Abstract
Purpose: To assess the technical feasibility of percutaneous endoventricular injection of skeletal myoblasts into an infarcted porcine myocardium. Methods: A skeletal muscle biopsy was obtained from a donor pig and processed for myoblast expansion in vitro. Myocardial infarction was induced in a host pig via fibrin coil placement in the left anterior descending artery. Four weeks later, electromechanical mapping of the left ventricle identified the infarction site, into which ∼200 million allogenic cells obtained from the muscle biopsy were directly injected (0.1 mL/injection at 25 sites) from inside the ventricular cavity via a needle injection catheter inserted through the femoral artery. Ten days after transplantation, the injected heart was evaluated histologically for the presence of myoblasts. Results: Electrocardiography, echocardiography, left ventricular angiography, and electromechanical mapping confirmed the myocardial infarction. During the cell transfer procedure, premature ventricular contractions confirmed needle placement in the endocardium. Histological evaluation of the host heart 10 days after cell transfer revealed living myoblasts and multinucleated myotubes in the infarcted region, indicating successful transplantation. Conclusions: Direct myoblast transplantation into infarcted porcine myocardium using an endoventricular injection was technically feasible. The results in this model show that transplanted myoblasts were able to survive for 10 days after transplantation.