Noninvasive methods for monitoring cardiac stem cell therapy

Myocardial infarction remains a major cause of death despite the continuous improvements in standard invasive and pharmacologic therapy. Cardiac regeneration by use of stem cells or progenitor cells has been proposed, and it has been carried into clinical trials based on initial success in experimental studies. However, recently reported results were inconsistent, and the clinical efficacy is still debated. Strategies to optimize cell delivery and engraftment are highly relevant for the future success of this therapeutic approach. Noninvasive imaging may play a key role in this optimization process. It has been used to monitor the efficacy of therapy through recovery of perfusion, metabolism, and functional parameters as essential surrogate end points of clinical outcome. Additionally, novel techniques for visualization and tracking of transplanted cells after therapeutic administration have been introduced. Ultimately, it is anticipated that existing and novel noninvasive imaging approaches will provide further insights into biology of cells, disease, and therapeutic mechanisms, and may thereby help to expedite the success of cell therapy.