PB1356 - Intrinsic Platelet Dysfunction in Patients with Acute Intracerebral Hemorrhage

Background: One third of Intracranial hemorrhages (ICH) occur in patients taking antiplatelet medications; however, studies have shown that reduced platelet activity or dysfunction is associated with early ICH growth and worse functional outcomes. Platelets play an important role in clot stabilization and reduced platelet activity worsens ICH prognoses.

Aims: We hypothesize that ICH is due to inherent platelet dysfunction, and understanding it will be helpful to develop targeted interventions.

Methods: Thirty-eight patients with acute ICH were consented; however, not all had complete testing performed. Platelet function was determined by Thromboelastography (TEG) platelet mapping, platelet function analyzer (PFA-100®) and VerifyNow Aspirin and P2Y12 within 12 hours of symptom onset.

Results: Thirty-four patients had TEG platelet mapping performed while 36 patients had PFA and VerifyNow testing performed. The majority of patients 78.9% (n=30) in this cohort had a past medical history of hypertension. At presentation, 14 patients (36.8%) were on antiplatelet medication (8 reported NSAID use, 5 on clopidogrel and one reported taking both). TEG platelet mapping with ADP induced aggregation revealed platelet dysfunction in 61.7% (n=21/34), out of which 80.9% (n=17) were reported to not take antiplatelet medication, suggesting primary platelet dysfunction. Similarly, 66.7% (n=24/36) had abnormal PFA and VerifyNow results and 75% (n=18) reported no prior medication history. This data indicates reduced platelet activity without history of antiplatelet medication in the majority of patients presenting with ICH.

Conclusion(s): A substantial number of patients were found to have reduced platelet activity; however, the majority were not known to take antiplatelet medications. We hypothesize that intracerebral hemorrhage activates platelets resulting in circulating platelet dysfunction. Measures to correct platelet activity may be a feasible method to treat ICH and hematoma expansion. Future studies are designed identify potential targeted therapy to reduce hematoma expansion and improve outcomes.