RESUMO
BACKGROUND: The aim of this study was to investigate the effect of intracoronary administration of freshly isolated, uncultured autologous tissue-derived stromal cells on cardiac function and perfusion after acute infarction in pigs. METHODS: A transmural myocardial infarction in a porcine model was induced by occlusion of the mid LAD with an angioplasty balloon for 3 h. Upon reperfusion, freshly isolated, uncultured autologous stromal cells (1.5×106 cells/kg) or control solution was injected into the infarct artery. Cardiac function and area at risk were determined by (99m)Tc-SPECT. RESULTS: Eight weeks after infarction, cell treated pigs showed a 20% smaller myocardial perfusion defect compared to control animals (35±9% vs. 44±5% of LV, treated vs. control, respectively, p<0.05). The reduction of the perfusion defect was associated with a significantly higher myocardial salvage index in the cell group as well as a significant increase in ejection fraction compared to control (EF at 8 weeks 43±7% vs. 35±3%, treated vs. control, respectively, p<0.05). This functional improvement was reflected by an increased wall thickness of the infarct and border zone in the treated group (11.2±2.2 mm) compared to control (8.6±1.6 mm, p<0.05) as well as an increased capillary density in the border zone (treated vs. control; 41.6±17.9 vs. 32.9±12.6 capillaries per 0.1 mm², p<0.05). CONCLUSIONS: This study demonstrates for the first time that recovery and intracoronary delivery of uncultured autologous tissue derived stromal cells at time of vessel reperfusion is feasible and improves ventricular function.