F7 and atrial fibrillation: In addition, morbid obesity is predisposed to increased levels of the von Willebrand factor, prothrombin, factor VII, factor VIII, and fibrinogen, resulting in an increased incidence of thromboembolic events [16]. Moreover, Vyas and Lambiase suggested that the hemodynamic changes associated with high BMI may alter cardiac structure and physiology, increasing susceptibility to the development of AF [17].