Antiplatelet Therapy in Endovascular Treatment of Cerebral Aneurysm

• Fulminant simultaneous multiple dissections of the cervical and vertebral arteries leading to hemorrhagic and ischemic stroke: A case report
• Early experience using optical coherence tomography for intraluminal evaluation of vascular healing associated with endovascular treatment of intracranial aneurysms
• The Transradial Approach for Endovascular Treatment of Vasospasm
• Comparative analysis between stent-assisted coiling and Woven EndoBridge embolization for unruptured wide-necked bifurcation intracranial aneurysms: A propensity score matching study
• Full dose of cangrelor in the acute treatment of small ruptured cerebral aneurysms with flow diverters: a single center experience
• Evaluation of acute intraprocedural thromboembolism risk factors in endovascular treatment of unruptured intracranial aneurysms
• Guided Antiplatelet Therapy for Stent-Treated Intracranial Aneurysms: A Cluster-Randomized Trial
• Y-stent-assisted coiling for large wide-neck dysplastic middle cerebral artery bifurcation aneurysm: An update to procedural technique

Endovascular treatment of cerebral aneurysms, including coil embolization, stent-assisted coiling, and flow-diverting stents, necessitates careful management of antiplatelet therapy to prevent thromboembolism and hemorrhagic complications. The choice of antiplatelet regimen depends on the device used, patient-specific factors, and the balance between thrombosis and bleeding risks.

Endovascular treatments involve the placement of foreign materials (coils, stents, or flow diverters) that can trigger platelet aggregation and thrombus formation. Antiplatelet therapy mitigates this risk by inhibiting platelet activation and aggregation.

Dual Antiplatelet Therapy (DAPT): Standard regimen for stent-assisted coiling and flow diverter placement.

Single Antiplatelet Therapy (SAPT): Occasionally used for simple coiling procedures.

Aspirin (ASA)

Irreversible Cyclooxygenase-1 inhibitor that reduces thromboxane A2-mediated platelet activation.

Dose: 75-325 mg daily.

Used in combination with P2Y12 inhibitors for stent or flow diverter implantation.

P2Y12 Inhibitors

Inhibit ADP-mediated platelet activation. Common agents: Clopidogrel: Prodrug requiring hepatic activation; response variability due to CYP2C19 polymorphisms. Prasugrel: More potent than clopidogrel, but with higher bleeding risk. Ticagrelor: Direct-acting reversible inhibitor with faster onset and more predictable effect.

Pre-Treatment:

DAPT (Aspirin + Clopidogrel/Prasugrel/Ticagrelor) initiated 3-7 days before stent placement.

Verify platelet inhibition using P2Y12 assays to adjust therapy in hyporesponders.

Intraprocedural:

IV Glycoprotein IIb/IIIa inhibitors (e.g., tirofiban, abciximab) in cases of acute thrombosis.

Post-Procedure:

DAPT continued for 3-12 months depending on the device used.

Transition to SAPT (typically aspirin) for long-term therapy.

Aneurysmal Subarachnoid Hemorrhage (aSAH)

Antiplatelets increase rebleeding risk; limited use unless a stent/flow diverter is necessary. Bridging therapy with IV agents may be required in emergent situations. Platelet Function Testing

Identifies poor responders to clopidogrel, allowing for alternative therapy (prasugrel or ticagrelor). Bleeding Risks

Higher with prasugrel/ticagrelor than with clopidogrel. Dual antiplatelet therapy should be tailored to individual risk profiles.

Antiplatelet therapy is crucial in endovascular treatment of cerebral aneurysms to reduce thromboembolic complications. A tailored approach, incorporating platelet function testing and patient-specific risk assessment, optimizes outcomes while minimizing bleeding complications.

Thromboembolism is one of the main causes of severe complications in the endovascular treatment of cerebral aneurysms, and antiplatelet therapy (APT) is necessary to prevent such complications. Conversely, prolonged antiplatelet therapy has the potential risk of hemorrhagic complications; therefore, the timing of dose reduction or antiplatelet therapy discontinuation is an important aspect of periprocedural APT. However, no clinical evidence of an optimal regimen of APT for cerebral aneurysms exists, and the selection, dosage, duration, or combination of antiplatelets has been dependent on physicians for unruptured or ruptured cerebral aneurysms. Many reports have shown that preoperative APT can reduce ischemic complications without increasing hemorrhagic complications, and some reports have shown that the P2Y12 reaction units (PRU) value measured using the VerifyNow (Werfen, Barcelona, Spain) system is associated with periprocedural ischemic and hemorrhagic complications. Appropriate dose and duration management adjustments based on the platelet reactivity testing, aneurysm morphology, treatment, and patient background may contribute to good outcomes. Although accumulating evidence exists regarding the efficacy of preoperative APT, there is no evidence regarding the optimal duration or discontinuation of APT ¹⁾

Matsubara et al. effectively highlight the importance of APT for thromboembolism prevention in neuroendovascular procedures. However, the study lacks specific guidelines on antiplatelet therapy discontinuation, standard PRU cutoffs, and alternative antiplatelet regimens. While the evidence supporting preoperative APT is growing, future research should focus on RCTs that establish optimal treatment durations and risk stratification models to ensure safe and effective therapy.