical guidelines will provide certainty and support for stroke clinicians to deliver the most up-to-date evidence-based stroke care for their patients,” she said.

Leave a Comment