OC 27.3 - Whole-blood rotational thromboelastometry in patients with bleeding disorder of unknown cause

Sunday, June 23, 2024

15:15 – 15:30 ICT

Room: 210 A-D

Presenting Author(s)

Dino Mehic

PhD Student/MD
Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna
Vienna, Wien, Austria

Co-Author(s)

Tim Dreier, MD

PhD-Student
Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna
Vienna, Wien, Austria
Jasmin Rast

PhD Student/MD
Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna
Vienna, Wien, Austria
CD

Christa Drucker

Technician - Lab manager
Department of Clinical Pharmacology
Vienna, Wien, Austria
Bernd Jilma, MD

Professor
Department of Clinical Pharmacology, Medical University Vienna
Vienna, Wien, Austria
Cihan Ay, MD

Professor
Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna
Vienna, Wien, Austria
Ingrid Pabinger

Professor
Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna
Vienna, Wien, Austria
Johanna Gebhart

Assoc. Professor
Department of Internal Medicine I, Clinical Division of Hematology and Haemostaseology, Medical University of Vienna
Vienna, Wien, Austria

Background: Bleeding disorder of unknown cause (BDUC) is diagnosed in patients with a bleeding tendency when hemostatic tests reveal no underlying pathology. Rotational thromboelastometry (ROTEM), a whole-blood viscoelastic global assay, assesses various aspects of coagulation, including fibrinolysis, and captures the impact of erythrocytes and platelets on hemostasis.

Aims: To analyze ROTEM parameters in BDUC patients and its association with clinical parameters.

Methods: Patients with BDUC (n=436) from the Vienna bleeding biobank (VIBB, EC no. 603/2009) were compared to 100 age-matched healthy controls (HC). Viscoelastic clot parameters were assessed with non-activated ROTEM® (EM International, Munich, Germany): clotting time (CT, s), clot formation time (CFT, s), maximum clot firmness (MCF, mm) and maximal lysis (ML, %).

Results: Patient characteristics are shown in Table 1. BDUC patients had longer CT, lower CFT, and reduced ML than HC. After adjusting for potential confounders, the mean differences in ROTEM parameters were even higher for prolonged CT and impaired ML, MCF was even higher in BDUC (Table 1).
In multivariable regression, sex was negatively associated with CT (β=-44.1, p=0.015), factor VIII with CT and MCF (β =-0.6, p=0.006; β =0.02, p=0.02), hemoglobin with CT (β =26.1, p< 0.001), CFT (β =20.9, p< 0.001), and ML (β =-0.4, p=0.044), fibrinogen with MCF(β=0.03, p< 0.001), and age with ML (β =-6.9, p< 0.001).
ROTEM parameters did not show a significant correlation with the ISTH-BAT (CT: r=0.01, CFT: r=0.03, MCF: r=.0.05, ML: r=-0.14) or Vicenza (CT: r=0.03, CFT: r=0.03, MCF: r=0.02, ML:-0.12) bleeding severity scores.
A model differentiating BDUC patients from HC using a multivariable logistic regression model combining all four ROTEM parameters yielded an acceptable AUC-value of 0.733 (Figure 1).

Conclusion(s): Whole-blood thromboelastometry revealed impaired hemostatic capacity in BDUC; however, our partly inconclusive data do not currently fully support ROTEM as a screening assay in BDUC.