Cardiac Regeneration After Myocardial Infarction: an Approachable Goal

PURPOSE OF REVIEW: Until recently, cardiac regeneration after myocardial infarction has remained a holy grail in cardiology. Failure of clinical trials using adult stem cells and scepticism about the actual existence of such cells has reinforced the notion that the heart is an irreversibly post-mitotic organ. Recent evidence has drastically challenged this conclusion. RECENT FINDINGS: Cardiac regeneration can successfully be obtained by at least two strategies. First, new cardiomyocytes can be generated from embryonic stem cells or induced pluripotent stem cells and administered to the heart either as cell suspensions or upon ex vivo generation of contractile myocardial tissue. Alternatively, the endogenous capacity of cardiomyocytes to proliferate can be stimulated by the delivery of individual genes or, more successfully, of selected microRNAs. SUMMARY: Recent experimental success in large animals by both strategies now fuels the notion that cardiac regeneration is indeed possible. Several technical hurdles, however, still need to be addressed and solved before broad and successful clinical application is achieved.