Cardiac Cell Therapy

Heart failure is frequently called the new epidemic of the 21st century, since the prevalence of this malignant disease has remained high through the last decade,1 mostly driven by the increased survival of patients with large acute myocardial infarctions. Established therapies aim at reducing preload, afterload, and neurohumoral activation, as well as mineralocorticoid dysregulation. However, the underlying ongoing loss of cardiomyocytes, which is followed by fibrosis, is only marginally influenced.Article, see p 1361 Cell therapy offers the attractive toolkit to improve cardiac function and to reduce adverse left ventricular remodeling.2 The scientific approach of using cell therapy generates new understandings for disease pathology, progression, and endogenous repair capacity. As part of a landmark investigation, the annual cardiomyocyte turnover-rate was estimated to be 1% in young adults, which decreases to 0.5% in the elderly, suggesting that approximately half of the heart’s muscle cells are renewed during lifespan.3 However, this endogenous repair capacity is not sufficient to cope with the loss of cardiomyocytes after acute myocardial infarction or other heart diseases. Enhancement of endogenous repair processes, optimally within a preconditioned microenvironment, would therefore offer unprecedented tools to enhance regenerative capacity and to modify adverse left ventricular remodeling.Indeed, supported by preclinical studies, numerous phase I and phase II clinical trials have been initiated and completed for more than 10 years now, testing various cell types and application protocols in a huge heterogeneity of patient conditions.4 However, clinical progress in developing convincing and successful therapies was rather modest, which can in part be attributed to rather small, underpowered trials using surrogate endpoints and open-label treatment approaches carrying the risk of bias.In an effort to overcome some of the mentioned limitations …