Introduction It is generally believed that antiplatelet effect, especially clopidogrel, reaches and maintain a therapeutic range and plateau within 5–7 days. However, the consistence of clopidogrel effect after stent-assisted coil embolization is unclear.

Aim of Study The purpose of this study was to evaluate follow-up P2Y12 reaction unit (PRU) in the patients who underwent stent-assisted coil embolization.

Methods The Patients were administered a dual antiplatelet (100mg of aspirin and 75mg of clopidogrel) for 5 days prior to coil embolization. The follow-up PRU was evaluated between 2 and 4 weeks after stent-assisted coil embolization in the outpatient clinic. To evaluate the predictability of significant variables for a follow-up PRU value less than 80, the receiver-operating characteristic (ROC) curve method was employed. The optimal cutoff value was determined using the Youden index.

Results A total of 124 patients with 131 aneurysms were included in this study. The median PRU before coil embolization was 155 (IQR 124–181), and the median follow-up PRU after coil embolization was 142 (IQR 92–179). A total of 29 patients (23.4%) had a follow-up PRU value less than 80. The optimal cut-off value of pre-procedural PRU to predict a follow-up PRU value less than 80 was 124.

Conclusion The PRU level after stent-assisted coil embolization can decrease to a hyper-response level despite an acceptable range of the PRU Before Procedure. The significant predictor of hyper-response was the pre-procedural PRU level. The optimal cut-off value of pre-procedural PRU to predict a follow-up PRU value less than 80 was 124.

Disclosure of Interest Nothing to disclose