Cardiac pacing: from biological to electronic ... to biological?

The prevention and treatment of life-threatening bradyarrhythmias have been revolutionized in the last half century by electronic pacemakers. Because this represents a palliative therapy, attempts have begun to effect a cure with the novel tools of gene and cell therapy. Over time, the strategies used have coalesced to focus on achieving a stable and autonomically responsive cardiac rhythm in a setting that ultimately would require no implanted hardware. In this report, we review the history of the disease process being treated, approaches now in progress, and the demands that must be met if biological therapies are to be successful.