VWF and atrial fibrillation: For example, Lip et al. first showed that plasma vWF levels added to the CHADS2 and the Birmingham (precursor of CHA2DS2-VASc) schemes could help to refine risk stratification for vascular events (ischemic stroke, myocardial infarction or vascular death) in AF patients enrolled in the SPAF III trial17; however, they were not able to identify an independent association with the risk of stroke.