Utility of platelet function testing in stent-assisted coiling of cerebral aneurysms

Thromboembolic complications are the primary risks of stent-coiling of cerebral aneurysms. The utility of platelet function testing in stent-assisted aneurysm coiling remains controversial. This study aimed to assess a pharmacy-mediated antiplatelet management protocol for stent-assisted coiling.

Stent-coiled aneurysms at an academic institution in the United States between 2015 and 2018 were retrospectively reviewed. All patients were managed using a pharmacy-mediated antiplatelet protocol, which required repeated platelet function testing and subsequent dose adjustments. Medication dosage, number of adjustments, aspirin reaction units (ARU) and P2Y12 reaction units (PRU), as well as complication rates, angiographic and functional outcome were analyzed.

A total of 56 aneurysms (median size 5 mm, range 2.6-14.0 mm) in 54 patients (median age 58.5 years) were treated with stent-assisted coil embolization. Most aneurysms were located at the basilar tip (28.6%). Median pre-procedure ARU and PRU were 442.5 (range 363-594) and 123.5 (range 1-252), respectively. Approximately two-thirds of all procedures required at least one aspirin dose adjustment and 88.5% of procedures required at least one clopidogrel dose adjustment. There were two (3.6%) thromboembolic complications. One of the thromboembolic complications occurred in a patient where the pharmacy-mediated protocol was violated. There were no hemorrhagic complications. Last imaging follow-up demonstrated complete aneurysm occlusion in 83.9%.

In patients where the pharmacy-mediated antiplatelet protocol was followed, the thromboembolic complication rate was 1.8%. This complication rate compares favorably to those reported in large contemporary series. Nevertheless, the pharmacy-mediated protocol places a significant burden on both the patient and healthcare system.