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

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.

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. 48h and three months after coronary stenting, all patients underwent 1.5T CMR for volumetric assessment and LGE.

Patients with enhanced platelet-SDF-1 expression (median≥68.5MFI) 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±19.1mL vs. 89.9±21.3mL; 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±23.1mL vs. 87.4±23.2mL; P=0.803). Inversely, LGE infarct size showed significantly reduced in patients with enhanced platelet-SDF-1 expression at three months (18.9±12mL vs. 6.3±5.1mL; P=0.002) compared to patients with decreased platelet-SDF-1 (12.7±12.7mL vs. 7.6±8.4mL; 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≥420cells/hpf) showed a significant amelioration of stroke volume in three-month follow-up (83.9±5.3mL vs. 99.4±4.1mL; P=0.020) compared with patients with decreased number of CD34(+) cells (69.3±4.1mL vs. 76.1±3.2mL; P=0.282).

Platelet-SDF-1 and number of CD34(+) progenitor cells are associated with CMR hemodynamic function in patients with AMI.