Introduction/purpose There are conflicting reports regarding the utility of platelet function tests in patients undergoing treatment with Pipeline Embolization Device (PED) for intracranial aneurysms. Herein, we report the correlation between platelet function testing and the incidence of complications in a series of patients who underwent PED placement. Unlike prior reports, patient procedures at our institutions were not canceled or postponed based on platelet function tests.

Materials and methods A retrospective analysis of the patients with unruptured, intracranial aneurysms treated with PED device (s) at two academic hospitals was performed between June 2012 and March 2015. Patient demographics, location of intracranial aneurysm, size and number of PEDs deployed were documented for each patient. The dual antiplatelet regimen prior to and following PED deployment was documented. All patients received Aspirin 325 mg and Plavix 75 mg daily, 5 days prior to the procedure, and continued the treatment for six months. Platelet function testing was performed on the day of or the day after PED deployment using the VerifyNow (Accumetrics) system for Aspirin (ARU) and P2Y12 Reaction Units (PRU) (Plavix). Therapeutic platelet function testing for Aspirin was defined as an ARU less than 550. PRUs > 70 or < 208 were taken to be in the therapeutic range for Plavix. Where possible, the dual anti-platelet regiment was modified prior to or after the procedure if the ARU/PRU values were abnormally high or low; but this was not possible with every patient and in some patients the regimen was not altered. Any immediate and post-procedure thrombotic and hemorrhagic complications were documented.

Results A total of 39 PEDs were deployed in 32 procedures performed on a total of 27 patients with unruptured, intracranial aneurysms (average age, 55 ± 14 years; 4 (15%) male). There were 3 (9%) procedures in which neither platelet function test was obtained. No procedure was delayed or canceled based on the results of platelet function testing. There were no immediate or delayed thrombotic or hemorrhagic complications. Clinical follow up ranged from 18 days to 2 years post procedure.

Conclusion In our experience, the wide range of ARU and PRU values did not have any impact on the incidence of thromboembolic or hemorrhagic complications in the peri-operative or immediate post- operative period. It may be unwise to cancel or postpone PED procedures based on single PRU value measurements, since this can lead to unnecessary cost escalations for the patient and the facility. A well designed randomized control trial may offer the best answer regarding the utility of platelet function testing in the treatment of patients with intra-cranial aneurysms using flow diverters.

Disclosures H. Zacharatos: None. D. Sandhu: None. R. Tummala: None. A. Grande: None. B. Jagadeesan: None.