A study coordinated by Hospital Clínic Barcelona and IDIBAPS, published in JAMA, shows that administering a thrombolytic drug directly into the cerebral artery after mechanical thrombectomy significantly improves functional recovery in patients with severe ischemic stroke.
The study, known as CHOICE2, follows on from previous research published in 2022 by the same research team and reinforces the idea that, in some patients, reopening the main artery is not sufficient to ensure good brain recovery.
The study was coordinated by Ángel Chamorro, head of the Cerebrovascular Diseases Unit at Hospital Clínic and member of the IDIBAPS Cerebrovascular Diseases research group, who presented preliminary results at the plenary session of the International Stroke Conference in New Orleans last February. The first author of the study and coordinator of the trial at Hospital Clínic was Dr. Arturo Renú, from the same team.
What is ischemic stroke and how is it usually treated?
Ischemic stroke occurs when a blood clot blocks an artery in the brain, preventing blood and oxygen from reaching brain tissue. When stroke affects a large artery, the standard treatment is mechanical thrombectomy, a minimally invasive procedure that removes the clot and restores blood flow.
This treatment has represented a major advance in the care of severe stroke. However, a significant proportion of patients do not fully recover their independence, even when the procedure is technically successful.
“With thrombectomy we can reopen the blocked artery, but that does not always guarantee that blood reaches all areas of the brain properly,” explains Arturo Renú.
Why going beyond thrombectomy is necessary
Several studies have shown that after removal of the main clot, impaired circulation may persist in the brain’s smaller vessels, a condition that can limit neurological recovery.
“This is what we call a microcirculation problem,” explains Chamorro. “It is like reopening a highway while some side streets remain blocked. If blood does not reach brain tissue properly, the brain cannot fully recover.”
This was the basis of the CHOICE study, published in 2022 in JAMA, which already suggested that adding a pharmacological treatment after thrombectomy could help improve this fine cerebral circulation.
What does the CHOICE‑2 study add?
The CHOICE2 trial confirmed this hypothesis in a larger sample. The study included 440 adult patients with severe ischemic stroke treated at 14 specialized hospitals in Spain.
All patients were successfully treated with mechanical thrombectomy. They were then randomly assigned to two groups:
one group received standard treatment only,
and the other received, immediately after the procedure, a thrombolytic drug, a medication that helps dissolve small clots and improve blood circulation in the brain.
This treatment is administered in a targeted manner during the same procedure, with the aim of improving blood flow to affected brain areas.
Better functional recovery at 90 days
Results show that patients treated with this combined strategy had better outcomes. Ninety days after stroke, 57.5% of patients who received the additional treatment achieved very good functional recovery—without disability or with minimal symptoms—compared with 42.5% of patients treated with thrombectomy alone.
Imaging tests also showed that these patients had fewer brain areas with insufficient blood flow, a key factor for neurological recovery.
“Improving circulation in the brain’s smallest vessels can make a significant difference in patient outcomes,” says Arturo Renú.
A consolidated line of research
The CHOICE2 study expands and consolidates the results observed in the CHOICE trial published in 2022, which had already pointed to the benefits of this strategy but involved fewer participants.
“We now have stronger evidence that helps us better understand why some patients do not recover as well as expected after thrombectomy,” highlights Ángel Chamorro. “This knowledge is key to continuing to move towards more personalized treatments.”
Researchers note that the additional treatment did not significantly increase the risk of serious complications and emphasize the importance of continuing research to better define which patients may benefit most.
Research with international impact
This research consolidates the role of Hospital Clínic‑IDIBAPS as international reference centers in stroke research and treatment, with the aim of translating scientific advances into better patient care.
According to Chamorro, “the accumulated evidence from the CHOICE and CHOICE‑2 studies will lead to a paradigm shift in the treatment of ischemic stroke and will change therapeutic guidelines regarding thrombectomy.” The thrombolytic drug, previously administered before the procedure, will now be given afterwards, as this approach is more effective in eliminating smaller clots.
The study was funded by the Instituto de Salud Carlos III and the European Union, through the Next Generation EU program, within the framework of the Recovery, Transformation and Resilience Plan.
Study reference:
Renú A, Fernández-Couto MD, de la Riva P, et al. Adjunctive Intra-Arterial Alteplase After Successful Thrombectomy for Acute Ischemic Stroke: The CHOICE-2 Randomized Clinical Trial. JAMA. Published online May 07, 2026. doi:10.1001/jama.2026.5164
