Circulating biomarkers of angiogenesis as indicators of left ventricular systolic dysfunction amongst patients with coronary artery disease

Abstract

Patients with coronary artery disease (CAD) and left ventricular systolic dysfunction (LVSD) are often asymptomatic. Angiogenesis is implicated in the physiology of vascular repair and cardiac remodelling, and is one of many pathophysiological processes implicated in heart failure. We hypothesized that plasma indices associated with angiogenesis [angiogenin, vascular endothelial growth factor (VEGF), and angiopoietin (Ang)-1 and Ang-2] would be abnormal in CAD patients with LVSD, being correlated with EF and wall motion abnormalities (wall motion score) independently of underlying CAD (coronary atheroma score). We also evaluated the specificity of angiogenic 'biomarkers' in their detection of LVSD [ejection fraction (EF) <40%] amongst CAD patients. Using a cross sectional approach, we measured angiogenin, VEGF, Ang-1 and Ang-2 by ELISA in 194 CAD patients (aged 34-81 years) undergoing elective coronary angiography. Levels of angiogenin were inversely related with EF (r = -0.17, P = 0.02) and positively with coronary atheroma scores (r = 0.15, P = 0.04, but not independently of EF). Other angiogenic markers were unrelated to objective measures of LVSD but VEGF (P = 0.008) and Ang-2 (P = 0.015) were lower amongst those patients with heart failure. Angiogenin levels were related to wall motion scores (r = 0.16, P = 0.024). Heart failure has a modest impact on biomarkers of angiogenesis, in patients with CAD. Further research is warranted into the diagnostic and prognostic utility of biomarkers of angiogenesis, in this common cardiac condition.