Following a stroke, the time frame for effective treatment is key, as prolonged blockage of blood flow to the brain can lead to permanent damage or death. A procedure known as endovascular thrombectomy, which involves the physical removal of the clot to restore circulation, has been shown to significantly reduce long-term disability or death. Typically, this emergency treatment is administered within the first 24 hours after a stroke occurs.
Expanding Treatment Options
Researchers recently conducted a study to determine whether thrombectomy could be beneficial for patients beyond the initial 24-hour window. The study examined whether brain scans could identify areas of the brain that, despite being deprived of oxygen and blood, had not yet suffered irreversible damage. The LATE-MT trial involved adult patients from 35 stroke centers in China who had experienced an ischemic stroke due to a blocked major blood vessel. Patients were divided into two groups: one underwent mechanical thrombectomy between 24 and 72 hours after symptoms began, in addition to receiving medication, while the other group received only standard stroke medications.
The results of the study showed that patients who underwent thrombectomy experienced significantly better overall functional recovery. At the 90-day mark, approximately 49% of treated patients were able to live independently, compared to 35% of those who received medication alone. The study’s findings are published in the New England Journal of Medicine and are based on a prospective, randomized controlled trial involving 336 eligible patients from stroke centers across China, divided into two equal groups of 168. The control group received standard care, including oral antiplatelet drugs, treatment for brain swelling, and routine hospital support, while the other group underwent mechanical thrombectomy alongside guideline-based medical care, with the procedure aiming to start within 60 minutes of randomization.
Weighing the Benefits and Risks
At the 90-day mark, patients who underwent thrombectomy demonstrated better recovery outcomes, as reflected in their modified Rankin Scale scores, which measure the extent of disability after a stroke. Among patients who underwent thrombectomy, 26.9% had no significant disability, despite some remaining symptoms, compared to 15.6% in the control group. These patients also reported improved quality of life and greater ability to manage daily activities. However, the benefits of thrombectomy came with increased risks, including symptomatic intracranial hemorrhage, which occurred in 4.8% of patients who underwent the procedure, compared to none in the control group. The 90-day death rate was also higher among patients who received thrombectomy, at 6.0% compared to 1.8%.
Specialists should carefully assess whether selected patients may still benefit from thrombectomy, taking into account the amount of salvageable brain tissue post-stroke and the potential risks associated with the procedure. The study’s findings suggest that the 24-hour mark is no longer the definitive deadline for thrombectomy, and patients who arrive at the hospital more than 24 hours after a stroke should not be automatically excluded from consideration for the procedure.
As stated by the researchers, “patients arriving more than 24 hours after a stroke should not automatically be ruled out for thrombectomy.” The study’s results are published in the New England Journal of Medicine by Pengfei Yang et al., “Mechanical Thrombectomy 24 to 72 Hours after Large-Vessel Ischemic Stroke” (2026).