Is the hypercoagulable state in atrial fibrillation mediated by vascular endothelial growth factor?

Background and Purpose-Tissue factor (TF an initiator of coagulation) and vascular endothelial growth factor (VEGF a marker of angiogenesis) are involved in the hypercoagulable state associated with malignancy We investigated their roles in chronic atrial fibrillation (AF) a condition also associated with increased risk of stroke and thromboembolism as well as a prothrombotic or hypercoagulable state Methods-We studied 25 patients with AF (20 men mean+/-SD age 62+/-13 years) who were compared with 2 control groups in sinus rhythm 30 healthy control subjects (17 men mean age 60+/-9 years) and 35 patient control subjects with coronary artery disease (CAD 27 men mean age 60+/-12 years) Plasma levels of TF VEGF and the VEGF receptor sFIt 1 were measured by enzyme linked immunosorbent assay Results-VEGF sFl 1 and TF were significantly different between the 3 groups with abnormal levels in AF and CAD patients compared with control subjects (P<0 001 P=0 022 and P=0 008 respectively) Among the AF patients TF levels were significantly correlated with VEGF (Spearman s r=0 65 P<0 001) and sFIt (r=0 54 P=0 006) levels Only TF and VEGF levels were significantly correlated in CAD patients (r=0 39 P=0 02) There were no significant correlations among the healthy control subjects Conclusions-Patients with chronic AF have high TF levels in keeping with the prothrombotic state associated with this arrhythmia The relationships between TF and VEGF and its receptor sFlt 1 in AF suggest a possible role for VEGF in the hypercoagulable state found in AF as seen in malignancy and atherosclerosis.