Compositions and methods for treating heart disease

A method for treating a cardiac disease or disorder in a subject in need thereof, the method comprises administering between the pericardium layer and the epicardium layer of said subject a pharmaceutical composition comprising stem cells and/or progenitor cells embedded in a biodegradable thermoreversible hydrogel, wherein the hydrogel is characterized by a viscosity of less than 200 Pa's between 4° C. and 12° C., and a viscosity of more than 1,000 Pa's at 37° C., and/or wherein said hydrogel comprises ethylene oxide/propylene oxide block copolymer, hydroxypropylmethylcellulose (HPMC) and an adhesive agent.