Gene Delivery to Organs

Application of a virus with poloxamer alone onto atria results in diffuse epicardial gene transfer with negligible penetration into the myocardium. Progressive increases in protease concentration, however, allow transmural gene transfer. After protease exposure, echocardiographic left atrial diameter does not change. Left atrial ejection fraction decreases on post-operative day 3, but returns to baseline by day 7. At appropriate protease concentrations, tissue tensile strength is unaffected by the procedure. Transmural atrial gene transfer can be effected using this direct "painting" method.