Heart failure is a major health problem on a global scale. Current therapies 
include drug treatments, lifestyle modification, device therapy and heart 
transplantation. However, the "holy grail" of heart failure treatment would be 
to achieve widespread regeneration of diseased cardiac tissue. Examples of 
regeneration of living tissue are present in nature and involve stem cells. The 
two key defining properties of stem cells are their ability to renew themselves 
through cell division and to differentiate into various cell types. Generally, 
stem cells can be classified into embryonic or adult forms. Human adult stem 
cells are ethically appealing and have already been used in clinical trials in a 
variety of disease states. Bone marrow derived stem cells, skeletal myoblasts 
and resident adult cardiac stem cells are being explored as potential cell types 
for heart failure treatment. These cells can be delivered to the heart via a 
number of routes. Several clinical trials using adult stem cell have shown 
improvements in cardiac function, however, the mechanism of their action is 
unclear and widespread tissue regeneration is not evident. A more comprehensive 
understanding of regenerative physiology at the "benchside" combined with 
ongoing investigations at the bedside, will be paramount in achieving the 
ultimate goal of stem cell treatment-complete regeneration and repair of tissue.