A prospective diagnostic accuracy study evaluating rotational thromboelastometry and thromboelastography in 100 patients with von Willebrand disease

Introduction Rotational thromboelastometry (ROTEM®) and thromboelastography (TEG®) are increasingly used in the perioperative and emergency assessment of bleeding tendencies. The diagnostic value of ROTEM and TEG for von Willebrand disease (VWD) remains to be established. Aim To investigate whether ROTEM and TEG can discriminate patients with VWD from healthy controls. Methods Rotational thromboelastometry and TEG whole blood coagulation profiles were compared between VWD patients (n = 100) and healthy controls (n = 89). Measures of diagnostic accuracy were calculated, including sensitivity, specificity and receiver operating characteristic (ROC) curve. Results Prolonged TEG R‐time had a positive and negative predictive value (PPV, NPV) of 0.84 and 0.68 respectively. TEG clotting index (CI) had a PPV of 1.00 and an NPV of 0.60. Both R‐time and CI had a high specificity and accurately discriminated VWD patients from healthy controls, with an ROC area under the curve of 0.85 and 0.99 respectively. In multivariate analysis, low FVIII levels, but not von Willebrand factor (VWF) antigen or activity, determined hypocoagulable TEG R (R2 = 0.35) and CI levels (R2 = 0.51). The ROTEM coagulation profiles of VWD patients did not differ from healthy controls. Conclusions Thromboelastography R and CI accurately discriminated VWD patients from healthy controls, partly through the detection of low FVIII levels. The test's performance may be improved through adjustment of the test thresholds to a local reference population. Both intrinsic pathway‐activated (INTEM) and tissue factor pathway‐activated (EXTEM) ROTEM were of limited diagnostic value in VWD.