Tissue Engineering Strategies For Cardiac Regeneration

Once injured, cardiac muscle does not regenerate. Massive and irreversible loss of cardiomyocytes due to myocardial infarction remains the main cause of heart failure. Cardiac tissue engineering has a potential to reestablish the structure and function of injured myocardium, by (1) injection of cardiogenic cells, (2) transplantation of functional cardiac tissue constructs, or (3) mobilization of endogenous repair cells. Irrespective of the therapeutic strategy, the regeneration depends on both the biological potential of the repair cells and the environment (matrix, signals) to which the cells are subjected. In general, the biological potential of the cells the actual "tissue engineers" needs to be mobilized by providing highly controllable "biomimetic" environments designed to enhance cell survival, differentiation, and electromechanical coupling. For cardiac regeneration, some of the key requirements include the establishment of cardiac tissue matrix, electromechanical cell coupling, robust contractile function, and functional vascularization. Engineered tissue constructs can also serve as high-fidelity models to study cardiac development and disease. We review the potential and challenges of cardiac tissue engineering to provide for the development of therapies for heart regeneration.