The role of stem cells in the post-MI patient.

Studies suggest that cardiac transfer of stem and progenitor cells can have a favorable impact on tissue perfusion and contractile performance after acute myocardial infarction (AMI). Although the mechanistic background of stem cell therapy is still intensely debated, stem cell therapy has been introduced into the clinical setting, where the first randomized, controlled trials indicate that it is feasible and safe in patients. Preliminary efficacy data indicate that stem cells have the potential to enhance myocardial perfusion and/or contractile performance in patients with AMI. The field now is rapidly moving toward intermediate-size, double-blind trials to gather more safety and efficacy data and the first insights into clinical end points. Ultimately, large outcome trials will be needed. At the same time, continued basic research is needed to elucidate the underlying mechanism of stem cell therapy.