0295: Increased intracardiac VEGF and VWF levels revealed low grade inflammatory process and progressive endothelial damage in patients with atrial fibrillation

Abstract

Endothelial dysfunction seems to play a pivotal role in atrial fibrillation (AF). The purpose of this study was to investigate the relationship between AF and vascular endothelial growth factor (VEGF) and to investigate the effect of different clinical forms of AF on plasma concentration of Von Willebrand Factor (vWF) at different levels of circulatory tree, both intracardiac and extracardiac. Peripheral (Pf), left atrial (LA), and coronary sinus (CS) blood samples were obtained during cardiac catheterization from 52 patients with paroxysmal AF (PAF), 36 with persistent AF (PsAF), and 17 control subjects (Ct) with Wolff-Parkinson-White syndrome. Plasma levels of VEGF and vWF were measured at the three sampled sites. Peripheral VEGF levels were higher in both PAF and PsAF patients than in controls (P≤0.03). Left atrial VEGF levels were higher in paroxysmal AF (P = 0.05), but not in persistent AF (P = 0.32), compared with controls. Coronary sinus and pulmonary vein VEGF levels did not differ significantly among groups. (Fig 1). Compared with Ct, patients with PAF had higher LA plasma levels of vWF (P=0.004), but similar Pf and CS levels (both P>0.30). In contrast, patients with PsAF had higher plasma concentrations of vWF in Pf (P=0.04), LA (P<0.001), and CS (P=0.04) samples compared with Ct. Left atrial plasma concentrations of vWF in patients with PsAF were also higher than in the PAF group (P=0.04). (Fig 1, next page). This study suggests that inflammatory process in AF is of low grade. The heart itself is the most likely source of high left atrial VEGF; however, this disorder appears to be a transient event in AF history. AF patients presented significantly higher plasma concentrations of vWF. This study suggests an association between the clinical evolution of AF and the progression of endothelial dysfunction. Further studies will have to establish the exact mechanisms that link endothelial dysfunction and stroke in the context of AF. Abstract 0295 – Figure: VEGF and Vwf plasma levels in the 3 study groups