Modulating factors of progenitor stem cell kinetics in STEMI patients undergoing primary angioplasty - a pilot study.

AIMS To investigate the circulating progenitor stem cells (cPCs) count evolution during seven days hospitalization period in ST segment elevation myocardial infarction (STEMI) patients, and to correlate their evolution with some clinical and angiographic parameters. MATERIALS AND METHODS Twelve Caucasian patients with STEMI undergoing primary percutaneous coronary intervention (PCI) were enrolled. Blood samples were obtained in the emergency room and then daily, for seven days, we evaluated the number of cPCs (CD34+CD45+, CD133+CD34+CD45+, KDR+CD34+CD45+ and KDR+CD133+CD34+CD45+) by flow cytometry using fluorochrome-marked specific monoclonal antibodies. RESULTS There is a statistically significant increase in cPCs counts in the following days after STEMI, with a different behavior depending on their phenotype. Mature cPCs (CD34+CD45dim, KDR+CD34+CD45dim) have two fairly similar peaks, first around the third day of evolution followed by a short decrease and a new raise in the seventh day, the more immature cPCs (CD133+CD34+CD45dim, KDR+CD133+CD34+CD45dim) have just one spike on the third day, and then almost disappear from the peripheral circulation. In a multivariate regression analysis, preprocedural TIMI (Thrombolysis In Myocardial Infarction) flow, postprocedural myocardial blush and LVEF (Left Ventricular Ejection Fraction) proved to be independent predictors for cPCs variation in the first week after STEMI. CONCLUSIONS In our study, we demonstrated that all four main phenotypes of circulating progenitor stem cells boosted up in the next days after STEMI, with different patterns depending on cell type; preprocedural TIMI flow, postprocedural myocardial blush and LVEF proved to be independent predictors for cPCs mobilization in the first days after STEMI.