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Von Willebrand Factor Ristocetin Co-factor Activity to Von Willebrand Factor Antigen Level Ratio for Diagnosis of Acquired Von Willebrand Syndrome Caused by Aortic Stenosis

Abstract

Background: Severe aortic stenosis (AS) causes acquired von Willebrand syndrome by the excessive shear stress-dependent cleavage of high molecular weight multimers of von Willebrand factor (VWF). While the current standard diagnostic method is so-called VWF multimer analysis that is western blotting under nonreducing conditions, it remains unclear whether a ratio of VWF Ristocetin co-factor activity (VWF:RCo) to VWF antigen levels (VWF:Ag) of <0.7, which can be measured with an automated coagulation analyzer in clinical laboratories and is used for the diagnosis of hereditary von Willebrand disease.

Objectives: To evaluated whether the VWF:RCo/VWF:Ag is useful for the diagnosis of AS-induced acquired von Willebrand syndrome.

Methods: VWF:RCo and VWF:Ag were evaluated with the VWF large multimer index as a reference, which represents the percentage of a patient's VWF high molecular weight multimer ratio to that of standard plasma in the VWF multimer analysis.

Results: We analyzed 382 patients with AS having transaortic valve maximal pressure gradients of >30 mmHg, 27 patients with peripheral artery disease, and 46 control patients free of cardiovascular disease with osteoarthritis, diabetes, and so on. We assumed a large multimer index of <80% as loss of VWF large multimers since 59.0% of patients with severe AS had the indices of <80%, while no control patients or patients with peripheral artery disease, except for 2 patients, exhibited the indices of <80%. The VWF:RCo/VWF:Ag ratios, measured using an automated blood coagulation analyzer, were correlated with the indices (r = 0.470,  < .001). When the ratio of <0.7 was used as a cut-off point, the sensitivity and specificity to VWF large multimer indices of <80% were 0.437 and 0.826, respectively.

Conclusion: VWF:RCo/VWF:Ag ratios of <0.7 may indicate loss of VWF large multimers with high specificity, but low sensitivity. VWF:RCo/VWF:Ag ratios in patients with AS having a ratio of <0.7 may be useful for monitoring the loss of VWF large multimers during their clinical courses.

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References
1.
Pipe S, Montgomery R, Pratt K, Lenting P, Lillicrap D . Life in the shadow of a dominant partner: the FVIII-VWF association and its clinical implications for hemophilia A. Blood. 2016; 128(16):2007-2016. PMC: 5073181. DOI: 10.1182/blood-2016-04-713289. View

2.
Sadler J . Biochemistry and genetics of von Willebrand factor. Annu Rev Biochem. 1998; 67:395-424. DOI: 10.1146/annurev.biochem.67.1.395. View

3.
Franchini M . Hemostasis and aging. Crit Rev Oncol Hematol. 2006; 60(2):144-51. DOI: 10.1016/j.critrevonc.2006.06.004. View

4.
Wise R, Dorner A, Krane M, Pittman D, Kaufman R . The role of von Willebrand factor multimers and propeptide cleavage in binding and stabilization of factor VIII. J Biol Chem. 1991; 266(32):21948-55. View

5.
Vlot A, Koppelman S, van den Berg M, Bouma B, Sixma J . The affinity and stoichiometry of binding of human factor VIII to von Willebrand factor. Blood. 1995; 85(11):3150-7. View