Cell-based myocardial repair: how should we proceed?

Cell-based myocardial repair and regeneration heralds a new frontier in the treatment of cardiovascular disease. It provides an unprecedented opportunity to treat the underlying loss of cardiomyocytes that occurs after myocardial injury and that results in the cascade of events leading to heart failure. Yet, even as it progresses to the clinic, much remains to be understood about this technology. For example, controversies exist over the specific cells to be used, the cell dosages needed, how cells will impact the electrical activity of the myocardium, and even whether transplanted cells can actually improve myocardial function. We can perhaps answer these questions more quickly and more effectively - and thus benefit patients more rapidly - if we learn from the successes and failures of our gene therapy colleagues and take a prudent, step-wise approach from bench to bedside. To do so, we need only to promise what we can deliver, to do careful science, and then to deliver well on our promises. Although cellular cardiomyoplasty (cell transplantation for cardiac repair) shows great early clinical promise, its future as a new frontier in the treatment for cardiovascular disease will rest heavily on how we move forward in the next few years. Its success will heavily depend upon conducting carefully controlled, randomized double-blind clinical trials with appropriate endpoints, in the right patients. Choice of cell type, and mode of cell delivery, will also have to be considered, and may have to be matched to the patient. Irrespective of cell type, we can also be assured that cells offer both an opportunity for tissue repair and the potential for not yet understood outcomes. As with any frontier, there will be pitfalls and consequences to be considered that may surpass those of previous endeavors. But so too is the potential for previously unimagined success at treating the leading cause of death in the western world. In short, the promise for cardiovascular cell therapy is too great to be spoiled by ill-designed attempts that forget to account for both the natural propensities of cells and of the myocardium.