Sonorheometry parameters during dabigatran reversal with idarucizumab for major bleeding.

Bleeding during oral anticoagulant therapy is currently codified by expert guidelines. Monitoring coagulation during bleeding events remains challenging. This study aimed to assess viscoelastic hemostatic assays (VHAs) using the Quantra analyzer (HemoSonics) in dabigatran-treated patients with International Society on Thrombosis and Haemostasis major bleeding. We conducted a prospective, multicenter study at 2 university hospitals from January 2021 to December 2023. VHA were evaluated using whole blood sample collected upon emergency admission and 30 minutes after reversal therapy. Six dabigatran-treated patients with major bleeding were included in this study and received idarucizumab: 4 patients with an intracranial bleeding and 2 with gastrointestinal major bleeding. Prior to reversal therapy, clot time (CT) and clot time with heparinase coagulation time (CTH) were prolonged beyond normal range for all patients but clot stiffness (CS) was notably low, indicating a hypocoagulable state. After idarucizumab administration, both CT (median [interquartile range], 179.5 s [169.3-238.5 s] vs 126 s [96-135.5 s]; P = .002) and CTH (181.5 s [166.3-224.3 s] vs 118.5 s [99.5-121.3 s], P = .002) significantly decreased, whereas CS increased significantly (median [interquartile range], 18 hPa [12.3-24.3 hPa] vs 26.6 hPa [25.5-33.8 hPa]; P = .03), all values falling within the normal range. Median anti-IIa activity at emergency arrivals decreased under 30 ng/mL 30 minutes, 6 hours, and 24 hours after idarucizumab administration (P = .0008). No complications were reported during follow-up. After idarucizumab administration, VHA demonstrated significant reductions in CT and CTH, with a corresponding increase in CS within normal ranges. These findings suggest that VHA using the Quantra analyzer may be a valuable tool in assessing the presence of dabigatran and the efficacy of idarucizumab reversal in patients with major bleeding. SIGNIFICANCE STATEMENT: This study highlights viscoelastic hemostatic assays using the Quantra analyzer to monitor reversal therapy in dabigatran-treated patients with major bleeding. It demonstrates the efficacy of idarucizumab in restoring coagulation parameters, offering insights into clinical management.