# Comparison between single and dual antiplatelet therapy in patients on oral anticoagulants undergoing coil embolization for unruptured intracranial aneurysms: a retrospective multicenter cohort study

## TL;DR

This study compares single and dual antiplatelet therapy in patients on blood thinners undergoing a brain aneurysm procedure, finding no benefit in reducing blood clots but increased bleeding risks with dual therapy.

## Contribution

The study provides new evidence on the safety and efficacy of antiplatelet strategies in a specific high-risk patient group undergoing coil embolization.

## Key findings

- Dual antiplatelet therapy did not reduce thromboembolic events compared to single antiplatelet therapy.
- Dual antiplatelet therapy was associated with significantly higher bleeding events compared to single antiplatelet therapy.

## Abstract

The optimal antiplatelet therapy for patients on continuous oral anticoagulants (OACs) who are undergoing coil embolization for unruptured intracranial aneurysms (UIAs) is remains unknown. This study evaluated the efficacy and safety of single- (SAPT) and dual antiplatelet therapy (DAPT) in patients taking OACs who underwent coil embolization for UIAs.

This retrospective multicenter study included patients taking OACs who underwent coil embolization for UIAs at 9 hospitals between January 2016 and August 2023. The primary outcome was a thromboembolic complication within 30 days post-procedure. The secondary outcome was a composite all bleeding events according to the Thrombolysis in Myocardial Infarction bleeding criteria.

A total of 112 patients (mean [standard deviation] age, 67.3 [9.7]; 67 females [59.8%]) were included. Among them, 31 patients (27.7%) received SAPT, and 81 patients (72.3%) received DAPT. There was no significant difference in the thromboembolic event rate between the 2 groups (SAPT group: 2 of 31 [6.5%]; DAPT group: 3 of 81 [3.7%]; unadjusted hazard ratio [HR], 0.55 [95% CI, 0.09–3.30]; P = .52). However, the rate of all bleeding events after coil embolization in the DAPT group was significantly higher than that in the SAPT group (SAPT group: 2 of 31 [6.5%]; DAPT group: 22 of 81 [27.2%]; adjusted HR, 5.57 [95% CI, 1.30-23.83]; P = .02).

With respect to SAPT, DAPT was not associated with a reduction in thromboembolic complications in patients taking OACs who underwent coil embolization, but it was associated with an increase in all bleeding events.

The online version contains supplementary material available at 10.1007/s00234-025-03844-2.