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Updated: Jun 5, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
Published on: August 14, 2017
No excess surgical blood loss in patients with acquired type 2A von Willebrand disease
Martin Majlund Mikkelsen1, Christian Fenger-Eriksen, Søren Paaske Johnsen
1Department of Cardiothoracic and Vascular Surgery & Institute of Clinical Medicine, Aarhus University Hospital, Skejby, Denmark. majlund@ki.au.dk
Objectives:
Acquired type 2A von Willebrand disease may develop as a consequence of aortic valve stenosis and is associated with varying degrees of bleeding tendency. It remains unknown, whether it portends excess blood loss during aortic valve replacement.
Design:
We consecutively enrolled 45 patients with severe aortic valve stenosis undergoing aortic valve replacement. Patients with acquired type 2A von Willebrand disease were identified measuring the von Willebrand factor high molecular weight multimer. Data on the intraoperative, early postoperative, and the total blood loss within 24 hours of surgery was obtained and compared between groups.
Results:
Acquired type 2A von Willebrand disease was found in 33% (n = 15/45) of the patients. Baseline characteristics were similar between groups. Patients with acquired type 2A von Willebrand disease neither had excess median intraoperative blood loss (375 ml (interquartile range 100-450 ml) vs. 350 ml (interquartile range 250-500 ml), p = 0.59) nor increased median total blood loss (695 ml (interquartile range 450-850 ml) vs. 752 ml (interquartile range 575-1035 ml), p = 0.41) as compared to patients without acquired type 2A von Willebrand disease.
Conclusion:
Acquired type 2A von Willebrand disease was not associated with increased blood loss during aortic valve replacement in patients with severe aortic valve stenosis.
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