OBJECTIVETo investigate the changes in plasma levels of vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1 (SDF-1) and in peripheral CD34(+) cells in patients with acute myocardial infarction (AMI), and explore their role in AMI.

METHODSEnzyme-linked immunoassay (ELISA) was employed for measuring the levels of VEGF and SDF-1 in AMI patients on days 1, 3, 7, 10, and 14 of onset and in normal control subjects. The absolute counts of CD34(+) in the peripheral blood were measured on days 1, 7, and 14 by flow cytometry in AMI patients, with their myocardial enzyme and troponin I detected and electrocardiography (ECG) and echocardiography (UCG) recorded.

RESULTSPeripheral CD34(+) cells obviously increased on day 7 after AMI onset (2.35-/+0.72/microl vs 1.48-/+0.49/micro, P<0.05). VEGF levels were significantly higher in AMI patients than in the control subjects, reaching the peak level and on day 14 (197.56-/+39.87 vs 53.79-/+18.12 pg/ml, P<0.01). SDF-1 level obviously decreased on day 1 after AMI onset (1683.12-/+224.79 vs 2178.67-/+265.34 pg/ml, P<0.01), followed by gradually increased to the control level. Obvious correlation was noted between the level of VEGF on day 7 and the peak level of peripheral CD34(+) cells, and the peak plasma VEGF level was obviously associated with the peak serum CK-MB and troponin I levels.

CONCLUSIONThe stem cells are mobilized into the peripheral blood in the event of AMI. Obviously increased VEGF level following AMI may persist for at least 2 weeks, whereas SDF-1 level undergoes temporary decrement after AMI. The dynamic changes of VEGF and SDF-1 can be related to the mobilization and homing of the stem cells to the injured myocardium.