Adjusting Antiplatelet Therapy Using P2Y₁₂ Reaction Units in Endovascular Treatment of Unruptured Intracranial...

The effectiveness of platelet reactivity unit (PRU)-guided individualized antiplatelet therapy for intracranial aneurysm treatment remains uncertain.

This retrospective study evaluated 1705 patients with 1883 unruptured intracranial aneurysms who received endovascular treatments at a tertiary center between March 2018 and December 2020. Patients were divided into 2 groups: a standard group (aspirin and clopidogrel without PRU) and an individualized group where antiplatelet therapy was adjusted or switched to low-dose prasugrel based on preprocedural PRU values by VerifyNow. In the individualized group, hyporesponsiveness was defined as PRU>238 or inhibition <26%, prompting transition to low-dose prasugrel, whereas hyperresponsiveness was defined as PRU<86 or inhibition >74%, leading to dose withholding. The primary outcome was thromboembolic and hemorrhagic complications within 1 month. Thromboembolic complications included intraprocedural thrombosis, transient ischemic attack, and ischemic stroke confirmed on diffusion-weighted imaging; microembolism was defined as acute diffusion-weighted imaging lesions <1 cm. Hemorrhagic complications encompassed intracranial bleeding and extracranial access site hematomas (retroperitoneal hematoma, puncture-site pseudoaneurysm). Functional outcomes were assessed using the modified Rankin Scale. Subgroup analyses were performed for complex procedures, defined as stent-assisted coiling and flow diversion.

Average patient age was 58.0±10.8 years; 72.4% were female. The cohort included 1020 patients in the standard group and 685 in the individualized group. No significant difference in overall thromboembolic complications was observed between the standard (2.4%) and individualized groups (1.3%; P=0.127). However, individualized therapy significantly reduced thromboembolic events in complex procedures, including stent-assisted embolization and flow diversion (3.3% versus 1.0%; P=0.017; P for interaction=0.049). In the flow diverter subgroup, the incidence of microembolism was significantly lower in the individualized group (47.8% versus 26.8%; P=0.049). Hemorrhagic complication rates were similar between groups.

Individualized antiplatelet therapy based on PRU measurements did not impact overall outcomes but reduced ischemic complications in complex endovascular treatments without increasing bleeding risks. Further validation is necessary.