Abstract 19204: Transcoronary Gradients of Soluble Fms-Like Tyrosine Kinase 1 Very Early After ST-Elevation Myocardial Infarction
The soluble Fms-like Tyrosine Kinase 1 (sFLT-1) is known to be elevated in serum of patients with acute coronary syndromes (ACS). Recent experimental studies suggested that hypoxia rapidly induces sFLT-1 in endothelial cells, thereby counteracting vessel permeability and improving oxygen supply in tumors. In order to establish a role of sFLT-1 in myocardial hypoxia, we investigated whether a gradient across the coronary circulation could be identified for sFLT-1 in patients with ACS. Blood samples were simultaneously obtained from the aortic bulb (Ao) and the coronary venous sinus (CVS) of 32 patients undergoing coronary angiography for stable coronary artery disease (CAD, n=15), unstable angina/NSTEMI (UA/NSTEMI, n=8) or STEMI (n=9) and sFLT-1 levels were measured by ELISA (pg/ml). Transcoronary gradients were expressed as delta of concentration ([CVS]-[Ao]). Consistent with results of previous studies, systemic levels of sFLT-1 in the aorta were significantly increased (4-fold; p<0.003) in patients with STEMI, as compared to CAD or UA/NSTEMI. Importantly, in patients with thrombotic occlusion of the infarct-related artery (IRA) presenting within 3 hours from the beginning of chest pain a significant transcoronary gradient (CVS>Ao) was observed for sFLT-1 (p=0.001), due to a profound increase of sFLT-1 levels in the CVS. In contrast, no relevant transcoronary gradients were observed in patients without occlusion of IRA at coronary angiography or reaching the cardiac catheterization laboratory later than 3 hours after the beginning of chest pain. The presence of a CVS-Ao gradient in patients presenting within 3 hours from the beginning of chest pain suggests an early release of sFLT-1 into the coronary circulation during myocardial hypoxia due to thrombotic occlusion of the IRA. These findings support the concept that sFLT-1 represents an early marker of myocardial hypoxia. Larger studies are needed to confirm the prognostic significance of sFLT-1 in patients with ACS.
- © 2010 by American Heart Association, Inc.