Selective intra-arterial hypothermia during mechanical thrombectomy was not associated with a significant improvement in hypoperfused tissue salvage volume, the prespecified primary endpoint, though nominally favorable secondary clinical signals require confirmation in larger randomized trials.
Key Findings
Results
Hypoperfused tissue salvage volume did not differ significantly between the hypothermia and standard-treatment groups.
Median hypoperfused tissue salvage volume was 107.85 mL (IQR, 53.80–159.64) in the hypothermia group versus 81.96 mL (IQR, 50.23–143.80) in the standard-treatment group.
The difference was not statistically significant (p = 0.384).
In adjusted median regression, hypothermia was not significantly associated with tissue salvage volume (adjusted median difference, 21.08 mL; 95% CI, −23.47 to 65.63; p = 0.350).
The study included 94 patients: 45 in the hypothermia group and 49 in the standard-treatment group.
Results
Final infarct volume did not differ significantly between the hypothermia and standard-treatment groups.
Final infarct volume was assessed on follow-up MRI.
No statistically significant difference was found between the two groups.
This was a secondary outcome analyzed descriptively without formal adjustment for multiple comparisons.
Results
Day-7 NIHSS improvement was nominally greater in the hypothermia group compared to the standard-treatment group.
Mean day-7 NIHSS improvement was 6.2 ± 5.9 in the hypothermia group versus 3.8 ± 5.7 in the standard-treatment group (p = 0.043).
This was a descriptive secondary analysis without formal adjustment for multiple comparisons.
The authors characterized this as a nominal finding to be interpreted as exploratory.
Results
A higher proportion of patients in the hypothermia group achieved 90-day functional independence compared to the standard-treatment group.
Functional independence at 90 days was achieved by 82.2% of patients in the hypothermia group versus 61.2% in the standard-treatment group (p = 0.039).
This was a descriptive secondary outcome analyzed without formal adjustment for multiple comparisons.
The authors characterized this as a nominally favorable signal requiring confirmation in larger randomized trials.
Results
Safety outcomes did not differ significantly between the hypothermia and standard-treatment groups.
No statistically significant differences in safety outcomes were observed between groups.
The study was a prospective single-center nonrandomized comparative cohort study.
Treatment assignment was at the discretion of the treating interventionist after informed consent.
Methods
The study design was a prospective single-center nonrandomized comparative cohort study enrolling consecutive patients with anterior-circulation large-vessel occlusion treated with mechanical thrombectomy.
94 total patients were included: 45 in the hypothermia group and 49 in the standard-treatment group.
Patients received selective intra-arterial hypothermia or standard treatment at the discretion of the treating interventionist after informed consent.
The primary endpoint was hypoperfused tissue salvage volume, defined as baseline hypoperfusion volume on CT perfusion minus final infarct volume on follow-up MRI.
Secondary outcomes were analyzed descriptively without formal adjustment for multiple comparisons.
What This Means
This research studied whether cooling the brain locally — by delivering cold fluid directly into the blocked artery during a clot-removal procedure (mechanical thrombectomy) — could save more brain tissue in stroke patients. The study enrolled 94 patients with major strokes caused by blocked arteries in the front part of the brain. Researchers compared patients who received this selective intra-arterial hypothermia treatment to those who received standard care, measuring how much brain tissue that was initially at risk (but not yet dead) was ultimately preserved.
The study found that the main outcome — the volume of at-risk brain tissue that was saved — was not statistically different between the two groups. Patients receiving hypothermia saved a median of about 108 mL of tissue compared to about 82 mL in the standard-treatment group, but this difference could have occurred by chance. However, some secondary measures showed nominally better results in the hypothermia group: patients in that group showed greater neurological improvement by day 7, and a higher proportion (82% vs. 61%) achieved functional independence at 90 days.
This research suggests that selective intra-arterial hypothermia during stroke treatment may have some clinical benefits, but the primary imaging-based measure of brain tissue salvage did not show a significant advantage. The authors caution that the promising secondary findings are exploratory and could reflect chance or bias in this non-randomized study. Larger, properly randomized clinical trials are needed to determine whether this cooling approach truly benefits stroke patients.
Bi Q, Wang Y, Fu W, Wang Q, Yang W, Gu J, et al.. (2026). Hypoperfused tissue salvage after selective intra-arterial hypothermia during mechanical thrombectomy for anterior circulation large-vessel occlusion.. Frontiers in neurology. https://doi.org/10.3389/fneur.2026.1890819