Endothelial Progenitor Cell Function in Patients With Coronary Chronic Total Occlusion and its Relationship With Collateral Circulation

Aim. To evaluate the relationship between endothelial progenitor cell (EPC) count and function and collateral circulation in coronary chronic total occlusions (CTOs). Methods. A total of 20 consecutive patients with successfully treated CTO lesions were included during a period of 12 months. EPC count and function were evaluated by flow cytometry and colony-forming unit (CFU) analysis at baseline (before percutaneous coronary intervention) and at 1-year follow-up. Patients were classified, according to Rentrop classification at the baseline angiography, as group 1 (Rentrop 3; n = 7) and group 2 (Rentrop