Effect of periprocedural antithrombotic medication on functional outcome and symptomatic intracranial hemorrhage in patients with carotid tandem lesions.
In patients with carotid tandem lesions undergoing endovascular treatment, periprocedural antithrombotic therapy was associated with worse functional outcome and a numerically higher rate of symptomatic intracranial hemorrhage, though the sICH association was not statistically significant and estimates were imprecise.
Key Findings
Results
Periprocedural antithrombotic therapy was associated with worse good functional outcome in tandem lesion patients undergoing EVT.
Among 76 patients receiving antithrombotic therapy, 26 (34.2%) achieved good functional outcome (mRS 0-2 at 90 days), versus 14/24 (60.9%) without antithrombotic therapy.
Adjusted OR for good functional outcome with antithrombotic therapy was 0.79 (95% CI 0.63 to 0.99).
Good functional outcome rates by regimen were: 30.4% with aspirin (aOR 0.82, 95% CI 0.61 to 1.11), 29.2% with heparin (aOR 0.75, 95% CI 0.57 to 0.99), and 41.4% with both (aOR 0.81, 95% CI 0.62 to 1.06).
This was a post-hoc analysis of the MR CLEAN-MED randomised multicentre clinical trial (ISRCTN76741621), enrolling patients between 22 January 2018 and 27 January 2021.
Results
Symptomatic intracranial hemorrhage occurred at a numerically higher rate in antithrombotic-treated tandem lesion patients, though the association was not statistically significant.
sICH occurred in 15.8% of antithrombotic-treated patients versus 4.4% without antithrombotic therapy.
The unadjusted OR for sICH with antithrombotic therapy was 4.31 (95% CI 0.53 to 35.02), which did not reach statistical significance.
The wide confidence interval indicates the estimate was imprecise.
sICH was classified according to the Heidelberg criteria.
sICH rates by regimen were: 17.4% with aspirin, 16.7% with heparin, and 13.8% with both aspirin and heparin.
Methods
Carotid tandem lesions were present in 100 of 628 patients enrolled in the MR CLEAN-MED trial.
628 total patients were included in the MR CLEAN-MED trial between 22 January 2018 and 27 January 2021.
100 patients (approximately 15.9%) had a tandem lesion, consistent with the stated prevalence of up to 15% in the eligible EVT population.
Tandem lesion was defined as extracranial carotid artery stenosis of ≥50% or occlusion with an intracranial large vessel occlusion of atherosclerotic origin.
76 of the 100 tandem lesion patients received periprocedural antithrombotic therapy and 24 did not.
Methods
Antithrombotic regimens studied included aspirin alone, heparin alone, and both aspirin and heparin combined.
The analysis compared outcomes across three active antithrombotic regimens and a no-antithrombotic comparator group.
Outcomes were compared using logistic regression adjusted for baseline variables.
Good functional outcome was defined as modified Rankin Scale score of 0–2 at 90 days.
The MR CLEAN-MED trial was a randomised multicentre clinical trial evaluating periprocedural antithrombotic management in EVT patients.
What This Means
This research examined how blood-thinning medications given during or around a procedure to remove a clot from a brain artery (endovascular treatment) affect outcomes in stroke patients who have a specific condition called a carotid tandem lesion — where both a neck artery and a brain artery are blocked or severely narrowed at the same time. Using data from a large randomized clinical trial (MR CLEAN-MED), the researchers analyzed 100 such patients and compared those who received blood thinners (aspirin, heparin, or both) to those who did not.
The study found that patients who received blood-thinning medications were less likely to have a good recovery (being able to function independently at 90 days) compared to those who did not receive these medications — about 34% versus 61% achieved good outcomes. Additionally, bleeding inside the skull (a serious complication) occurred more often in treated patients (15.8%) than in untreated patients (4.4%), though this difference was not statistically conclusive due to the small number of patients and wide uncertainty in the estimates. No single blood-thinner regimen clearly outperformed the others.
This research suggests that routinely giving blood-thinning medications to tandem lesion patients during clot-removal procedures may not improve — and could potentially worsen — outcomes, but the small sample size means these findings should be interpreted cautiously. Larger, dedicated studies are needed to determine the safest and most effective approach to managing blood thinners in this challenging patient group.
van Elk T, Vogt R, Maes L, van der Meij A, Wermer M, van der Steen W, et al.. (2026). Effect of periprocedural antithrombotic medication on functional outcome and symptomatic intracranial hemorrhage in patients with carotid tandem lesions.. BMJ open. https://doi.org/10.1136/bmjopen-2026-119120