Patients with ICM who received MSCs via transendocardial stem cell injection ( TESI ) as part of the TAC-HFT ( Transendocardial Autologous Cells in Ischemic Heart Failure ) ( n = @ ) and POSEIDON ( Percutaneous Stem Cell Injection Delivery Effects on Neomyogenesis ) ( n = @ ) clinical trials were divided into @ age groups : younger than @ and @ years of age and older .