Background: Left ventricular (LV) systolic function is a significant prognostic factor in patients after myocardial infarction (MI). Multiple angiogenic and inflammatory factors are involved in postinfarction LV remodelling process. In addition, CD34+progenitor cells mobilised from bone marrow and tissue niches participate in regeneration of the infarcted myocardium.

Aim: To examine relationships between LV ejection fraction (LVEF) and wall motion score index (WMSI) and the number ofCD34+ cells and plasma levels of vascular endothelial growth factor (VEGF), angiogenin and such inflammatory factors asinterleukin 6 (IL-6), interleukin 8 (IL-8), and high-sensitivity C-reactive protein (hsCRP) in patients with ST-elevation MI (STEMI).

Methods: The study group included 61 patients with STEMI treated with primary percutaneous coronary intervention (PCI)involving bare metal stent implantation. Plasma levels of the evaluated angiogenic and inflammatory factors were measured byflow cytometry at 4 time points (just before PCI, 24 h later, at hospital discharge, and 30 days after STEMI). LVEF and WMSIwere measured by echocardiography at hospital discharge, 1 month later, and 6 months later. We compared angiogenic andinflammatory factor levels in patients with no improvement of the LV systolic function during the follow-up (group 1, n = 22)vs. those with improved LV systolic function (group 2, n = 39).

Results: No differences in the levels of VEGF, angiogenin, IL-6, IL-8, and hsCRP, and the number of CD34+ cells wereobserved between the two groups. Despite this, we found significant negative correlations between hsCRP level and LVEF,and positive correlations between hsCRP level and WMSI in both patient groups, but these correlations were much strongerin group 1. We also found a significant negative correlation between WMSI at 6 months and the number of CD34+ cellsmeasured 24 h after PCI.

Conclusions: 1. Evaluation of plasma VEGF, angiogenin, IL-6, IL-8, and hsCRP levels and the number of CD34+ cells at differenttime points in patients with STEMI did not allow predicting the direction of changes in LVEF and WMSI. 2. Observedsignificant correlations between hsCRP level and LVEF and WMSI may suggest a harmful effect of inflammation on postinfarctionmyocardial remodelling. 3. A significant negative correlation between the number of CD34+ and WMSI suggests thatincreased mobilisation of these cells might have a beneficial effect on systolic function after MI.