Aortic Stenosis and Acquired von Willebrand Disease: Lack of Association

Objectives: The association between aortic stenosis (AS) and acquired von Willebrand disease type 2A has been described. It may be present in up to 90% of patients with AS. Shear stress has been proposed as the underlying mechanism; however, the physiopathology of this condition is not completely understood. No specific treatment has been studied in this specific population besides aortic valve replacement (AVR). As a coadjuvant therapy, some cardiac surgery centers use desmopressin routinely. The authors report the first stage of an ongoing study designed to compare the effects of desmopressin versus placebo in patients with severe AS scheduled for AVR. Because of the different incidences of the acquired von Willebrand type 2A reported in the literature, the first stage was conducted to describe the incidence of this clinical association in the present population, allowing the sample size for the second stage of the study to be obtained. Design: A prospective cohort study. Setting: A single academic medical center. Participants: Thirteen patients with severe AS scheduled for AVR. Intervention: None. Measurements and Main Results: Patients with severe AS scheduled for AVR were studied preoperatively with a von Willebrand laboratory panel. Results were negative for acquired von Willebrand disease type 2A in all patients. The second stage of the trial was stopped. Conclusion: Contrary to previous reports, no correlation was found between AS and acquired von Willebrand disease type 2A. Further studies are needed to ascertain whether this lack of association is caused by a specific characteristic of the present population, the small sample size, or other factors. (C) 2011 Elsevier Inc. All rights reserved.