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Updated: Mar 19, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
Published on: August 14, 2017
Relationship between spontaneous echo contrast in the thoracic aorta and plasma von Willebrand factor
Takuya Inoue1, Makoto Suzuki2, Atsushi Namiki3
1Department of Cardiovascular Medicine, Toho University Ohashi Medical Center, 2-17-6 Ohashi, Meguro, Tokyo, 153-8515, Japan. tinoue@oha.toho-u.ac.jp.
Purpose:
To clarify the relationships between spontaneous echo contrast (SEC) detected by transesophageal echocardiography (TEE) and coagulopathy, ultrasonographic findings that may correlate to biochemical coagulation markers were examined.
Methods:
TEE was performed on 49 consecutive patients (mean age 64 ± 14 years; 28 men, 21 women). Blood samples were taken at the same time as TEE was carried out. Aortic SEC (Ao-SEC) and left atrial SEC (LA-SEC) were classified into three grades: absent, mild and marked. Levels of von Willebrand factor (vWF), thrombin antithrombin III complex (TAT), prothrombin fragments 1+2 (F1+2) and fibrinopeptide A (FPA) were measured.
Results:
Mean plasma vWF levels by Ao-SEC grade were 144 ± 39% for absent, 177 ± 55% for mild and 210 ± 73% for marked, with significantly higher levels in the Ao-SEC marked group than in the Ao-SEC absent group (P < 0.05). Mean plasma vWF levels by LA-SEC were 185 ± 73% for absent, 180 ± 49% for mild and 201 ± 62% for marked, with no significant differences apparent between groups. Moreover, no relationships were identified between Ao-SEC grade and plasma levels of coagulation indicators TAT, F1+2 and FPA.
Conclusion:
Plasma vWF levels correlated to grade of aortic SEC. Characteristics of the coagulation system differ between Ao-SEC and LA-SEC. Ao-SEC offers a clinical indicator of platelet thrombus formation.
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