Characteristics of blood tests in patients with acute cerebral infarction who developed symptomatic intracranial hemorrhage after intravenous administration of recombinant tissue plasminogen activator

OBJECTIVE: Patients suspected as having acute ischemic stroke usually undergo blood tests, including coagulation-related indexes, because thrombocytopenia and coagulopathy are contraindications for recombinant tissue plasminogen activator (rtPA) administration. We aimed to identify blood test indexes associated with symptomatic intracranial hemorrhage (sICH) in patients with acute ischemic stroke who received intravenous rtPA. METHODS: This retrospective observational study included patients diagnosed with acute ischemic stroke who were treated with intravenous rtPA at the emergency department of a tertiary hospital in Seoul between February 2008 and January 2018. Blood test indexes were compared between the sICH and non-sICH groups. Logistic regression and receiver-operating characteristic curve analyses were performed. RESULTS: In this study, 375 patients were finally included. Of 375 patients, 42 (11.2%) showed new intracranial hemorrhage on follow-up brain computed tomography, of whom 14 (3.73%) had sICH. Platelet count, aspartate aminotransferase and lactate dehydrogenase levels were significantly different between the sICH and non-sICH groups, and platelet count showed statistical significance in the regression analysis. Significantly lower platelet counts were observed in the sICH group than in the non-sICH group (174,500 vs. 228,000/mm(3), P=0.020). The best cutoff platelet count was 195,000/mm(3), and patients with platelet counts of <195,000/mm(3) had a 5.4- times higher risk of developing sICH than those with platelet counts of ≥195,000/mm(3). CONCLUSION: Platelet count was the only independent parameter associated with sICH among the blood test indexes. Mild thrombocytopenia may increase the risk of sICH after intravenous administration of rtPA.