Stem cell transplantation includes a variety of cells which have been used for testing in clinical trials:

Skeletal muscle derived stem cells (myoblasts) are being explored as a potential new treatment for patients who are diagnosed with congestive heart failure. See myogenesis.

Bone marrow derived stem cells (Mesenchyma stem cells). The purpose of these cells is to potentially improve the inflammatory process after a heart attack and to potentially halt the progression toward heart failure. See below "preserving deterioration of heart function after a heart attack."

Peripheral blood derived stem cells (CD34). These cells are used for the formation of new blood vessels which may have the potential to increase the blood supply to improve refractory chest pain. These cells are being tested in patient who continue to have chest pain in spite of the standard treatment.

http://clinicaltrials.gov
www.centerwatch.com
http://en.wikipedia.org/wiki/Clinical_trial