PB1241 - Rotational thromboelastometry (ROTEM) in patients with bleeding of unknown cause: evidence for hemostatic imbalance

Tuesday, July 12, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

DM

Dino Mehic, MD

Resident physician
Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
Vienna, Wien, Austria

Co-Author(s)

BJ

Bernd Jilma

Specialist for Internal Medicine
department of Clinical Pharmacology
Vienna, Wien, Austria
CS

Christian Schörgenhofer

Research associate
Department of Clinical Pharmacology, Medical University of Vienna
Vienna, Wien, Austria
MC

Meaghan Colling, MD

Clinical Research Fellow
Medical University of Vienna
Vienna, Wien, Austria
Cihan Ay, MD

Professor, Head of the Thrombosis and Haemostasis Research Group
Clinical Division of Haematology and Haemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
Vienna, Wien, Austria
Ingrid Pabinger, MD

Co-Head of the Thrombosis and Haemostasis Research Group
Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
Vienna, Wien, Austria
Johanna Gebhart, MD, PhD

Ap. Prof. Dr. PhD
Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
Vienna, Wien, Austria

Background: In up to 75% of patients with a mild to moderate bleeding disorder (MBD) an underlying cause cannot be found despite extensive laboratory investigations (bleeding of unknown cause, BUC). Patients with BUC do not differ in their bleeding phenotype from patients with an established MBD. Whole-blood thromboelastometry (ROTEM) measures diverse aspects of coagulation including fibrinolysis and captures the influence of erythrocytes, leucocytes and platelets on hemostasis.

Aims: To analyze clinical factors influencing ROTEM measurements in BUC patients and to compare the hemostatic state assessed by ROTEM between patients with BUC and an established MBD.

Methods: Patients from the Vienna bleeding biobank (VIBB, EC no. 603/2009) were analyzed (Gebhart et al, Haemophilia, 2018). Viscoelastic clot measurement was performed with non-activated ROTEM® (EM International, Munich, Germany) and the following parameters were analyzed: clotting time (CT, sec, time from analysis start until start of clot formation), clot formation time (CFT, sec, time needed to form a clot), maximum clot firmness (MCF, mm, peak amplitude of the clot) and maximal lysis (ML, %, expression of clot lysis in % of MCF).

Results: ROTEM data were available of 513/714 (71.8%) patients included in VIBB. The mean (SD) age was 41.4 (15.0) years, 425 (80.3%) were women and 252 (47.6%) patients had blood group O.
In BUC patients ROTEM measurements were significantly associated with age, sex, blood group O (vs. non-O) and the bleeding score in multivariable linear regression (Table 1).
BUC patients had similar ROTEM measurements than patients with platelet function defects or von Willebrand disease, whereas patients with clotting factor deficiency had longer CT and CFT, a lower MCF and higher ML (Table 2).

Conclusion(s): Hemostatic capacity measured by ROTEM is similar in patients with BUC and those with mild primary hemostatic bleeding disorders. Our data support the hemostatic imbalance in patients with BUC.