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Updated: Oct 1, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
Published on: August 14, 2017
Relapse of thrombotic thrombocytopenic purpura associated with decreased VWF cleaving activity
Mark P Anstadt1, John M Carwile, Carrie K Guill
1manstadt@mail.mcg.edu
Abstract:
Thrombotic thrombocytopenic purpura (TTP) is an uncommon syndrome characterized by reversible, systemic aggregation of platelets in the microcirculation and disseminated microvascular thrombosis. Surgery may precipitate TTP and has been associated with relapse in some patients. However, relapse of this life-threatening disorder is unpredictable. We report a patient with an antecedent history of TTP who experienced a relapse after elective cardiac surgery. In this case, decreased von Willebrand factor (vWF)-cleaving metalloproteinase activity and an inhibitor of this endogenous enzyme were demonstrated preoperatively. These findings suggest that decreased vWF-cleaving metalloproteinase activity and/or the presence of its inhibitor may predict an increased risk for surgical-associated relapse of TTP.
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