“…9 -11 However, this study is the first to demonstrate that raised levels of one such marker (vWf) can predict clinical outcome (including stroke) in AF, although uncertainty remains as to whether it is AF itself or simply the presence of additional underlying cardiovascular conditions that determines elevation of these markers in AF. 13,22,23 Because of the exclusion of patients assigned adjusteddose warfarin, our cohort featured predominantly low-to moderate-risk patients (thus, the number of incident strokes were relatively few), and all were treated with aspirin, factors that must be considered before applying our study findings to all populations with AF. Nonetheless, it is notable that although plasma levels of vWf (an index of endothelial damage/dysfunction) predicted stroke and the composite end point of stroke, MI, or vascular death among our whole cohort of 994 AF patients, plasma levels of sP-sel (an index of platelet activation) did not, and in a previous substudy from the SPAF III trial, 4 other prothrombotic markers (fibrinogen, -thromboglobulin, prothrombin fragment F1.2, and factor V Leiden) also failed to predict outcome.…”