Impact of thrombocytopenia on hemorrhagic complications after endovascular therapy for acute large vessel occlusion: Sub-analysis of RESCUE-Japan registry 2

Background: Endovascular treatment (EVT) for patients with large vessel occlusion (LVO) and concurrent thrombocytopenia raises concerns about hemorrhagic complications. We examined the association between thrombocytopenia and clinical outcomes after EVT.Methods: This is a sub-analysis of the RESCUE-Japan Registry 2, a nationwide registry that enrolled 2420 consecutive acute LVO patients. We evaluated the clinical outcomes in patients who underwent EVT according to their platelet count on admission (Moderate/Severe, < 100 x 10(9) /L; Mild, 100 to =150 x 10(9)/L; Normal, =; 150 x 109/L). The outcomes included any and symptomatic intracranial hemorrhage (ICH) after EVT, and modified Rankin Scale (mRS) at 90 days.Results: Of 1268 patients who underwent EVT, the Moderate/Severe and Mild groups consisted of 41 (3.2%), and 193 (15.2%) patients. Any ICH occurred in 37%, 35%, and 24% of Moderate/Severe, Mild, and Normal group patients, respectively, and the adjusted ORs (95% CIs) were 1.50 (0.71-3.18) for Moderate/Severe and 1.87 (1.28-2.73) for Mild, compared to the Normal group (p for trend = 0.004). Symptomatic ICH increased with the severity of thrombocytopenia (9.8% vs 3.6% vs 2.1%), and adjusted ORs were 4.43 (1.16-17.0) in Moderate/ Severe and 1.85 (0.71-4.86) in Mild (p for trend = 0.10). Mortality was significantly associated with the severity of thrombocytopenia (p for trend = 0.005), and adjusted ORs were 3.26 (1.29-8.26) in the Moderate/Severe and 2.76 (1.58-4.84) in the Mild groups.Conclusions: Thrombocytopenia in LVO patients was not rare and associated with the incidence and manifestation of ICH after EVT.