International Journal of Cardiology

ISSN 2996-8215

International Journal of Cardiology | Vol. 2, No. 4, April 2011 | pp. 25–32

DOI: 10.46882/2011/IJC/000025

Original Research Article

Circulating Endothelial Progenitor Cells as a Predictor of Cardiovascular Events in Patients with Coronary Artery Disease

Hiroshi Yamamoto¹, Takashi Sato¹, Kenji Nakamura²

¹Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan

²Division of Cardiology, Tokyo Medical and Dental University, Tokyo, Japan

Abstract:
Endothelial dysfunction is a fundamental process driving the progression of atherosclerosis and plaque destabilization. Circulating endothelial progenitor cells (EPCs) derived from the bone marrow play a pivotal role in continuous vascular endothelial repair. This prospective study investigated the hypothesis that reduced levels of circulating EPCs predict long-term major adverse cardiovascular events (MACE) in patients with documented coronary artery disease (CAD). We quantified CD34+/KDR+ EPCs using flow cytometry in 210 patients with stable CAD undergoing diagnostic coronary angiography. Patients were followed for a median of 4.5 years for the occurrence of MACE, which included cardiovascular death, non-fatal myocardial infarction, and unstable angina requiring urgent revascularization. Patients were stratified into tertiles based on baseline EPC counts. MACE occurred in 48 patients (22.9%) during follow-up. The cumulative event-free survival rate was significantly lower in the lowest EPC tertile compared to the highest tertile (68.6% vs. 88.6%, log-rank p < 0.001). After adjusting for conventional cardiovascular risk factors, medications, and coronary disease severity via the SYNTAX score, a low circulating EPC count remained an independent predictor of future MACE (hazard ratio for lowest vs. highest tertile: 2.34, 95% CI: 1.41–3.88, p < 0.01). No significant correlations were observed between EPC levels and procedural access complications. Reduced levels of circulating endothelial progenitor cells independently predict long-term cardiovascular events in stable CAD patients, highlighting the clinical prognostic importance of endogenous vascular repair capacity.

Keywords: Endothelial progenitor cells, Coronary artery disease, Atherosclerosis, Endothelial function, Prognosis, Flow cytometry

Received: January 15, 2011; Revised: February 28, 2011; Accepted: March 15, 2011; Published: April 25, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 4, pp. 25–32, DOI: 10.46882/2011/IJC/000025