PercutaneOus StEm Cell Injection Delivery Effects On Neomyogenesis in Dilated CardioMyopathy (The POSEIDON-DCM Study)

The technique of transplanting progenitor cells into a region of damaged myocardium, termed cellular cardiomyoplasty1, is a potentially new therapeutic modality designed to replace or repair necrotic, scarred, or dysfunctional myocardium2-4. Ideally, graft cells should be readily available, easy to culture to ensure adequate quantities for transplantation, and able to survive in host myocardium; often a hostile environment of limited blood supply and immunorejection. Whether effective cellular regenerative strategies require that administered cells differentiate into adult cardiomyocytes and couple electromechanically with the surrounding myocardium is increasingly controversial and recent evidence suggests that this may not be required for effective cardiac repair. Most importantly, transplantation of graft cells should improve cardiac function and prevent adverse ventricular remodeling. To date, a number of candidate cells have been transplanted in experimental models, including fetal and neonatal cardiomyocytes5, embryonic stem cell-derived myocytes6, 7, tissue engineered contractile grafts8, skeletal myoblasts9, several cell types derived from adult bone marrow10-15, and cardiac precursors residing within the heart itself16. There has been substantial clinical development in the use of whole bone marrow and skeletal myoblast preparations in studies enrolling both post-infarction patients, and patients with chronic ischemic left ventricular dysfunction and heart failure. The effects of bone-marrow derived mesenchymal stem cells (MSCs) have also been studied clinically. Currently, bone marrow or bone marrow-derived cells represent highly promising modality for cardiac repair. The totality of evidence from trials investigating autologous whole bone marrow infusions into patients following myocardial infarction supports the safety of this approach. In terms of efficacy, increases in ejection fraction are reported in the majority of the trials. Non-ischemic dilated cardiomyopathy is a common and problematic condition; definitive therapy in the form of heart transplantation is available to only a tiny minority of eligible patients. Cellular cardiomyoplasty for chronic heart failure has been studied less than for acute MI, but represents a potentially important alternative for this disease.