Scientists at the University of California have found a new biomaterial that can heal damaged cardiac muscle tissue in animals from the inside out after a heart attack. It could soon be used in human trials they say. Normally, the cardiac muscle tissue is killed after a heart attack, leaving damaged scar tissue behind. But this new biomaterial made out of the extracellular matrix derived from body fat is thin enough to be delivered to the heart blood vessels intravenously. Made ouf ot nanoparticles, the material binds to leaky vessels and prevents inflammation whilst stimulating the healing process. Further studies are needed to begin human trials but the effects of cardiac tissue repair are promising. Then, the biomaterial could possibly be used for treatment of other leaky vessels in other hard-to-access organs such as the brain.