The present invention relates to improved therapies for the treatment of heart disease, particularly the improved delivery of therapeutic agents to heart tissue by direct infusion into the coronary circulation. A preferred embodiment of the invention is a method comprising, identifying a mammal in need of treatment or prevention of heart disease, and supplying NO to the coronary circulation prior to, and/or during the infusion of a therapeutic polynucleotide into a blood vessel of the coronary circulation in vivo.
