Percutaneous bone-marrow-derived cell transplantation:: clinical observations

Different types and routes of stem cell delivery have been used in clinical practice to repair infarcted or ischaemic myocardium. Of these, percutaneous administration of bone-marrow-derived progenitors represents the most optimal method to date, as it allows the evaluation of the cells' effects independent of revascularization and the application of multiple administrations over time. Two different percutaneous catheter-based methods have been used in clinical trials to deliver bone-marrow-derived stem cells: intracoronary infusion and transendomyocardial delivery through a left ventricle catheter. Despite the clinical scenarios investigated (acute myocardial infarction, chronic ischaemia with no revascularization option, and ischaemic cardiomyopathy), in general percutaneous bone-marrow-derived stem cell therapy is feasible, relatively safe (with unresolved concerns regarding arrhythmias, restenosis, and atherosclerosis progresion), and could exert a benefit upon ventricular function and perfusion. At this point, intermediate-size, randomized trials are aimed to well establish the efficacy of this therapy that analyses surrogate endpoints: either perfusion or left ventricular function based on the clinical scenario tested.