Association of platelet-SDF-1 with hemodynamic function and infarct size using cardiac MR in patients with AMI

Purpose: Platelet-derived stromal-cell-derived factor-1 (SDF-1) plays an important role in trafficking hematopoetic progenitor cells for tissue regeneration and neovascularisation. The aim was to evaluate platelet-SDF-1 and CD34(+) progenitor cells in patients with acute myocardial infarction (AMI) compared with hemodynamic function and infarct size using late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging. Materials and methods: We consecutively evaluated 40 patients with AMI, who received coronary angiography for primary coronary intervention. Blood was sampled for flow cytometry to determine mean fluorescence intensity (MFI) of platelet-SDF-1 and for isolation of CD34(+) progenitor cells. 48 h and three months after coronary stenting, all patients underwent 1.5 T CMR for volumetric assessment and LGE. Results: Patients with enhanced platelet-SDF-1 expression (median = 68.5 MFI) showed a significant amelioration of left ventricular ejection fraction (LVEF) (baseline vs. follow-up mean +/- SD: 45 +/- 6% vs. 56 +/- 6%; P = 0.018) and of stroke volume (73.1 +/- 19.1 mL vs. 89.9 +/- 21.3 mL; P = 0.032) at three-month follow-up in contrast to patients with a decreased platelet-SDF-1 expression level (LVEF: 53 +/- 8% vs. 56 +/- 10%; P = 0.267; stroke volume: 85.6 +/- 23.1 mL vs. 87.4 +/- 23.2 mL; P = 0.803). Inversely, LGE infarct size showed significantly reduced in patients with enhanced platelet-SDF-1 expression at three months (18.9 +/- 12 mL vs. 6.3 +/- 5.1 mL; P = 0.002) compared to patients with decreased platelet-SDF-1 (12.7 +/- 12.7 mL vs. 7.6 +/- 8.4 mL; P = 0.156). Time-dependent autocorrelation coefficients shifted for both SV (lag 1: r = -0.368; P = 0.001) and the number of CD34(+) cells (lag 1: r = 0.633; P = 0.001) to a positive autocorrelation (SV; lag 2: r = 0.295; P = 0.001; CD34(+) cells; lag 2: r = 0.287; P = 0.001). Patients with increased number of CD34(+) cells (median = 420 cells/hpf) showed a significant amelioration of stroke volume in three-month followup (83.9 +/- 5.3 mL vs. 99.4 +/- 4.1 mL; P = 0.020) compared with patients with decreased number of CD34(+) cells (69.3 +/- 4.1 mL vs. 76.1 +/- 3.2 mL; P = 0.282). Conclusions: Platelet-SDF-1 and number of CD34(+) progenitor cells are associated with CMR hemodynamic function in patients with AMI. (C) 2011 Elsevier Ireland Ltd. All rights reserved.