Introduction: Prospective, randomized control trials in the cardiac literature have shown that periprocedural platelet reactivity value (PRU) < 208 is associated with lower rate of adverse cardiac events. This study is aimed to investigate whether the established optimal PRU value for cardiac procedure has similar effect on neurovascular outcome in patients undergoing Pipeline Embolization Device (PED) placement.

Methods: Medical records of patients underwent PED placement from April 2011 to August 2013 were reviewed. Variables including age, gender, smoking status, aneurysm characteristics, pre-procedure antiplatelet regiment, pre-procedure PRU, pre-procedure aspirin reaction unit (ARU), procedure time, number of PEDs deployed, and perioperative neurovascular complications up to 4 weeks after PED placement were recorded. Fisher’s exact test and multivariate regression analysis was performed to identify independent predictors of perioperative complications in these patients.

Results: Seventy-four patients underwent PED placement during the study period. Seven patients (8.97%) had symptomatic thromboembolic complications after procedure, while 50.9% patients had DWI changes on MRI. Length of the procedure > 116 min was the greatest risk factor for symptomatic thromboembolic event (p <0.001). PRU > 208 did not reach statistical significance as a predictive risk factor in our cohort (p=0.111). None of the other identified variables conferred higher risk for either symptomatic thromboembolic events /DWI changes with statistical significance.

Conclusions: In our cohort, length of the procedure > 116 min was the greatest risk factor for symptomatic thromboembolic event (p <0.001). Although there was a trend, pre-procedural PRU >208 was not a statistically significant risk factor for symptomatic thromboembolic events. Our practice of re-loading patients who had high pre-procedure PRU value with 6oomg clopidogrel immediately after procedure may have reduce the incidence of symptomatic stroke in clopidogrel hypo-responders. Larger, prospective studies are needed to further validate the correlation between pre-procedure PRU value and thromboembolic complications.

Patient Care: Our study brings attention to the importance of procedure time and pre-procedure PRU value and their potential impact on thromboembolic complications. By identifying these potential risk factors, the safety profile of PED placement can be improved and potential neurovascular complications can be reduced or avoided.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the impact of pre-procedure PRU value and procedure time on incidence of thromboembolic events in patients undergoing Pipeline Embolization Device placement 2) Discuss, in small groups, the steps that could be taken to reduce thromboembolic complication in patients undergoing Pipeline stent placement 3) Identify an effective treatment strategy for dealing with patients who are hypo-responders to clopidogrel to minimize thromboembolic complications in this group of patients.

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