Credit: Philip Patenall/Macmillan Publishers Limited

Patients with ischaemic stroke can benefit from endovascular thrombectomy >6 h after symptom onset if perfusion imaging indicates the presence of salvageable brain tissue, according to the DEFUSE 3 trial, which was recently published in the New England Journal of Medicine.

Thrombectomy administered within the first 6 h after stroke onset is known to improve patient outcomes. However, many patients — in particular, those who experience a stroke while they are asleep — present to the clinic beyond this time window and are, therefore, ineligible for thrombectomy under the current guidelines.

“We developed a software package called RAPID that could identify salvageable brain tissue,” explains study leader Gregory Albers. “Our pilot studies, DEFUSE 2 and CRISP, showed excellent outcomes when we treated patients with thrombectomy at >6 h if they had a favourable profile on RAPID.”

patients who live far away from a stroke centre now have the prospect of highly effective therapy

DEFUSE 3 included 182 patients who had sustained a proximal middle cerebral artery or internal carotid artery occlusion within the past 6–16 h, and showed evidence of potentially reversible brain ischaemia on perfusion scans analysed by RAPID. The participants were randomly assigned to undergo thrombectomy plus medical therapy, or medical therapy alone.

In this selected patient population, thrombectomy was associated with improved functional outcomes and an increased probability of achieving functional independence. In addition, 90-day mortality was reduced in the group of patients who underwent thrombectomy.

“One-third of strokes occur during sleep; these were previously untreatable, but now they are potentially treatable,” comments Albers. “Also, patients who live far away from a stroke centre now have the prospect of highly effective therapy.”