[Visualisation of early engraftment of transcoronary applied CD34+ cells in the infarct border zone].

Successful delivery of progenitor cells to the injury zone is a prerequisite for any effect of myocardial regeneration therapy. This key issue, however, has received far less attention than, for instance, a potential need for cell type selection or ex-vivo expansion, the optimal timing of cell application or multimodal functional evaluation after cellular transplantation. By combining myocardial perfusion scintigraphy, magnetic resonance imaging and 99Tc-HMPAO-labelled autologous bone marrow-derived CD34+ cells visualisation, we show in a 63-year-old man with a large anterior myocardial infarction that transcoronary applied cells (via the central lumen of an inflated over-the-wire balloon positioned in the stent implanted in primary PCI) graft preferentially to the infarct border zone. This is consistent with the idea that the area of myocardial 'irreversible' injury (i.e. the no-perfusion zone on perfusion scintigraphy or late enhancement zone on magnetic resonance) remains largely inaccessible to transcoronary-applied cells; thus other techniques need to be considered if the cell delivery is aimed at the zone of irreversible injury. The potency of such combined high-resolution visualisation provides grounds for comparing the efficacy of different methods of cell delivery after a recent myocardial infarction in man.