Percutaneous Approach to Achieve Therapeutic Myocardial Angiogenesis

Myocardial therapeutic angiogenesis is a novel approach for treating the large number of patients with advanced symptomatic coronary artery disease not amenable to conventional revascularization approaches. Proof of concept has been demonstrated in animal models of myocardial ischemia, and preliminary results suggest possible benefit in clinical trials of direct surgical (transepicardial) delivery of proteins and recombinant genes encoding angiogenic growth factors. Catheter-based intramyocardial gene delivery strategies have been tested in parallel, with the assumption that the less invasive nature and the potential for multiple treatment sessions would make this technique more applicable. Currently, most of the data relating to the catheter-based transendocardial delivery of angiogensis factors are derived from the experience with a single device (Biosense; Johnson & Johnson, Skillman, NJ). Using this injection platform, catheter-based gene delivery was demonstrated in animals to be safe and feasible, with a transfection yield similar to that achieved by the direct transepicardial approach. At the time of this review, more than 45 patients have been enrolled in Phase I clinical trials that evaluate the safety and feasibility of transendocardial delivery of adenovirus and plasmid-mediated gene transfection as well as cellular elements.