Abstract 16879: The Release of Mir-29b into the Coronary Circulation Correlates With Thin-cap-fibroatheroma, Positive Coronary Remodeling and Decreased Plaque Fibrosis in Patients With Stable Cad
Introduction: Circulating microRNAs (miRs) can be measured in the blood and may reflect pathophysiologically relevant processes. MiR29b plays a crucial role in matrix degradation and tissue fibrosis. We hypothesized that circulating levels of miR29b may be associated with coronary atherosclerotic plaque morphology and arterial remodeling in patients with CAD.
Methods: Coronary atherosclerotic plaque phenotype and extent of remodeling were assessed by optical coherence tomography (OCT) in 47 patients with stable CAD undergoing coronary angiography. Circulating miR29b levels were measured in blood samples simultaneously obtained from the aortic bulb (Ao) and coronary venous sinus (CVS), and the transcoronary concentration gradients were calculated in order to ensure the coronary release of miR29b.
Results: CVS levels of miR29b were significantly and inversely correlated with the extent of plaque fibrosis (r=-0.38, p=0.008), but not with other phenotypic features of coronary plaques. Likewise, miR29b levels in the CVS directly correlated with the extent of outward remodeling of coronary atherosclerotic plaques (r=0.373, p=0.010). Most importantly, transcoronary concentration gradients of miR29b were significantly related to the presence of thin-cap-fibroatheroma (TCFA, r=0.364, p=0.008) and to the extent of positive remodelling of coronary plaques (r= 0.308, p=0.035). In order to establish whether circulating miR29b levels reflect pathophysiological mechanisms within the coronary arterial wall, we measured circulating levels of ADAMTS7, a secreted disintegrin and metalloproteinase involved in arterial remodeling and an experimentally well-established target of miR29b. Indeed, CVS concentrations of miR29b were closely and inversely correlated with ADAMTS7 levels (r=-0.64, p<0.001, N=103).
Conclusions: The release of miR29b into the coronary circulation is associated with decreased plaque fibrosis, increased extent of TCFA and arterial remodeling of coronary atherosclerotic plaques. The close inverse correlation with its target, ADAMTS7, indicates that circulating levels of miR29b reflect pathophysiologically processes in the atherosclerotic wall and may be useful as prognostic biomarkers in patients with CAD.
Author Disclosures: R. De Rosa: None. N. Boeckel: None. D. Leistner: None. S. Reis: None. C. Thome: None. T. Roexe: None. S. Fichtlscherer: None. S. Dimmeler: None. A.M. Zeiher: None.
- © 2016 by American Heart Association, Inc.