An in vitro method of producing stem cells with potential to develop into cardiovascular myocytes is disclosed which comprises culturing myogenic stem cells obtained from the stromal or mesenchymal compartment of adult adipose tissue in a medium that favors myogenic development of the cells. These myogenic stem cells highly express telomerase and myocardin. A composition comprising fat-derived myogenic stem cells and/or differentiated cardiovascular myocytes and a method for treating a mammalian subject suffering from a cardiovascular disorder are also disclosed.